Investment Securities - Income Earned on Securities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Non-taxable:
Total	$ 48,751	$ 37,848	$ 97,525	$ 71,560
Held-to-maturity
Taxable:
Taxable	11,058	10,578	22,071	12,490
Non-taxable:
Non-taxable	10,225	10,088	20,351	16,190
Available-for-sale
Taxable:
Taxable	21,687	11,217	43,478	27,453
Non-taxable:
Non-taxable	$ 5,781	$ 5,965	$ 11,625	$ 15,427

Interest income, securities, operating, by non-0taxable status [abstract]

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (a)
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
-Subparagraph (1)
-Publisher SEC

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

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-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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