Annual report pursuant to Section 13 and 15(d)

Fair Value

v3.8.0.1
Fair Value
12 Months Ended
Dec. 31, 2017
Fair Value Disclosures [Abstract]  
Fair Value
Fair Value
Fair Value Measurements
ASC 820 defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. ASC 820 clarifies that fair value should be based on the assumptions market participants would use when pricing an asset or liability and establishes a fair value hierarchy that prioritizes the information used to develop those assumptions. The fair value hierarchy gives the highest priority to quoted prices available in active markets (i.e., observable inputs) and the lowest priority to data lacking transparency (i.e., unobservable inputs). Additionally, ASC 820 requires an entity to consider all aspects of nonperformance risk, including the entity’s own credit standing, when measuring fair value of a liability.
ASC 820 establishes a three-level hierarchy to be used when measuring and disclosing fair value. An instrument’s categorization within the fair value hierarchy is based on the lowest level of significant input to its valuation. Following is a description of the three levels:

Level 1
Inputs are quoted prices in active markets for identical assets or liabilities as of the measurement date under current market conditions. Additionally, the entity must have the ability to access the active market and the quoted prices cannot be adjusted by the entity.
Level 2
Inputs include quoted prices in active markets for similar assets or liabilities; quoted prices in inactive markets for identical or similar assets or liabilities; or inputs that are observable or can be corroborated by observable market data by correlation or other means for substantially the full-term of the assets or liabilities.
Level 3
Unobservable inputs are supported by little or no market activity. The unobservable inputs represent the assumptions that market participants would use to price the assets and liabilities, including risk. Generally, Level 3 assets and liabilities are valued using pricing models, discounted cash flow methodologies, or similar techniques that require significant judgment or estimation.

Following are descriptions of the valuation methodologies used to measure material assets and liabilities at fair value and details of the valuation models, key inputs to those models and significant assumptions utilized.
Available-for-sale securities. The Company holds a portfolio of AFS securities that are carried at fair value in the consolidated balance sheets and primarily comprised of Agency RMBS and non-Agency securities. The Company determines the fair value of its Agency RMBS based upon prices obtained from third-party pricing providers or broker quotes received using bid price, which are deemed indicative of market activity. The third-party pricing providers and brokers use pricing models that generally incorporate such factors as coupons, primary and secondary mortgage rates, rate reset period, issuer, prepayment speeds, credit enhancements and expected life of the security. In determining the fair value of its non-Agency securities, management judgment may be used to arrive at fair value that considers prices obtained from third-party pricing providers, broker quotes received and other applicable market data. If observable market prices are not available or insufficient to determine fair value due principally to illiquidity in the marketplace, then fair value is based upon internally developed models that are primarily based on observable market-based inputs but also include unobservable market data inputs (including prepayment speeds, delinquency levels, and credit losses). The Company classified 99.3% and 0.7% of its AFS securities as Level 2 and Level 3 fair value assets, respectively, at December 31, 2017. AFS securities account for 93.6% of all assets reported at fair value at December 31, 2017.
Mortgage servicing rights. The Company holds a portfolio of MSR that are carried at fair value on the consolidated balance sheets. The Company determines fair value of its MSR based on prices obtained from third-party pricing providers. Although MSR transactions are observable in the marketplace, the valuation is based upon cash flow models that include unobservable market data inputs (including prepayment speeds, delinquency levels and discount rates). As a result, the Company classified 100% of its MSR as Level 3 fair value assets at December 31, 2017.
Residential mortgage loans held-for-investment in securitization trusts. Prior to December 31, 2017, the Company recognized on its consolidated balance sheets residential mortgage loans held-for-investment in securitization trusts that were carried at fair value as a result of a fair value option election. An entity is allowed to measure both the financial assets and financial liabilities of a qualifying collateralized financing entity, or CFE, it consolidates using the fair value of either the CFE’s financial assets or financial liabilities, whichever is more observable. As the Company’s securitization trusts were considered qualifying CFEs, the Company determined the fair value of these residential mortgage loans based on the fair value of its collateralized borrowings in securitization trusts and its retained interests from the Company’s on-balance sheet securitizations (eliminated in consolidation in accordance with U.S. GAAP), as the fair value of these instruments is more observable. Prior to December 31, 2017, the Company classified its residential mortgage loans held-for-investment in securitization trusts as Level 2 fair value assets. As of December 31, 2017, the Company no longer consolidates the trusts and includes the remaining retained securities within non-Agency AFS securities.
Residential mortgage loans held-for-sale. The Company holds residential mortgage loans held-for-sale that are carried at fair value in the consolidated balance sheets as a result of a fair value option election. The Company determines fair value of its residential mortgage loans based on prices obtained from third-party pricing providers and other applicable market data. If observable market prices are not available or insufficient to determine fair value due principally to illiquidity in the marketplace, then fair value is based upon cash flow models that are primarily based on observable market-based inputs but also include unobservable market data inputs (including prepayment speeds, delinquency levels and credit losses). The Company classified 1.6% and 98.4% of its residential mortgage loans held-for-sale as Level 2 and Level 3 fair value assets, respectively, at December 31, 2017.
Derivative instruments. The Company may enter into a variety of derivative financial instruments as part of its hedging strategies. The Company principally executes over-the-counter, or OTC, derivative contracts, such as interest rate swaps, swaptions, put and call options for TBAs and Markit IOS total return swaps. The Company utilizes third-party pricing providers to value its financial derivative instruments. The Company classified 100% of the interest rate swaps, swaptions, put and call options for TBAs and Markit IOS total returns swaps reported at fair value as Level 2 at December 31, 2017.
The Company may also enter into certain other derivative financial instruments, such as TBAs, short U.S. Treasuries and inverse interest-only securities. These instruments are similar in form to the Company’s AFS securities and the Company utilizes a pricing service to value TBAs and broker quotes to value short U.S. Treasuries and inverse interest-only securities. The Company classified 100% of its inverse interest-only securities at fair value as Level 2 at December 31, 2017. The Company reported 100% of its TBAs as Level 1 as of December 31, 2017. The Company did not hold any short U.S. Treasuries at December 31, 2017.
The Company’s risk management committee governs trading activity relating to derivative instruments. The Company’s policy is to minimize credit exposure related to financial derivatives used for hedging by limiting the hedge counterparties to major banks, financial institutions, exchanges, and private investors who meet established capital and credit guidelines as well as by limiting the amount of exposure to any individual counterparty.
The Company has netting arrangements in place with all derivative counterparties pursuant to standard documentation developed by ISDA, or central clearing exchange agreements, in the case of centrally cleared interest rate swaps. Additionally, both the Company and the counterparty or clearing agency are required to post cash collateral based upon the net underlying market value of the Company’s open positions with the counterparty. Posting of cash collateral typically occurs daily, subject to certain dollar thresholds. Due to the existence of netting arrangements, as well as frequent cash collateral posting at low posting thresholds, credit exposure to the Company and/or to the counterparty or clearing agency is considered materially mitigated. Based on the Company’s assessment, there is no requirement for any additional adjustment to derivative valuations specifically for credit.
Equity securities. The Company’s equity securities are carried at fair value and reported in other assets on the consolidated balance sheets. Changes in fair value are recorded as a component of (loss) gain on investment securities in the consolidated statements of comprehensive income (loss). The Company determines fair value of its equity securities based on the closing market price of the securities at period end.
Collateralized borrowings in securitization trusts. Prior to December 31, 2017 the Company recognized on its consolidated balance sheets collateralized borrowings in securitization trusts that were carried at fair value as a result of a fair value option election. In determining the fair value of its collateralized borrowings, management judgment was used to arrive at fair value that considers prices obtained from third-party pricing providers, broker quotes received and other applicable market data. If observable market prices were not available or insufficient to determine fair value due principally to illiquidity in the marketplace, then fair value was based upon internally developed models that were primarily based on observable market-based inputs but also included unobservable market data inputs (including prepayment speeds, delinquency levels, and credit losses). Prior to December 31, 2017, the Company classified its collateralized borrowings in securitization trusts as Level 2 fair value liabilities. As of December 31, 2017, the Company no longer consolidates the trusts and includes the remaining retained securities within non-Agency AFS securities.
The following tables display the Company’s assets and liabilities measured at fair value on a recurring basis. The Company often economically hedges the fair value change of its assets or liabilities with derivatives and other financial instruments. The tables below display the hedges separately from the hedged items, and therefore do not directly display the impact of the Company’s risk management activities.
 
Recurring Fair Value Measurements
 
December 31, 2017
(in thousands)
Level 1
 
Level 2
 
Level 3
 
Total
Assets
 
 
 
 
 
 
 
Available-for-sale securities
$

 
$
21,067,678

 
$
153,141

 
$
21,220,819

Mortgage servicing rights

 

 
1,086,717

 
1,086,717

Residential mortgage loans held-for-sale

 
474

 
29,940

 
30,414

Derivative assets
913

 
309,005

 

 
309,918

Equity securities
29,413

 

 

 
29,413

Total assets
$
30,326

 
$
21,377,157

 
$
1,269,798

 
$
22,677,281

Liabilities
 
 
 
 
 
 
 
Derivative liabilities
$
1,930

 
$
29,973

 
$

 
$
31,903

Total liabilities
$
1,930

 
$
29,973

 
$

 
$
31,903

 
Recurring Fair Value Measurements
 
December 31, 2016
(in thousands)
Level 1
 
Level 2
 
Level 3
 
Total
Assets
 
 
 
 
 
 
 
Available-for-sale securities
$

 
$
13,116,171

 
$

 
$
13,116,171

Mortgage servicing rights

 

 
693,815

 
693,815

Residential mortgage loans held-for-investment in securitization trusts

 
3,271,317

 

 
3,271,317

Residential mortgage loans held-for-sale

 
925

 
39,221

 
40,146

Derivative assets
4,294

 
319,888

 

 
324,182

Total assets
$
4,294

 
$
16,708,301

 
$
733,036

 
$
17,445,631

Liabilities
 
 
 
 
 
 
 
Collateralized borrowings in securitization trusts
$

 
$
3,037,196

 
$

 
$
3,037,196

Derivative liabilities
10,344

 
2,157

 

 
12,501

Total liabilities
$
10,344

 
$
3,039,353

 
$

 
$
3,049,697



The Company may be required to measure certain assets or liabilities at fair value from time to time. These periodic fair value measures typically result from application of certain impairment measures under U.S. GAAP. These items would constitute nonrecurring fair value measures under ASC 820. As of December 31, 2017, the Company did not have any assets or liabilities measured at fair value on a nonrecurring basis in the periods presented. 
The valuation of Level 3 instruments requires significant judgment by the third-party pricing providers and/or management. The third-party pricing providers and/or management rely on inputs such as market price quotations from market makers (either market or indicative levels), original transaction price, recent transactions in the same or similar instruments, and changes in financial ratios or cash flows to determine fair value. Level 3 instruments may also be discounted to reflect illiquidity and/or non-transferability, with the amount of such discount estimated by the third-party pricing provider in the absence of market information. Assumptions used by the third-party pricing provider due to lack of observable inputs may significantly impact the resulting fair value and therefore the Company’s consolidated financial statements. The Company’s valuation committee reviews all valuations that are based on pricing information received from a third-party pricing provider. As part of this review, prices are compared against other pricing or input data points in the marketplace, along with internal valuation expertise, to ensure the pricing is reasonable. In addition, the Company performs back-testing of pricing information to validate price information and identify any pricing trends of a third-party price provider.
In determining fair value, third-party pricing providers use various valuation approaches, including market and income approaches. Inputs that are used in determining fair value of an instrument may include pricing information, credit data, volatility statistics, and other factors. In addition, inputs can be either observable or unobservable.
The availability of observable inputs can vary by instrument and is affected by a wide variety of factors, including the type of instrument, whether the instrument is new and not yet established in the marketplace and other characteristics particular to the instrument. The third-party pricing provider uses prices and inputs that are current as of the measurement date, including during periods of market dislocations. In periods of market dislocation, the availability of prices and inputs may be reduced for many instruments. This condition could cause an instrument to be reclassified to or from various levels within the fair value hierarchy.
Securities for which market quotations are readily available are valued at the bid price (in the case of long positions) or the ask price (in the case of short positions) at the close of trading on the date as of which value is determined. Exchange-traded securities for which no bid or ask price is available are valued at the last traded price. OTC derivative contracts, including interest rate swaps and swaption agreements, put and call options for TBAs and U.S. Treasuries, constant maturity swaps, credit default swaps and Markit IOS total return swaps, are valued by the Company using observable inputs, specifically quotations received from third-party pricing providers, and are therefore classified within Level 2.
The following tables present the reconciliation for all of the Company’s Level 3 assets measured at fair value on a recurring basis:
 
Year Ended
 
 
December 31, 2017
 
(in thousands)
Available-For-Sale Securities
 
Mortgage Servicing Rights
 
Residential Mortgage Loans Held-For-Sale
 
Beginning of period level 3 fair value
$

 
$
693,815

 
$
39,221

 
Gains (losses) included in net income:
 
 
 
 
 
 
Realized (losses) gains

 
(97,372
)
 
1,780

 
Unrealized (losses) gains

 
6,339

(1) 
726

(3) 
Total gains (losses) included in net income

 
(91,033
)
 
2,506

 
Other comprehensive income (loss)
141

 

 

 
Purchases
153,000

 
499,886

 
575

 
Sales

 
(355
)
 
(3,717
)
 
Settlements

 
(15,596
)
 
(8,645
)
 
Gross transfers into level 3

 

 

 
Gross transfers out of level 3

 

 

 
End of period level 3 fair value
$
153,141

 
$
1,086,717

 
$
29,940

 
Change in unrealized gains or losses for the period included in earnings for assets held at the end of the reporting period
$
141

 
$
5,870

(2) 
$
916

(4) 
 
Year Ended
 
 
December 31, 2016
 
(in thousands)
Available-For-Sale Securities
 
Mortgage Servicing Rights
 
Residential Mortgage Loans Held-For-Sale
 
Beginning of period level 3 fair value
$

 
$
493,688

 
$
47,112

 
Gains (losses) included in net income:
 
 
 
 
 
 
Realized (losses) gains

 
(100,103
)
 
4,451

 
Unrealized (losses) gains

 
16,572

(1) 
(135
)
(3) 
Total gains (losses) included in net income

 
(83,531
)
 
4,316

 
Other comprehensive income (loss)

 

 

 
Purchases

 
313,504

 
183,074

 
Sales

 
(40,137
)
 
(98,338
)
 
Settlements

 
10,291

 
(96,943
)
 
Gross transfers into level 3

 

 

 
Gross transfers out of level 3

 

 

 
End of period level 3 fair value
$

 
$
693,815

 
$
39,221

 
Change in unrealized gains or losses for the period included in earnings for assets held at the end of the reporting period
$

 
$
13,906

(2) 
$
168

(4) 
___________________
(1)
The change in unrealized gains or losses on MSR was recorded in loss on servicing asset on the consolidated statements of comprehensive income (loss).
(2)
The change in unrealized gains or losses on MSR that were held at the end of the reporting period was recorded in loss on servicing asset on the consolidated statements of comprehensive income (loss).
(3)
The change in unrealized gains or losses on residential mortgage loans held-for-sale was recorded in gain on residential mortgage loans held-for-sale on the consolidated statements of comprehensive income (loss).
(4)
The change in unrealized gains or losses on residential mortgage loans held-for-sale that were held at the end of the reporting period was recorded in gain on residential mortgage loans held-for-sale on the consolidated statements of comprehensive income (loss).

The Company did not incur transfers between Level 1, Level 2 or Level 3 during the years ended December 31, 2017 and 2016. Transfers between Levels are deemed to take place on the first day of the reporting period in which the transfer has taken place.
The Company used broker quotes in the fair value measurement of its Level 3 available-for-sale securities. The significant unobservable inputs used by the broker included expected default, severity and discount rate. Significant increases (decreases) in any of the inputs in isolation may result in significantly lower (higher) fair value measurement.
The Company also used a third-party pricing provider in the fair value measurement of its Level 3 MSR. The table below presents information about the significant unobservable inputs used by the third-party pricing providers in the fair value measurement of the Company’s MSR classified as Level 3 fair value assets at December 31, 2017:
December 31, 2017
Valuation Technique
 
Unobservable Input (1)
 
Range
 
Weighted Average
Discounted cash flow
 
Constant prepayment speed
 
8.2
-
11.2
%
 
9.8%
 
 
Delinquency
 
1.3
-
2.0
%
 
1.7%
 
 
Discount rate
 
8.3
-
11.2
%
 
9.9%
December 31, 2016
Valuation Technique
 
Unobservable Input (1)
 
Range
 
Weighted Average
Discounted cash flow
 
Constant prepayment speed
 
8.0
-
10.3
%
 
9.2%
 
 
Delinquency
 
1.8
-
2.1
%
 
1.9%
 
 
Discount rate
 
8.4
-
10.2
%
 
9.4%
___________________
(1)
Significant increases (decreases) in any of the inputs in isolation may result in significantly lower (higher) fair value measurement. A change in the assumption used for discount rates may be accompanied by a directionally similar change in the assumption used for the probability of delinquency and a directionally opposite change in the assumption used for prepayment rates.

The Company used a third-party pricing provider in the fair value measurement of its Level 3 residential mortgage loans held-for-sale. The significant unobservable inputs used by the third-party pricing provider included expected default, severity and discount rate. Significant increases (decreases) in any of the inputs in isolation may result in significantly lower (higher) fair value measurement.
Fair Value Option for Financial Assets and Financial Liabilities
On July 1, 2015, the Company elected the fair value option for Agency interest-only securities and GSE credit risk transfer securities acquired on or after such date. The fair value option was elected to simplify the reporting of changes in fair value. Agency interest-only securities and GSE credit risk transfer securities are carried within AFS securities on the consolidated balance sheets. The Company’s policy is to separately record interest income, net of premium amortization or including discount accretion, on these fair value elected securities. Fair value adjustments are reported in (loss) gain on investment securities on the consolidated statements of comprehensive income (loss).
Prior to December 31, 2017 the Company elected the fair value option for both the residential mortgage loans held-for-investment in securitization trusts and the collateralized borrowings in securitization trusts that were carried on the consolidated balance sheets. The fair value option was elected to better reflect the economics of the Company’s retained interests. The Company’s policy was to separately record interest income on the fair value elected loans and interest expense on the fair value elected borrowings. Upfront fees and costs were not deferred or capitalized. Fair value adjustments are reported in other income (loss) on the consolidated statements of comprehensive income (loss). During the fourth quarter of 2017, the Company sold all of these retained subordinated securities thereby causing the deconsolidation of the securitization trusts from the Company’s consolidated balance sheet. As of December 31, 2017, the remaining retained securities were included within non-Agency AFS securities.
The Company also elected the fair value option for its residential mortgage loans held-for-sale. The fair value option was elected to mitigate earnings volatility by better matching the accounting for the assets with the related hedges. The mortgage loans are carried within residential mortgage loans held-for-sale on the consolidated balance sheets. The Company’s policy is to separately record interest income on these fair value elected loans. Upfront fees and costs related to the fair value elected loans are not deferred or capitalized. Fair value adjustments are reported in gain on residential mortgage loans held-for-sale on the consolidated statements of comprehensive income (loss).
The following tables summarize the fair value option elections and information regarding the line items and amounts recognized in the consolidated statements of comprehensive income (loss) for each fair value option-elected item.
 
Year Ended December 31, 2017
(in thousands)
Interest income (expense)
 
(Loss) gain on investment securities
 
Gain on residential mortgage loans held-for-sale
 
Other income (loss)
 
Total included in net income
 
Change in fair value due to credit risk
Assets
 
 
 
 
 
 
 
 
 
 
 
 
 
Available-for-sale securities
$
(4,062
)
 
 
$
3,915

 
$

 
$

 
$
(147
)
 
N/A

 
Residential mortgage loans held-for-investment in securitization trusts
102,886

(1) 
 

 

 
45,275

 
148,161

 
$

(2) 
Residential mortgage loans held-for-sale
1,704

(1) 
 

 
2,383

 

 
4,087

 
$
(1,120
)
(3) 
Liabilities
 
 
 
 
 
 
 
 
 
 
 
 
 
Collateralized borrowings in securitization trusts
(82,573
)
 
 

 

 
(22,592
)
 
(105,165
)
 

(2) 
Total
$
17,955

 
 
$
3,915

 
$
2,383

 
$
22,683

 
$
46,936

 
$
(1,120
)
 
 
Year Ended December 31, 2016
(in thousands)
Interest income (expense)
 
(Loss) gain on investment securities
 
Gain on residential mortgage loans held-for-sale
 
Other income (loss)
 
Total included in net income
 
Change in fair value due to credit risk
Assets
 
 
 
 
 
 
 
 
 
 
 
 
 
Available-for-sale securities
$
(281
)
 
 
$
1,905

 
$

 
$

 
$
1,624

 
N/A

 
Residential mortgage loans held-for-investment in securitization trusts
133,993

(1) 
 

 

 
(19,741
)
 
114,252

 
$

(2) 
Residential mortgage loans held-for-sale
23,037

(1) 
 

 
15,735

 

 
38,772

 
228

(3) 
Liabilities
 
 
 
 
 
 
 
 
 
 
 
 
 
Collateralized borrowings in securitization trusts
(97,729
)
 
 

 

 
7,907

 
(89,822
)
 

(2) 
Total
$
59,020

 
 
$
1,905

 
$
15,735

 
$
(11,834
)
 
$
64,826

 
$
228

 
 
Year Ended December 31, 2015
(in thousands)
Interest income (expense)
 
(Loss) gain on investment securities
 
Gain on residential mortgage loans held-for-sale
 
Other income (loss)
 
Total included in net income
 
Change in fair value due to credit risk
Assets
 
 
 
 
 
 
 
 
 
 
 
 
 
Available-for-sale securities
$
124

 
 
$
(68
)
 
$

 
$

 
$
56

 
N/A

 
Residential mortgage loans held-for-investment in securitization trusts
95,740

(1) 
 

 

 
(52,440
)
 
43,300

 

(2) 
Residential mortgage loans held-for-sale
28,966

(1) 
 

 
15,932

 

 
44,898

 
(6,365
)
(3) 
Liabilities
 
 
 
 
 
 
 
 
 
 
 
 
 
Collateralized borrowings in securitization trusts
(57,216
)
 
 

 

 
25,914

 
(31,302
)
 

(2) 
Total
$
67,614

 
 
$
(68
)
 
$
15,932

 
$
(26,526
)
 
$
56,952

 
$
(6,365
)
 
____________________
(1)
Interest income on residential mortgage loans held-for-sale and residential mortgage loans held-for-investment in securitization trusts is measured by multiplying the unpaid principal balance on the loans by the coupon rate and the number of days of interest due.
(2)
The change in fair value on residential mortgage loans held-for-investment in securitization trusts and collateralized borrowings in securitization trusts was due entirely to changes in market interest rates.
(3)
The change in fair value due to credit risk on residential mortgage loans held-for-sale was quantified by holding yield constant in the cash flow model in order to isolate credit risk component.

The table below provides the fair value and the unpaid principal balance for the Company’s fair value option-elected loans and collateralized borrowings.
 
December 31, 2017
 
December 31, 2016
(in thousands)
Unpaid Principal Balance
 
Fair
Value (1)
 
Unpaid Principal Balance
 
Fair
Value (1)
Residential mortgage loans held-for-investment in securitization trusts
 
 
 
 
 
 
 
Total loans
$

 
$

 
$
3,234,044

 
$
3,271,317

Nonaccrual loans
$

 
$

 
$
2,373

 
$
2,408

Loans 90+ days past due
$

 
$

 
$
1,401

 
$
1,419

Residential mortgage loans held-for-sale
 
 
 
 
 
 
 
Total loans
$
37,632

 
$
30,414

 
$
49,986

 
$
40,146

Nonaccrual loans
$
13,511

 
$
10,963

 
$
25,445

 
$
21,162

Loans 90+ days past due
$
12,136

 
$
9,857

 
$
21,759

 
$
18,203

Collateralized borrowings in securitization trusts
 
 
 
 
 
 
 
Total borrowings
$

 
$

 
$
3,015,162

 
$
3,037,196

____________________
(1)
Excludes accrued interest receivable.

Fair Value of Financial Instruments
In accordance with ASC 820, the Company is required to disclose the fair value of financial instruments, both assets and liabilities recognized and not recognized in the consolidated balance sheets, for which fair value can be estimated.
The following describes the Company’s methods for estimating the fair value for financial instruments. Descriptions are not provided for those items that have zero balances as of the current balance sheet date.
AFS securities, residential mortgage loans held-for-sale, residential mortgage loans held-for-investment in securitization trusts, MSR, derivative assets and liabilities, equity securities and collateralized borrowings in securitization trusts are recurring fair value measurements; carrying value equals fair value. See discussion of valuation methods and assumptions within the Fair Value Measurements section of this Note 14.
Cash and cash equivalents and restricted cash have a carrying value which approximates fair value because of the short maturities of these instruments. The Company categorizes the fair value measurement of these assets as Level 1.
As a condition to membership in the FHLB, the Company is required to purchase and hold a certain amount of FHLB stock, which is considered a non-marketable, long-term investment, and is carried at cost. Because this stock can only be redeemed or sold at its par value, and only to the FHLB, carrying value, or cost, approximates fair value. The Company categorizes the fair value measurement of these assets as Level 3.
Equity investments include cost method investments for which fair value is not estimated. Carrying value, or cost, approximates fair value. The Company categorizes the fair value measurement of these assets as Level 3.
The carrying value of repurchase agreements, FHLB advances and revolving credit facilities that mature in less than one year generally approximates fair value due to the short maturities. As of December 31, 2017, the Company held $112.5 million of repurchase agreements and $1.2 billion of FHLB advances that are considered long-term. The Company’s long-term repurchase agreements and FHLB advances have floating rates based on an index plus a spread and, for members of the FHLB, the credit spread is typically consistent with those demanded in the market. Accordingly, the interest rates on these borrowings are at market and thus carrying value approximates fair value. The Company categorizes the fair value measurement of these liabilities as Level 2.
Convertible senior notes are carried at their unpaid principal balance, net of any unamortized deferred issuance costs. The Company estimates the fair value of its convertible senior notes using the market transaction price on December 31, 2017. The Company categorizes the fair value measurement of these assets as Level 2.
The following table presents the carrying values and estimated fair values of assets and liabilities that are required to be recorded or disclosed at fair value at December 31, 2017 and December 31, 2016.
 
December 31, 2017
 
December 31, 2016
(in thousands)
Carrying Value
 
Fair Value
 
Carrying Value
 
Fair Value
Assets
 
 
 
 
 
 
 
Available-for-sale securities
$
21,220,819

 
$
21,220,819

 
$
13,116,171

 
$
13,116,171

Mortgage servicing rights
$
1,086,717

 
$
1,086,717

 
$
693,815

 
$
693,815

Residential mortgage loans held-for-investment in securitization trusts
$

 
$

 
$
3,271,317

 
$
3,271,317

Residential mortgage loans held-for-sale
$
30,414

 
$
30,414

 
$
40,146

 
$
40,146

Cash and cash equivalents
$
419,159

 
$
419,159

 
$
350,864

 
$
350,864

Restricted cash
$
635,836

 
$
635,836

 
$
408,052

 
$
408,052

Derivative assets
$
309,918

 
$
309,918

 
$
324,182

 
$
324,182

Equity securities
$
29,413

 
$
29,413

 
$

 
$

Federal Home Loan Bank stock
$
53,826

 
$
53,826

 
$
167,856

 
$
167,856

Equity investments
$
3,000

 
$
3,000

 
$
3,000

 
$
3,000

Liabilities
 
 
 
 
 
 
 
Repurchase agreements
$
19,451,207

 
$
19,451,207

 
$
8,865,184

 
$
8,865,184

Collateralized borrowings in securitization trusts
$

 
$

 
$
3,037,196

 
$
3,037,196

Federal Home Loan Bank advances
$
1,215,024

 
$
1,215,024

 
$
4,000,000

 
$
4,000,000

Revolving credit facilities
$
20,000

 
$
20,000

 
$
70,000

 
$
70,000

Convertible senior notes
$
282,827

 
$
306,351

 
$

 
$

Derivative liabilities
$
31,903

 
$
31,903

 
$
12,501

 
$
12,501