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Debt Securities Held-to-Maturity | 3 Months Ended
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Mar. 31, 2019
Investments, Debt and Equity Securities [Abstract] |
Debt Securities Held-to-Maturity | Debt Securities Held-to-Maturity The following is a summary of debt securities held-to-maturity at March 31, 2019, and December 31, 2018 (in thousands):
| March 31, 2019
| Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |
Pass-through certificates: |  |  |  |  |  |  |  |  |  |  |
GSEs | $ | 9,448 |  |  | $ | — |  |  | $ | 128 |  |  | $ | 9,320 |
Total securities held-to-maturity | $ | 9,448 |  |  | $ | — |  |  | $ | 128 |  |  | $ | 9,320 |
| December 31, 2018
| Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |
Pass-through certificates: |  |  |  |  |  |  |  |  |  |  |
GSEs | $ | 9,505 |  |  | $ | — |  |  | $ | 256 |  |  | $ | 9,249 |
Total securities held-to-maturity | $ | 9,505 |  |  | $ | — |  |  | $ | 256 |  |  | $ | 9,249 |
Contractual maturities for mortgage-backed securities are not presented, 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. There were no sales of held-to-maturity securities for the three months ended March 31, 2019, or March 31, 2018. At March 31, 2019, debt securities held-to-maturity with a carrying value of $6.4 million were pledged to secure borrowings and deposits. Gross unrealized losses on mortgage-backed securities held-to-maturity, and the estimated fair value of the related securities, aggregated by security category and length of time that individual securities have been in a continuous unrealized loss position, at March 31, 2019 and December 31, 2018, were as follows (in thousands):
| March 31, 2019
| Less than 12 months |  | 12 months or more |  | Total
| Unrealized losses |  | Estimated fair value |  | Unrealized losses |  | Estimated fair value |  | Unrealized losses |  | Estimated fair value
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |
Pass-through certificates: |  |  |  |  |  |  |  |  |  |  |
GSEs | $ | — |  |  | $ | — |  |  | $ | 128 |  |  | $ | 9,320 |  |  | $ | 128 |  |  | $ | 9,320 |
Total securities held-to-maturity | $ | — |  |  | $ | — |  |  | $ | 128 |  |  | $ | 9,320 |  |  | $ | 128 |  |  | $ | 9,320 |
| December 31, 2018
| Less than 12 months |  | 12 months or more |  | Total
| Unrealized losses |  | Estimated fair value |  | Unrealized losses |  | Estimated fair value |  | Unrealized losses |  | Estimated fair value
Mortgage-backed securities: |  |  |  |  |  |  |  |  |  |  |
Pass-through certificates: |  |  |  |  |  |  |  |  |  |  |
GSEs | $ | 34 |  |  | $ | 2,133 |  |  | $ | 222 |  |  | $ | 7,116 |  |  | $ | 256 |  |  | $ | 9,249 |
Total securities held-to-maturity | $ | 34 |  |  | $ | 2,133 |  |  | $ | 222 |  |  | $ | 7,116 |  |  | $ | 256 |  |  | $ | 9,249 |
The Company held six pass-through mortgage-backed securities held-to-maturity, issued or guaranteed by GSEs, all of which were in a continuous unrealized loss position of greater than twelve months at March 31, 2019. Management evaluated these securities and concluded that the declines in value relate to the general interest rate environment and are considered temporary. The securities cannot be prepaid in a manner that would result in the Company not receiving substantially all of its amortized cost. The Company neither has an intent to sell, nor is it more likely than not that the Company will be required to sell, the securities before the recovery of their amortized cost basis or, if necessary, maturity. The fair values of our debt securities held-to-maturity 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. The Company did no t recognize any other-than-temporary impairment charges in earnings on securities held-to-maturity during the three months ended March 31, 2019, or March 31, 2018.

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