Quarterly report pursuant to Section 13 or 15(d)

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

v3.5.0.2
Schedule of Available-for-sale Securities Reconciliation (Details) - USD ($)
$ in Thousands
Jun. 30, 2016
Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value $ 16,335,882 $ 10,912,411
Available-for-sale Securities, Unamortized Premium 567,877 394,787
Available-for-sale Securities, Designated Credit Reserve (335,861) (409,077)
Available-for-sale Securities, Net, Unamortized (3,427,923) (3,429,000)
Available-for-sale Securities, Amortized Cost Basis 13,139,975 7,469,121
Available-for-sale Securities, Gross Unrealized Gains 550,285 427,595
Available-for-sale Securities, Gross Unrealized Losses (33,650) (71,396)
Available-for-sale securities, at fair value 13,656,610 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 13,919,683 8,257,030
Available-for-sale Securities, Unamortized Premium 567,877 394,787
Available-for-sale Securities, Designated Credit Reserve 0 0
Available-for-sale Securities, Net, Unamortized (2,686,818) (2,721,979)
Available-for-sale Securities, Amortized Cost Basis 11,800,742 5,929,838
Available-for-sale Securities, Gross Unrealized Gains 234,394 98,389
Available-for-sale Securities, Gross Unrealized Losses (25,767) (55,337)
Available-for-sale securities, at fair value 12,009,369 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 2,416,199 2,655,381
Available-for-sale Securities, Unamortized Premium 0 0
Available-for-sale Securities, Designated Credit Reserve (335,861) (409,077)
Available-for-sale Securities, Net, Unamortized (741,105) (707,021)
Available-for-sale Securities, Amortized Cost Basis 1,339,233 1,539,283
Available-for-sale Securities, Gross Unrealized Gains 315,891 329,206
Available-for-sale Securities, Gross Unrealized Losses (7,883) (16,059)
Available-for-sale securities, at fair value $ 1,647,241 $ 1,852,430