Quarterly report pursuant to Section 13 or 15(d)

Schedule of Available-for-sale Securities Reconciliation (Details)

v3.19.1
Schedule of Available-for-sale Securities Reconciliation (Details) - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]    
Principal/Current Face $ 33,370,489 $ 34,389,050
Unamortized Premium 1,224,233 1,338,210
Accretable Purchase Discount 575,214 719,204
Credit Reserve Purchase Discount 1,393,735 1,322,762
Amortized Cost 24,602,916 25,432,158
Unrealized Gain 656,479 557,048
Unrealized Loss 181,685 436,602
Available-for-sale securities, at fair value 25,077,710 25,552,604
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Principal/Current Face 23,341,406 23,891,757
Unamortized Premium 1,135,043 1,247,682
Accretable Purchase Discount 29 25,085
Credit Reserve Purchase Discount 0 0
Amortized Cost 21,465,085 21,998,387
Unrealized Gain 219,596 75,298
Unrealized Loss 151,483 388,652
Available-for-sale securities, at fair value 21,533,198 21,685,033
Mortgage-backed Securities, Issued by Private Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Principal/Current Face 10,029,083 10,497,293
Unamortized Premium 89,190 90,528
Accretable Purchase Discount 575,185 694,119
Credit Reserve Purchase Discount 1,393,735 1,322,762
Amortized Cost 3,137,831 3,433,771
Unrealized Gain 436,883 481,750
Unrealized Loss 30,202 47,950
Available-for-sale securities, at fair value 3,544,512 3,867,571
Interest-Only-Strip [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Principal/Current Face 3,011,335 3,115,967
Unamortized Premium 201,152 209,901
Accretable Purchase Discount 0 0
Credit Reserve Purchase Discount 0 0
Amortized Cost 201,152 209,901
Unrealized Gain 13,745 14,170
Unrealized Loss 47,887 48,655
Available-for-sale securities, at fair value 167,010 175,416
Interest-Only-Strip [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Principal/Current Face 5,011,522 5,137,169
Unamortized Premium 83,466 83,846
Accretable Purchase Discount 0 0
Credit Reserve Purchase Discount 0 0
Amortized Cost 83,466 83,846
Unrealized Gain 2,714 3,655
Unrealized Loss 3,247 3,293
Available-for-sale securities, at fair value 82,933 84,208
Fixed Income Securities [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Principal/Current Face 20,330,071 20,775,790
Unamortized Premium 933,891 1,037,781
Accretable Purchase Discount 29 25,085
Credit Reserve Purchase Discount 0 0
Amortized Cost 21,263,933 21,788,486
Unrealized Gain 205,851 61,128
Unrealized Loss 103,596 339,997
Available-for-sale securities, at fair value 21,366,188 21,509,617
Fixed Income Securities [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]    
Debt Securities, Available-for-sale [Line Items]    
Principal/Current Face 5,017,561 5,360,124
Unamortized Premium 5,724 6,682
Accretable Purchase Discount 575,185 694,119
Credit Reserve Purchase Discount 1,393,735 1,322,762
Amortized Cost 3,054,365 3,349,925
Unrealized Gain 434,169 478,095
Unrealized Loss 26,955 44,657
Available-for-sale securities, at fair value $ 3,461,579 $ 3,783,363