Quarterly report pursuant to Section 13 or 15(d)

Schedule of Available-for-sale Securities Reconciliation (Details)

v3.4.0.3
Schedule of Available-for-sale Securities Reconciliation (Details) - USD ($)
$ in Thousands
Mar. 31, 2016
Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value $ 12,425,614 $ 10,912,411
Available-for-sale Securities, Unamortized Premium 462,545 394,787
Available-for-sale Securities, Designated Credit Reserve (353,076) (409,077)
Available-for-sale Securities, Net, Unamortized (3,329,334) (3,429,000)
Available-for-sale Securities, Amortized Cost Basis 9,205,749 7,469,121
Available-for-sale Securities, Gross Unrealized Gains 427,618 427,595
Available-for-sale Securities, Gross Unrealized Losses (48,913) (71,396)
Available-for-sale securities, at fair value 9,584,454 7,825,320
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value 10,080,013 8,257,030
Available-for-sale Securities, Unamortized Premium 462,545 394,787
Available-for-sale Securities, Designated Credit Reserve 0 0
Available-for-sale Securities, Net, Unamortized (2,649,932) (2,721,979)
Available-for-sale Securities, Amortized Cost Basis 7,892,626 5,929,838
Available-for-sale Securities, Gross Unrealized Gains 147,958 98,389
Available-for-sale Securities, Gross Unrealized Losses (31,488) (55,337)
Available-for-sale securities, at fair value 8,009,096 5,972,890
Mortgage-backed Securities, Issued by Private Enterprises [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value 2,345,601 2,655,381
Available-for-sale Securities, Unamortized Premium 0 0
Available-for-sale Securities, Designated Credit Reserve (353,076) (409,077)
Available-for-sale Securities, Net, Unamortized (679,402) (707,021)
Available-for-sale Securities, Amortized Cost Basis 1,313,123 1,539,283
Available-for-sale Securities, Gross Unrealized Gains 279,660 329,206
Available-for-sale Securities, Gross Unrealized Losses (17,425) (16,059)
Available-for-sale securities, at fair value $ 1,575,358 $ 1,852,430