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
Sep. 30, 2016
Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value $ 16,889,556 $ 10,912,411
Available-for-sale Securities, Unamortized Premium 625,519 394,787
Available-for-sale Securities, Designated Credit Reserve (352,489) (409,077)
Available-for-sale Securities, Net, Unamortized (3,410,109) (3,429,000)
Available-for-sale Securities, Amortized Cost Basis 13,752,477 7,469,121
Available-for-sale Securities, Gross Unrealized Gains 568,067 427,595
Available-for-sale Securities, Gross Unrealized Losses (35,919) (71,396)
Available-for-sale securities, at fair value 14,284,625 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 14,254,562 8,257,030
Available-for-sale Securities, Unamortized Premium 625,519 394,787
Available-for-sale Securities, Designated Credit Reserve 0 0
Available-for-sale Securities, Net, Unamortized (2,620,684) (2,721,979)
Available-for-sale Securities, Amortized Cost Basis 12,259,397 5,929,838
Available-for-sale Securities, Gross Unrealized Gains 208,319 98,389
Available-for-sale Securities, Gross Unrealized Losses (30,900) (55,337)
Available-for-sale securities, at fair value 12,436,816 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 2,634,994 2,655,381
Available-for-sale Securities, Unamortized Premium 0 0
Available-for-sale Securities, Designated Credit Reserve (352,489) (409,077)
Available-for-sale Securities, Net, Unamortized (789,425) (707,021)
Available-for-sale Securities, Amortized Cost Basis 1,493,080 1,539,283
Available-for-sale Securities, Gross Unrealized Gains 359,748 329,206
Available-for-sale Securities, Gross Unrealized Losses (5,019) (16,059)
Available-for-sale securities, at fair value $ 1,847,809 $ 1,852,430