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Securities - Contractural Maturities (Details) - USD ($) $ in Thousands | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2019 | Dec. 31, 2018
Securities Available-for-Sale, Amortized Cost |  |  |
Due in one year or less | $ 736 |  |
Due after one year through five years | 4,655 |  |
Due after five years through ten years | 4,645 |  |
Due after ten years | 230,957 |  |
Debt securities excluding securities not due at a single maturity date | 240,993 |  |
Total | $ 474,856 | $ 474,856 | $ 546,867
Securities Available-for-Sale, Weighted Average Yield |  |  |
Due in one year or less (as a percent) | 1.92% |  |
Due after one year through five years (as a percent) | 1.88% |  |
Due after five years through ten years (as a percent) | 3.29% |  |
Due after ten years (as a percent) | 3.04% |  |
Debt securities (as a percent) | 3.02% |  |
Total (as a percent) | 3.31% |  |
Securities Available-for-Sale, Fair Value |  |  |
Due in one year or less | $ 736 |  |
Due after one year through five years | 4,687 |  |
Due after five years through ten years | 4,944 |  |
Due after ten years | 241,541 |  |
Debt securities | 251,908 |  |
Fair Value | 488,422 | 488,422 | 541,248
Collateralized Mortgage Obligations [Member] |  |  |
Securities Available-for-Sale, Amortized Cost |  |  |
Total |  | 62,965 | 66,494
Securities Available-for-Sale, Fair Value |  |  |
Fair Value |  | 64,121 | 64,429
Asset-backed Securities [Member] |  |  |
Securities Available-for-Sale, Amortized Cost |  |  |
Securities not due at a single maturity date | $ 82,106 |  |
Total |  | 82,106 | 108,574
Securities Available-for-Sale, Weighted Average Yield |  |  |
Securities not due at a single maturity date, Weighted Average Yield (as a percent) | 3.27% |  |
Securities Available-for-Sale, Fair Value |  |  |
Securities not due at a single maturity date | $ 83,182 |  |
Fair Value |  | 83,182 | 109,514
Collateralized loan obligations |  |  |
Securities Available-for-Sale, Amortized Cost |  |  |
Securities not due at a single maturity date | $ 72,454 |  |
Total |  | 72,454 | 65,162
Securities Available-for-Sale, Weighted Average Yield |  |  |
Securities not due at a single maturity date, Weighted Average Yield (as a percent) | 4.53% |  |
Securities Available-for-Sale, Fair Value |  |  |
Securities not due at a single maturity date | $ 72,271 |  |
Fair Value |  | $ 72,271 | $ 64,289
Mortgage-backed and collateralized mortgage obligations |  |  |
Securities Available-for-Sale, Amortized Cost |  |  |
Securities not due at a single maturity date | $ 79,303 |  |
Securities Available-for-Sale, Weighted Average Yield |  |  |
Securities not due at a single maturity date, Weighted Average Yield (as a percent) | 3.15% |  |
Securities Available-for-Sale, Fair Value |  |  |
Securities not due at a single maturity date | $ 81,061 |  |

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- Definition Represents the weighted average yield of available-for-sale debt securities maturing after the tenth rolling twelve months following the latest balance sheet presented. This item represents the weighted average yield of all debt securities grouped by maturity dates, excluding the securities with no single maturity date. + References No definition available. + Details
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