Investment Securities - Allowance for Credit Losses AFS (Details) $ in Thousands	3 Months Ended
Mar. 31, 2023 USD ($)
Available-for-sale
Beginning balance	$ 0
Provision for credit loss expense	12,800
Securities charged-off	(7,000)
Ending balance	5,800
State and political subdivisions
Available-for-sale
Beginning balance	0
Provision for credit loss expense	0
Securities charged-off	0
Ending balance	0
Other securities
Available-for-sale
Beginning balance	0
Provision for credit loss expense	12,800
Securities charged-off	(7,000)
Ending balance	$ 5,800

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from writeoff.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479106/326-30-50-9

+ Details

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- Definition

Amount, excluding accrued interest, of reversal of credit loss expense on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) transferred out of available-for-sale into investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 8B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-8B

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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