Held-to-Maturity Securities (Other-Than-Temporary Impairment Analysis) (Details) (USD $) | 3 Months Ended |
In Thousands, unless otherwise specified | Mar. 31, 2014 | Mar. 31, 2013 |
| position |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] | ' | ' |
Held-to-maturity, Qualitative Disclosure, Non Agency RMBS Number of Positions | 29 | ' |
Held-to-maturity, Qualitative Disclosure, Non Agency RMBS Number of Securities, Previously Identified as OTTI not Further Impaired This Period | 14 | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | $128,882 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 116,673 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 94,805 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 63,464 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 85,332 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 109,919 | ' |
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] | ' | ' |
Balance of Credit Losses Recognized in Earnings, beginning of period | 12,901 | 13,039 |
Increase In Cash Flows Expected To Be Collected | -65 | 0 |
Balance of Credit Losses Recognized in Earnings, end of period | 12,836 | 13,039 |
Cumulative Other Than Temporary Impairment Principal Shortfalls | -870 | 0 |
Cumulative Amortization of the Time Value of Credit Losses | 248 | 180 |
OTTI Credit Losses in the Amortized Cost of Held-to-maturity Securities | 12,214 | 13,219 |
Minimum [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities, Portion Recognized in Earnings, Net, Qualitative Disclosures [Abstract] | ' | ' |
Projected House Price Decline Rate Over the Next 12 Months | 3.00% | ' |
Projected Home Price Recovery, One to Six Months, Percent | 0.00% | ' |
Projected Home Price Recovery, Seven to Twelve Months, Percent | 1.00% | ' |
Projected Home Price Recovery, Thirteen to Eighteen Months, Percent | 2.00% | ' |
Projected Home Price Recovery, Nineteen to Thirty Months, Percent | 2.00% | ' |
Projected Home Price Recovery, Thirty One to Fifty Four Months, Percent | 2.00% | ' |
Projected Home Price Recovery, Months Thereafter, Percent | 2.30% | ' |
Maximum [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities, Portion Recognized in Earnings, Net, Qualitative Disclosures [Abstract] | ' | ' |
Projected House Price Recovery Rate Over the Next 12 Months | 9.00% | ' |
Projected Home Price Recovery, One to Six Months, Percent | 3.00% | ' |
Projected Home Price Recovery, Seven to Twelve Months, Percent | 4.00% | ' |
Projected Home Price Recovery, Thirteen to Eighteen Months, Percent | 4.00% | ' |
Projected Home Price Recovery, Nineteen to Thirty Months, Percent | 5.00% | ' |
Projected Home Price Recovery, Thirty One to Fifty Four Months, Percent | 6.00% | ' |
Projected Home Price Recovery, Months Thereafter, Percent | 5.60% | ' |
Q1 2009 [Member] | Private Label Residential Mortgage Backed Securities, Security One [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 12,793 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 10,070 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 10,271 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 7,733 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 7,532 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 10,350 | ' |
Q1 2009 [Member] | Private Label Residential Mortgage Backed Securities, Security Two [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 12,725 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 12,028 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 12,389 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 8,365 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 8,004 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 11,188 | ' |
Q2 2009 [Member] | Private Label Residential Mortgage Backed Securities, Security Three [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Single-D | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 17,946 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 13,902 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 15,283 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 11,517 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 10,136 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 14,723 | ' |
Q2 2009 [Member] | Private Label Residential Mortgage Backed Securities, Security Four [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 8,801 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 8,085 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 7,890 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 5,551 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 5,746 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 7,906 | ' |
Q3 2009 [Member] | Private Label Residential Mortgage Backed Securities, Security Five [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 15,525 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 13,800 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 10,047 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 7,188 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 10,941 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 13,328 | ' |
Q3 2009 [Member] | Private Label Residential Mortgage Backed Securities, Security Six [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 13,400 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 11,995 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 10,567 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 6,988 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 8,416 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 11,151 | ' |
Q3 2009 [Member] | Private Label Residential Mortgage Backed Securities, Security Seven [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Single-B | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 4,789 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 4,709 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 3,575 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 2,268 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 3,402 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 4,288 | ' |
Q1 2010 [Member] | Private Label Residential Mortgage Backed Securities, Security Eight [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 7,172 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 7,149 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 4,968 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 3,058 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 5,239 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 6,326 | ' |
Q1 2010 [Member] | Private Label Residential Mortgage Backed Securities, Security Nine [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 3,061 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 3,024 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 2,208 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 1,362 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 2,178 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 2,711 | ' |
Q4 2010 [Member] | Private Label Residential Mortgage Backed Securities, Security Ten [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 6,041 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 5,616 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 3,331 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 1,663 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 3,948 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 5,135 | ' |
Q4 2010 [Member] | Private Label Residential Mortgage Backed Securities, Security Eleven [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 7,267 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 7,263 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 4,096 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 2,114 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 5,281 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 6,452 | ' |
Q4 2010 [Member] | Private Label Residential Mortgage Backed Securities, Security Twelve [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 4,005 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 3,921 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 1,820 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 917 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 3,018 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 3,517 | ' |
Q4 2010 [Member] | Private Label Residential Mortgage Backed Securities, Security Thirteen [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 4,744 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 4,728 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 2,418 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 1,358 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 3,668 | ' |
Other Than Temporarily Impaired Securities, Fair Value | 4,277 | ' |
Q2 2011 [Member] | Private Label Residential Mortgage Backed Securities, Security Fourteen [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities [Abstract] | ' | ' |
Debt Instrument, Credit Rating | 'Triple-C | ' |
Other Than Temporarily Impaired Securities, Unpaid Principal Balance | 10,613 | ' |
Other Than Temporarily Impaired Securities, Amortized Cost | 10,383 | ' |
Other Than Temporarily Impaired Securities, Cumulative Non-credit Impairment | 5,942 | ' |
Other Than Temporarily Impaired Securities, Cumulative Accretion of Non-credit Impairment | 3,382 | ' |
Other Than Temporarily Impaired Securities, Carrying Value | 7,823 | ' |
Other Than Temporarily Impaired Securities, Fair Value | $8,567 | ' |
Majority of Markets [Member] | Minimum [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities, Portion Recognized in Earnings, Net, Qualitative Disclosures [Abstract] | ' | ' |
Projected House Price Decline Rate Over the Next 12 Months | 1.00% | ' |
Majority of Markets [Member] | Maximum [Member] | ' | ' |
Other than Temporary Impairment Losses, Investments, Held-to-maturity Securities, Portion Recognized in Earnings, Net, Qualitative Disclosures [Abstract] | ' | ' |
Projected House Price Recovery Rate Over the Next 12 Months | 4.00% | ' |