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Securities Held to Maturity | 6 Months Ended
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Jun. 30, 2015
Investments, Debt and Equity Securities [Abstract] |
Securities Held-to-Maturity | Securities Held-to-Maturity The following is a summary of mortgage-backed securities held-to-maturity at June 30, 2015, and December 31, 2014 (in thousands).
| June 30, 2015
| Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |
Pass-through certificates: |  |  |  |  |  |  |  |  |  |  |
GSEs | $ | 3,921 |  |  | $ | 44 |  |  | $ | — |  |  | $ | 3,965 |
Total securities held-to-maturity | $ | 3,921 |  |  | $ | 44 |  |  | $ | — |  |  | $ | 3,965 |
| December 31, 2014
| Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |
Pass-through certificates: |  |  |  |  |  |  |  |  |  |  |
GSEs | $ | 3,609 |  |  | $ | 82 |  |  | $ | — |  |  | $ | 3,691 |
Total securities held-to-maturity | $ | 3,609 |  |  | $ | 82 |  |  | $ | — |  |  | $ | 3,691 |
Contractual maturities for mortgage-backed securities are not included above, as expected maturities on mortgage‑backed securities may differ from contractual maturities as borrowers may have the right to call or prepay obligations with or without penalties. The Company had no held-to-maturity securities at June 30, 2015, or December 31, 2014, that were in an unrealized loss position. The fair values of our investment securities could decline in the future if the underlying performance of the collateral for the collateralized mortgage obligations or other securities deteriorates and our credit enhancement levels do not provide sufficient protections to our contractual principal and interest. As a result, there is a risk that significant other-than-temporary impairments may occur in the future given the current economic environment.

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