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Debt Securities Held-to-Maturity | 6 Months Ended
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Jun. 30, 2020
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 June 30, 2020, and December 31, 2019 (in thousands):
| June 30, 2020 |  |  |  |  |  |
| Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
Mortgage-backed securities: |  |  |  |  |  |  |
Pass-through certificates: |  |  |  |  |  |  |
GSEs | $ | 8,648 |  |  | $ | 370 |  |  | $ | — |  |  | $ | 9,018 |
Total securities held-to-maturity | $ | 8,648 |  |  | $ | 370 |  |  | $ | — |  |  | $ | 9,018 |
| December 31, 2019 |  |  |  |  |  |
| Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
Mortgage-backed securities: |  |  |  |  |  |  |
Pass-through certificates: |  |  |  |  |  |  |
GSEs | $ | 8,762 |  |  | $ | 129 |  |  | $ | 5 |  |  | $ | 8,886 |
Total securities held-to-maturity | $ | 8,762 |  |  | $ | 129 |  |  | $ | 5 |  |  | $ | 8,886 |
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 six months ended June 30, 2020, or June 30, 2019. At June 30, 2020, debt securities held-to-maturity with a carrying value of $7.3 million were pledged to secure borrowings and deposits. At June 30, 2020, there were no debt securities held-to-maturity in an unrealized loss position. 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 December 31, 2019, were as follows (in thousands):
| December 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 | $ | — |  |  | $ | — |  |  | $ | 5 |  |  | $ | 378 |  |  | $ | 5 |  |  | $ | 378 |
Total securities held-to-maturity | $ | — |  |  | $ | — |  |  | $ | 5 |  |  | $ | 378 |  |  | $ | 5 |  |  | $ | 378 |
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 not recognize any other-than-temporary impairment charges in earnings on securities held-to-maturity during the three and six months ended June 30, 2020, or June 30, 2019.

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