Quarterly report pursuant to Section 13 or 15(d)

Fair Value, Measurement Inputs, Disclosure (Details)

v3.19.1
Fair Value, Measurement Inputs, Disclosure (Details) - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Mar. 31, 2018
Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Debt Securities, Available-for-sale, Categorized as Level 2 Assets 99.40%      
Debt Securities, Available-for-sale, Categorized as Level 3 Assets 0.60%      
Assets Reported at Fair Value, Debt Securities, Available-for-sale 91.40%      
Mortgage Servicing Rights Categorized as Level 3 Assets 100.00%      
Over-the-Counter Derivatives Categorized as Level 2 Assets (Liabilities) 100.00%      
Other RMBS Classified as Derivatives Categorized as Level 2 Assets 100.00%      
Other Derivatives Categorized as Level 1 Assets (Liabilities) 100.00%      
Mortgage servicing rights $ 2,014,370 $ 1,993,440 $ 1,301,023 $ 1,086,717
Derivative assets, at fair value 336,112 319,981    
Derivative liabilities, at fair value 231 820,590    
Fair Value, Measurements, Recurring [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Available-for-sale securities 25,077,710 25,552,604    
Mortgage servicing rights 2,014,370 1,993,440    
Derivative assets, at fair value 336,112 319,981    
Total assets 27,428,192 27,866,025    
Derivative liabilities, at fair value 231 820,590    
Total liabilities 231 820,590    
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Available-for-sale securities 0 0    
Mortgage servicing rights 0 0    
Derivative assets, at fair value 63,925 21,602    
Total assets 63,925 21,602    
Derivative liabilities, at fair value 0 0    
Total liabilities 0 0    
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Available-for-sale securities 24,923,656 25,447,447    
Mortgage servicing rights 0 0    
Derivative assets, at fair value 272,187 298,379    
Total assets 25,195,843 25,745,826    
Derivative liabilities, at fair value 231 820,590    
Total liabilities 231 820,590    
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Available-for-sale securities 154,054 105,157    
Mortgage servicing rights 2,014,370 1,993,440    
Derivative assets, at fair value 0 0    
Total assets 2,168,424 2,098,597    
Derivative liabilities, at fair value 0 0    
Total liabilities $ 0 $ 0