Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Amortized Cost
Due in one year or less	$ 51,185
Due after one year through five years	12,108
Due after five years through ten years	50,483
Due after ten years	762,320
Amortized Cost	1,838,911	$ 1,871,260
Fair Value
Due in one year or less	51,185
Due after one year through five years	12,036
Due after five years through ten years	46,605
Due after ten years	628,620
Fair Value	1,539,270	1,596,832
MBS/CMO
Amortized Cost
Securities without single maturity	746,250
Amortized Cost	746,250	761,025
Fair Value
Securities without single maturity	623,016
Fair Value	623,016	645,040
US Gov’t Sponsored Entities & Agencies
Amortized Cost
Securities without single maturity	216,565
Amortized Cost	216,565	220,295
Fair Value
Securities without single maturity	177,808
Fair Value	$ 177,808	$ 182,917

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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-Topic 320
-SubTopic 10
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-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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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 second through fifth 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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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 next 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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+ References

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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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