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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