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Securities - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended		21 Months Ended
	Sep. 30, 2025	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Dec. 31, 2024
Marketable Securities [Line Items]
Securities available-for-sale, at fair value	$ 511,095,000	$ 511,095,000		$ 511,095,000	$ 482,328,000
Debt Securities, Available-for-Sale, Excluding Accrued Interest	511,095,000	511,095,000		511,095,000	482,328,000
Provision for credit losses, HTM				0
Provision for credit losses, AFS				0
Impairment on other investments		0
Asset Pledged as Collateral | Secure Public Funds and Securities Sold under Agreements to Repurchase
Marketable Securities [Line Items]
Securities available-for-sale, at fair value	404,600,000	404,600,000		404,600,000	432,600,000
Debt Securities, Available-for-Sale, Excluding Accrued Interest	404,600,000	404,600,000		$ 404,600,000	$ 432,600,000
Gross gains	$ 210,000		$ 0
Realized losses		$ 3,900,000	$ 0

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- Definition

Debt securities, available-for-sale, allowance for credit loss, expense reversal.

+ References

No definition available.

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- Definition

Other investments impairment.

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- Definition

Amount excluding accrued interest, of 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/2009/role/commonPracticeRef
-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

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- Definition

Amount of realized gain 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 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

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- Definition

Amount of realized 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 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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