Securities - Schedule of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Amortized Cost
Due in one year or less	$ 3,473
Due after one year through five years	20,399
Due after five years through ten years	76,417
Due after ten years	851,128
Amortized Cost	2,072,913	$ 1,869,198
Fair Value
Due in one year or less	3,499
Due after one year through five years	20,755
Due after five years through ten years	77,310
Due after ten years	778,305
Fair Value	1,923,620	1,889,617
MBS/CMO
Amortized Cost
Securities without single maturity	890,290
Amortized Cost	890,290	797,693
Fair Value
Securities without single maturity	828,304
Fair Value	828,304	791,950
US Gov’t Sponsored Entities & Agencies
Amortized Cost
Securities without single maturity	231,206
Amortized Cost	231,206	175,457
Fair Value
Securities without single maturity	215,447
Fair Value	$ 215,447	$ 171,961

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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