Securities - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Realized gains on available-for-sale debt securities	$ 50,300	$ 0	$ 50,300	$ 0
Realized losses on available-for-sale debt securities	0	62,900,000	0	70,000,000.0
Available-for-sale securities sold	39,900,000	510,500,000	429,600,000	510,500,000
Proceeds from sales of available-for-sale debt securities	40,000,000	366,700,000	39,952,000	440,488,000
Realized gains or losses on called available-for-sale debt securities	0	0	0	0
Net gains (losses) on equity securities	34,700	$ (36,700)	14,300	$ (35,700)
Federal Home Loan Bank New York (FHLBNY)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Holdings of FHLBNY, FHLBPITT and ACBB stock, amount of advances	30,800,000		30,800,000
Atlantic Central Bankers Bank (ACBB)
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Holdings of FHLBNY, FHLBPITT and ACBB stock, amount of advances	$ 95,000		$ 95,000

Debt Securities, Available For Sale, Called, Realized Gain (Loss)

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with interest rate reset through auction process, sold at par value.

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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
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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).

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of advance from Federal Home Loan Bank (FHLBank).

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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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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).

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-SubTopic 10
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