v3.8.0.1

Securities - Summary of AFS Securities Portfolio (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized cost | $ 526,560 | $ 518,491
Gross Unrealized gains | 2,098 | 871
Gross Unrealized losses | (9,294) | (9,784)
Estimated Fair Value | 519,364 | 509,578
U.S. Treasury Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized cost | 499 | 300
Gross Unrealized losses | (6) | (3)
Estimated Fair Value | 493 | 297
Agency Mortgage-backed Securities |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized cost | 471,131 | 476,163
Gross Unrealized gains | 287 | 160
Gross Unrealized losses | (7,399) | (7,414)
Estimated Fair Value | 464,019 | 468,909
Beneficial interest - FHLMC securitization |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized cost | 35,930 | 42,028
Gross Unrealized gains | 1,811 | 711
Gross Unrealized losses | (1,889) | (2,367)
Estimated Fair Value | 35,852 | $ 40,372
Corporate Bonds |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Amortized cost | 19,000 |
Estimated Fair Value | $ 19,000 |

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