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Fair Value Measurements (Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis) (Details) - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Trading securities | $ 6,799 | $ 6,422
Measured on a recurring basis: |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 640,212 | 771,239
Trading securities | 6,799 | 6,422
Total | 647,011 | 777,661
Measured on a recurring basis: | GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 606,332 | 699,790
Measured on a recurring basis: | Non-GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 811 | 1,026
Measured on a recurring basis: | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 32,740 | 70,013
Measured on a recurring basis: | Equities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 329 | 410
Measured on a recurring basis: | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 329 | 410
Trading securities | 6,799 | 6,422
Total | 7,128 | 6,832
Measured on a recurring basis: | Quoted Prices in Active Markets for Identical Assets (Level 1) | Equities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 329 | 410
Measured on a recurring basis: | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 639,883 | 770,829
Total | 639,883 | 770,829
Measured on a recurring basis: | Significant Other Observable Inputs (Level 2) | GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 606,332 | 699,790
Measured on a recurring basis: | Significant Other Observable Inputs (Level 2) | Non-GSE |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 811 | 1,026
Measured on a recurring basis: | Significant Other Observable Inputs (Level 2) | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 32,740 | 70,013
Measured on a recurring basis: | Significant Other Observable Inputs (Level 2) | Equities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Mortgage-backed securities: | 0 |
Measured on a non-recurring basis: |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 19,030 | 19,901
Other real estate owned | 423 | 752
Total | 19,453 | 21,093
Measured on a non-recurring basis: | Commercial real estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 15,704 | 17,438
Measured on a non-recurring basis: | One-to-four family residential mortgage |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 1,745 | 672
Measured on a non-recurring basis: | Multifamily |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 1,294 | 1,513
Measured on a non-recurring basis: | Home equity and lines of credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 287 | 278
Measured on a non-recurring basis: | Commercial and Industrial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Commercial and industrial loans |  | 440
Measured on a non-recurring basis: | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 19,030 | 19,901
Other real estate owned | 423 | 752
Total | 19,453 | 21,093
Measured on a non-recurring basis: | Significant Unobservable Inputs (Level 3) | Commercial real estate |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 15,704 | 17,438
Measured on a non-recurring basis: | Significant Unobservable Inputs (Level 3) | One-to-four family residential mortgage |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 1,745 | 672
Measured on a non-recurring basis: | Significant Unobservable Inputs (Level 3) | Multifamily |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | 1,294 | 1,513
Measured on a non-recurring basis: | Significant Unobservable Inputs (Level 3) | Home equity and lines of credit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans: | $ 287 | 278
Measured on a non-recurring basis: | Significant Unobservable Inputs (Level 3) | Commercial and Industrial |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Commercial and industrial loans |  | $ 440

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