Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments and Hedging Activities Schedule of Interest Rate Swaps Associated with TBA Contracts and MSRs (Details)

v2.4.0.8
Derivative Instruments and Hedging Activities Schedule of Interest Rate Swaps Associated with TBA Contracts and MSRs (Details) (Interest Rate Swaps Associated with TBA Contracts and MSRs [Member], USD $)
In Thousands, unless otherwise specified
Sep. 30, 2013
Dec. 31, 2012
Derivative [Line Items]    
Derivative, Notional Amount $ 2,475,000 $ 500,000
Derivative, Average Fixed Interest Rate 1.609%  
Derivative, Average Variable Interest Rate 0.266%  
Derivative, Weighted Average Remaining Maturity 5.284  
Derivative Maturity Within One Year From Balance Sheet Date [Member]
    
Derivative [Line Items]    
Derivative, Notional Amount 0  
Derivative, Average Fixed Interest Rate 0.00%  
Derivative, Average Variable Interest Rate 0.00%  
Derivative, Weighted Average Remaining Maturity 0  
Derivative Maturity Over Four Years From Balance Sheet Date [Member]
    
Derivative [Line Items]    
Derivative, Notional Amount 1,725,000  
Derivative, Average Fixed Interest Rate 1.981%  
Derivative, Average Variable Interest Rate 0.266%  
Derivative, Weighted Average Remaining Maturity 6.359  
Derivative Maturity Over Two And Within Three Years From Balance Sheet Date [Member]
    
Derivative [Line Items]    
Derivative, Notional Amount 0 500,000
Derivative, Average Fixed Interest Rate 0.00% 0.399%
Derivative, Average Variable Interest Rate 0.00% 0.356%
Derivative, Weighted Average Remaining Maturity 0 1.775
Derivative Maturity Over Two And Within Three Years From Balance Sheet Date [Member]
    
Derivative [Line Items]    
Derivative, Notional Amount 750,000  
Derivative, Average Fixed Interest Rate 0.754%  
Derivative, Average Variable Interest Rate 0.266%  
Derivative, Weighted Average Remaining Maturity 2.812  
Derivative Maturity Over Three And Within Four Years From Balance Sheet Date [Member]
    
Derivative [Line Items]    
Derivative, Notional Amount $ 0  
Derivative, Average Fixed Interest Rate 0.00%  
Derivative, Average Variable Interest Rate 0.00%  
Derivative, Weighted Average Remaining Maturity 0