Derivative Instruments and Hedging Activities Schedule of Derivative Instruments in Statement of Financial Position, Fair Value (Details) (USD $)
In Thousands, unless otherwise specified |
Jun. 30, 2013
|
Dec. 31, 2012
|
---|---|---|
Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | $ 699,351 | $ 462,080 |
Derivative, Notional Amount | 29,556,972 | 9,768,656 |
Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | (46,028) | (129,294) |
Derivative, Notional Amount | 23,551,633 | 14,209,000 |
Inverse Interest-Only Securities [Member] | Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 245,195 | 304,975 |
Derivative, Notional Amount | 1,798,972 | 1,909,351 |
Inverse Interest-Only Securities [Member] | Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 0 | 0 |
Derivative, Notional Amount | 0 | 0 |
Interest Rate Swap [Member] | Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 142,317 | 0 |
Derivative, Notional Amount | 18,485,000 | 0 |
Interest Rate Swap [Member] | Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 0 | (129,055) |
Derivative, Notional Amount | 0 | 14,070,000 |
Credit Default Swap [Member] | Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 0 | 52,906 |
Derivative, Notional Amount | 0 | 438,440 |
Credit Default Swap [Member] | Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | (8,198) | 0 |
Derivative, Notional Amount | 1,630,404 | 0 |
Interest Rate Swaption [Member] | Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 225,810 | 102,048 |
Derivative, Notional Amount | 6,250,000 | 4,950,000 |
Interest Rate Swaption [Member] | Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 0 | 0 |
Derivative, Notional Amount | 0 | 0 |
Forward Contracts [Member] | Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 61,156 | 1,917 |
Derivative, Notional Amount | 2,813,000 | 2,414,000 |
Forward Contracts [Member] | Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | (22,568) | (239) |
Derivative, Notional Amount | 2,892,000 | 139,000 |
Options Held [Member] | Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 24,873 | |
Derivative, Notional Amount | 210,000 | |
Options Held [Member] | Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 0 | |
Derivative, Notional Amount | 0 | |
Swap [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | (14,058) | |
Derivative, Notional Amount | 19,000,000 | |
Swap [Member] | Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 0 | |
Derivative, Notional Amount | 0 | |
Swap [Member] | Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | (14,058) | |
Derivative, Notional Amount | 19,000,000 | |
Forward Purchase Commitment [Member] | Derivative Financial Instruments, Assets [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | 0 | 234 |
Derivative, Notional Amount | 0 | 56,865 |
Forward Purchase Commitment [Member] | Derivative Financial Instruments, Liabilities [Member]
|
||
Derivatives, Fair Value [Line Items] | ||
Derivative, Fair Value, Net | (1,204) | 0 |
Derivative, Notional Amount | $ 29,229 | $ 0 |