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
Mar. 31, 2012
Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Gross Unrealized Gains $ 191,460 $ 120,745
Available-for-sale Securities, Gross Unrealized Losses 106,266 179,461
Available-for-sale securities, at fair value 9,171,511 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 7,722,200 5,692,754
Available-for-sale Securities, Unamortized Premium 458,949 279,640
Available-for-sale Securities, Designated Credit Reserve 0 0
Available-for-sale Securities, Net, Unamortized (1,074,953) (1,008,780)
Available-for-sale Securities, Amortized Cost Basis 7,106,196 4,963,614
Available-for-sale Securities, Gross Unrealized Gains 142,484 108,864
Available-for-sale Securities, Gross Unrealized Losses (21,074) (19,321)
Available-for-sale securities, at fair value 7,227,606 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 4,233,247 2,667,929
Available-for-sale Securities, Unamortized Premium 0 0
Available-for-sale Securities, Designated Credit Reserve (1,304,753) (782,606)
Available-for-sale Securities, Net, Unamortized (948,373) (540,969)
Available-for-sale Securities, Amortized Cost Basis 1,980,121 1,344,354
Available-for-sale Securities, Gross Unrealized Gains 48,976 11,881
Available-for-sale Securities, Gross Unrealized Losses (85,192) (160,140)
Available-for-sale securities, at fair value 1,943,905 1,196,095
Collateralized Mortgage Backed Securities [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Available-for-sale Securities, Face Value 11,955,447 8,360,683
Available-for-sale Securities, Unamortized Premium 458,949 279,640
Available-for-sale Securities, Designated Credit Reserve (1,304,753) (782,606)
Available-for-sale Securities, Net, Unamortized (2,023,326) (1,549,749)
Available-for-sale Securities, Amortized Cost Basis 9,086,317 6,307,968
Available-for-sale Securities, Gross Unrealized Gains 191,460 120,745
Available-for-sale Securities, Gross Unrealized Losses (106,266) (179,461)
Available-for-sale securities, at fair value $ 9,171,511 $ 6,249,252