Quarterly report pursuant to Section 13 or 15(d)

Schedule of Repurchase Agreements by Collateral Type (Details)

v2.4.0.8
Schedule of Repurchase Agreements by Collateral Type (Details) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2014
Dec. 31, 2013
Assets Sold under Agreements to Repurchase [Line Items]    
Assets Sold under Agreements to Repurchase, Repurchase Liability $ 12,021,177 $ 12,250,450
Assets Sold under Agreements to Repurchase, Weighted Average Borrowing Rate, Excluding U.S. Treasuries and Interest Rate Swaps 0.69% 0.75%
Assets Sold under Agreements to Repurchase, Weighted Average Remaining Maturity, Excluding U.S. Treasuries and Interest Rate Swaps 84 72
Assets Sold under Agreements to Repurchase, Interest Rate 0.64% 0.69%
US Treasury Securities [Member]
    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets Sold under Agreements to Repurchase, Repurchase Liability 996,250 997,500
Assets Sold under Agreements to Repurchase, Interest Rate 0.09% 0.03%
US Government Agencies Debt Securities [Member]
    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets Sold under Agreements to Repurchase, Repurchase Liability 8,968,708 9,109,510
Assets Sold under Agreements to Repurchase, Interest Rate 0.41% 0.46%
Mortgage-backed Securities, Issued by Private Enterprises [Member]
    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets Sold under Agreements to Repurchase, Repurchase Liability 1,802,594 1,829,709
Assets Sold under Agreements to Repurchase, Interest Rate 1.96% 2.01%
Inverse Interest-Only Securities [Member]
    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets Sold under Agreements to Repurchase, Repurchase Liability 157,397 166,438
Assets Sold under Agreements to Repurchase, Interest Rate 1.04% 1.05%
Loans Held-for-sale, Mortgages [Member]
    
Assets Sold under Agreements to Repurchase [Line Items]    
Assets Sold under Agreements to Repurchase, Repurchase Liability $ 96,228 $ 147,293
Assets Sold under Agreements to Repurchase, Interest Rate 2.55% 2.85%