XML 103 R88.htm IDEA: XBRL DOCUMENT v3.20.4
Borrowed Funds - Details of Repurchase Agreements (Details) - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Debt Instrument [Line Items]    
Contractual Maturity Over 90 days, amount $ 800,000 $ 800,000
Maturity Greater than 90 Days [Member]    
Debt Instrument [Line Items]    
Contractual Maturity Over 90 days, amount $ 800,000  
Contractual Maturity Over 90 days, Weighted Average Interest Rate 2.24%  
Mortgage-Related Securities | Maturity Greater than 90 Days [Member]    
Debt Instrument [Line Items]    
Contractual Maturity Over 90 days, Amortized Cost $ 286,198  
Contractual Maturity Over 90 days, Fair Value 304,261  
U.S. Treasury and GSE Obligations | Maturity Greater than 90 Days [Member]    
Debt Instrument [Line Items]    
Contractual Maturity Over 90 days, Amortized Cost 571,182  
Contractual Maturity Over 90 days, Fair Value $ 573,344