Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Financial Instruments (Details)

v3.19.1
Fair Value of Financial Instruments (Details) - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Repurchase agreements $ 19,729,691 $ 23,133,476
Long-term Federal Home Loan Bank Advances 50,000  
Revolving credit facilities 375,294 310,000
Maturity Over One Year [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Revolving credit facilities 355,294 290,000
Maturity Over One Year [Member]    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Repurchase agreements $ 300,000 $ 300,000