Quarterly report pursuant to Section 13 or 15(d)

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

v2.4.0.6
Schedule of Available-for-sale Securities Reconciliation (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2012
Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Gross Unrealized Gains $ 730,503 $ 120,745
Available-for-sale Securities, Gross Unrealized Losses 30,107 179,461
Available-for-sale securities, at fair value 14,969,859 6,249,252
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value 13,101,209 5,692,754
Available-for-sale Securities, Unamortized Premium 850,721 279,640
Available-for-sale Securities, Designated Credit Reserve 0 0
Available-for-sale Securities, Net, Unamortized (1,853,894) (1,008,780)
Available-for-sale Securities, Amortized Cost Basis 12,098,036 4,963,614
Available-for-sale Securities, Gross Unrealized Gains 384,523 108,864
Available-for-sale Securities, Gross Unrealized Losses (13,496) (19,321)
Available-for-sale securities, at fair value 12,469,063 5,053,157
Mortgage-backed Securities, Issued by Private Enterprises [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value 4,471,572 2,667,929
Available-for-sale Securities, Unamortized Premium 0 0
Available-for-sale Securities, Designated Credit Reserve (1,339,737) (782,606)
Available-for-sale Securities, Net, Unamortized (960,408) (540,969)
Available-for-sale Securities, Amortized Cost Basis 2,171,427 1,344,354
Available-for-sale Securities, Gross Unrealized Gains 345,980 11,881
Available-for-sale Securities, Gross Unrealized Losses (16,611) (160,140)
Available-for-sale securities, at fair value 2,500,796 1,196,095
Collateralized Mortgage Backed Securities [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value 17,572,781 8,360,683
Available-for-sale Securities, Unamortized Premium 850,721 279,640
Available-for-sale Securities, Designated Credit Reserve (1,339,737) (782,606)
Available-for-sale Securities, Net, Unamortized (2,814,302) (1,549,749)
Available-for-sale Securities, Amortized Cost Basis 14,269,463 6,307,968
Available-for-sale Securities, Gross Unrealized Gains 730,503 120,745
Available-for-sale Securities, Gross Unrealized Losses (30,107) (179,461)
Available-for-sale securities, at fair value $ 14,969,859 $ 6,249,252