Annual report pursuant to Section 13 and 15(d)

Fair Value, Measurement Inputs, Disclosure (Details)

v3.20.4
Fair Value, Measurement Inputs, Disclosure (Details) - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Dec. 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 99.90%      
Debt Securities, Available-for-sale, Categorized as Level 3 Assets 0.10%      
Assets Reported at Fair Value, Debt Securities, Available-for-sale 89.60%      
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 $ 1,596,153 $ 1,909,444 $ 1,993,440 $ 1,086,717
Derivative assets, at fair value 95,937 188,051    
Derivative liabilities, at fair value 11,058 6,740    
Fair Value, Recurring [Member]        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Available-for-sale securities 14,650,922 31,406,328    
Mortgage servicing rights 1,596,153 1,909,444    
Derivative assets, at fair value 95,937 188,051    
Total assets 16,343,012 33,503,823    
Derivative liabilities, at fair value 11,058 6,740    
Total liabilities 11,058 6,740    
Fair Value, 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 33,737 8,513    
Total assets 33,737 8,513    
Derivative liabilities, at fair value 10,462 6,711    
Total liabilities 10,462 6,711    
Fair Value, 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 14,637,891 31,157,154    
Mortgage servicing rights 0 0    
Derivative assets, at fair value 62,200 179,538    
Total assets 14,700,091 31,336,692    
Derivative liabilities, at fair value 596 29    
Total liabilities 596 29    
Fair Value, 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 13,031 249,174    
Mortgage servicing rights 1,596,153 1,909,444    
Derivative assets, at fair value 0 0    
Total assets 1,609,184 2,158,618    
Derivative liabilities, at fair value 0 0    
Total liabilities $ 0 $ 0