v3.21.1

Debt Securities - Investments Classified by Contractual Maturity (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Amortized Cost |  |
Due in one year or less, amortized cost | $ 35,751 |
Due after one year through five years, amortized cost | 304,392 |
Due after five years through ten years, amortized cost | 418,530 |
Due after ten years, amortized cost | 337,130 |
Total maturing securities, amortized cost | 1,095,803 |
Amortized Cost | 1,891,427 | $ 1,624,103
Fair Value |  |
Due in one year or less, estimated fair value | 36,169 |
Due after one year through five years, estimated fair value | 310,792 |
Due after five years through ten years, estimated fair value | 416,063 |
Due after ten years, estimated fair value | 338,884 |
Total maturing securities, fair value | 1,101,908 |
Debt securities available for sale at fair value | 1,896,894 | 1,657,381
Mortgage-backed securities |  |
Amortized Cost |  |
Amortized Cost | 78,512 | 92,261
Fair Value |  |
Debt securities available for sale at fair value | 79,005 | 94,018
Collateralized mortgage obligations |  |
Amortized Cost |  |
Amortized Cost | 717,112 | 559,718
Fair Value |  |
Debt securities available for sale at fair value | $ 715,981 | $ 565,836

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