Securities - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Amortized Cost
Due in one year or less	$ 1,807
Due after one year through five years	17,277
Due after five years through ten years	60,985
Due after ten years	812,102
Amortized Cost	1,891,435	$ 2,094,826
Fair Value
Due in one year or less	1,793
Due after one year through five years	16,880
Due after five years through ten years	54,202
Due after ten years	606,312
Fair Value	1,476,956	1,761,669
MBS/CMO
Amortized Cost
Securities without single maturity	775,708
Amortized Cost	775,708	846,519
Fair Value
Securities without single maturity	620,563
Fair Value	620,563	714,681
US Gov’t Sponsored Entities & Agencies
Amortized Cost
Securities without single maturity	223,556
Amortized Cost	223,556	245,017
Fair Value
Securities without single maturity	177,206
Fair Value	$ 177,206	$ 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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-Topic 320
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-Section 50
-Paragraph 3
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-Publisher FASB
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+ References

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

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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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