Quarterly report pursuant to Section 13 or 15(d)

Repurchase Agreements Schedule of Repurchase Agreements by Term, Short or Long (Details)

v3.7.0.1
Repurchase Agreements Schedule of Repurchase Agreements by Term, Short or Long (Details) - USD ($)
$ in Thousands
Mar. 31, 2017
Dec. 31, 2016
Assets Sold under Agreements to Repurchase [Line Items]    
Repurchase agreements $ 13,640,720 $ 9,316,351
Maturity up to One Year [Member]    
Assets Sold under Agreements to Repurchase [Line Items]    
Repurchase agreements 13,425,455 9,130,717
Maturity Over One Year [Member]    
Assets Sold under Agreements to Repurchase [Line Items]    
Repurchase agreements $ 215,265 $ 185,634