Quarterly report pursuant to Section 13 or 15(d)

Schedule of Underlying Assets of Repurchase Agreements when Amount of Repurchase Agreements Exceeds 10 Percent of Assets (Details)

v3.20.2
Schedule of Underlying Assets of Repurchase Agreements when Amount of Repurchase Agreements Exceeds 10 Percent of Assets (Details) - USD ($)
$ in Thousands
Sep. 30, 2020
Dec. 31, 2019
Assets Sold under Agreements to Repurchase [Line Items]    
Assets pledged or restricted as collateral for repurchase agreements $ 17,107,094 $ 31,196,419
Available-for-sale Securities [Member]    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets pledged or restricted as collateral for repurchase agreements 16,550,904 29,575,948
Mortgage Servicing Rights [Member]    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets pledged or restricted as collateral for repurchase agreements 0 530,222
Restricted Cash and Cash Equivalents [Member]    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets pledged or restricted as collateral for repurchase agreements 456,898 919,010
Due From Counterparties [Member]    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets pledged or restricted as collateral for repurchase agreements 32,507 102,365
Derivative Financial Instruments, Assets [Member]    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets pledged or restricted as collateral for repurchase agreements $ 66,785 $ 68,874