Securities - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Proceeds from sales of securities available for sale	$ 0	$ 0
Allowance for credit losses - held to maturity securities	$ 32,000		$ 32,000
Amortized cost of debt securities held to maturity rated A or higher by rating agencies (percent)	99.99%
Secure government, public and trust deposits
Debt Securities, Available-for-sale [Line Items]
Available for sale securities pledged as collateral	$ 879,751,000		824,417,000
Short-term borrowings
Debt Securities, Available-for-sale [Line Items]
Available for sale securities pledged as collateral	$ 15,549,000		$ 18,184,000

Debt Securities, Held To maturity, In Amortized Cost Of Rated Agencies' Percentage

No definition available.

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- Definition

Amount of restricted 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 210
-Section 45
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=120413173&loc=SL6242262-115580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
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-SubTopic 210
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=127002003&loc=SL6242269-115581

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- Definition

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
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- Definition

Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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-SubTopic 10
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- Definition

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.

+ References

No definition available.

+ Details

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