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Securities Available-for-Sale (Narrative) (Details) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2015 USD ($) | Jun. 30, 2014 USD ($) | Jun. 30, 2015 USD ($) security | Jun. 30, 2014 USD ($)
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Proceeds from sale of securities available-for-sale | $ | $ 39,183,000 | $ 6,400,000 | $ 39,226,000 | $ 7,270,000
Gross realized gains on sales of securities available-for-sale | $ | 46,000 | 144,000 | 46,000 | 199,000,000
Gross realized losses on sales of securities available-for-sale | $ | 3,000 | 0 | 3,000 | 0
Recognized gains (losses) on trading securities portfolio | $ | (50,000) | 175,000,000 | 11,000 | 244,000,000
Impairment charges against earnings | $ | $ 0 | $ 0 | $ 0 | $ 0
Continuous Unrealized Loss Position Less Than 12 Months | Non-GSE | Real Estate Mortgage Investment Conduits (REMICs) |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of securities (securities) |  |  | 2 |
Continuous Unrealized Loss Position Less Than 12 Months | Corporate bonds |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of securities (securities) |  |  | 3 |
Pass Through | Continuous Unrealized Loss Position 12 Months Or Longer | GSE | Real Estate Mortgage Investment Conduits (REMICs) |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of securities (securities) |  |  | 11 |
Pass Through | Continuous Unrealized Loss Position Less Than 12 Months | GSE | Pass-through Certificates |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of securities (securities) |  |  | 3 |
Non Pass Through | Continuous Unrealized Loss Position 12 Months Or Longer | GSE | Real Estate Mortgage Investment Conduits (REMICs) |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of securities (securities) |  |  | 12 |
Non Pass Through | Continuous Unrealized Loss Position Less Than 12 Months | GSE | Real Estate Mortgage Investment Conduits (REMICs) |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Number of securities (securities) |  |  | 1 |

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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 + Details
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- Definition The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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- Definition The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26853-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3179-108585 + Details
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