Annual report pursuant to Section 13 and 15(d)

Fair Value Fair Value, Measurement Inputs, Disclosure (Details)

v2.4.0.6
Fair Value Fair Value, Measurement Inputs, Disclosure (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2012
Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Trading Securities Categorized as Level 1 Assets 100.00%  
Avaialble-for-sale Securities Categorized as Level 2 Assets 99.90%  
Assets Reported at Fair Value, Available-for-sale Securities 88.00%  
Assets Reported at Fair Value, Trading Securities 6.50%  
Equity Securities Categorized as Level 1 Assets 100.00%  
Mortgage Loans Held-for-sale Categorized as Level 2 Assets 100.00%  
Interest Rate Swaps, Swaptions and Credit Default Swaps Categorized as Level 2 Assets (Liabilities) 100.00%  
Inverse Interest-only Securities Categorized as Level 2 Assets 100.00%  
Agency To-be-Announced Securities Categoized as Level 1 Assets (Liabilities) 100.00%  
Forward Purchase Commitments Categorized as Level 3 Assets 100.00%  
Equity securities, at fair value $ 335,638 $ 0
Fair Value, Measurements, Recurring [Member]
   
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available-for-sale Securities, Fair Value Disclosure 13,666,954 6,249,252
Trading Securities, Fair Value Disclosure 1,002,062 1,003,301
Equity securities, at fair value 335,638  
Mortgages Held-for-sale, Fair Value Disclosure 58,607 5,782
Derivative Assets 462,080 251,856
Assets, Fair Value Disclosure 15,525,341 7,510,191
Derivative Financial Instruments, Liabilities, Fair Value Disclosure 129,294 49,080
Liabilities, Fair Value Disclosure 129,294 49,080
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
   
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available-for-sale Securities, Fair Value Disclosure 0 0
Trading Securities, Fair Value Disclosure 1,002,062 1,003,301
Equity securities, at fair value 335,638  
Mortgages Held-for-sale, Fair Value Disclosure 0 0
Derivative Assets 1,917 2,664
Assets, Fair Value Disclosure 1,339,617 1,005,965
Derivative Financial Instruments, Liabilities, Fair Value Disclosure 239 5,652
Liabilities, Fair Value Disclosure 239 5,652
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
   
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available-for-sale Securities, Fair Value Disclosure 13,665,083 6,238,136
Trading Securities, Fair Value Disclosure 0 0
Equity securities, at fair value 0  
Mortgages Held-for-sale, Fair Value Disclosure 58,607 0
Derivative Assets 460,163 249,192
Assets, Fair Value Disclosure 14,183,853 6,487,328
Derivative Financial Instruments, Liabilities, Fair Value Disclosure 129,055 43,428
Liabilities, Fair Value Disclosure 129,055 43,428
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
   
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Available-for-sale Securities, Fair Value Disclosure 1,871 11,116
Trading Securities, Fair Value Disclosure 0 0
Equity securities, at fair value 0  
Mortgages Held-for-sale, Fair Value Disclosure 0 5,782
Derivative Assets 0 0
Assets, Fair Value Disclosure 1,871 16,898
Derivative Financial Instruments, Liabilities, Fair Value Disclosure 0 0
Liabilities, Fair Value Disclosure $ 0 $ 0