Securities - Schedule of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Amortized Cost
Due in one year or less	$ 4,154
Due after one year through five years	14,968
Due after five years through ten years	56,769
Due after ten years	843,779
Amortized Cost	1,961,667	$ 2,094,826
Fair Value
Due in one year or less	4,156
Due after one year through five years	15,055
Due after five years through ten years	55,364
Due after ten years	708,050
Fair Value	1,670,256	1,761,669
MBS/CMO
Amortized Cost
Securities without single maturity	811,898
Amortized Cost	811,898	846,519
Fair Value
Securities without single maturity	692,356
Fair Value	692,356	714,681
US Gov’t Sponsored Entities & Agencies
Amortized Cost
Securities without single maturity	230,099
Amortized Cost	230,099	245,017
Fair Value
Securities without single maturity	195,275
Fair Value	$ 195,275	$ 205,017

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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