Investments - Revenue and General Obligation Bonds (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2022 USD ($) item state	Dec. 31, 2021 USD ($) item state
Debt Securities, Available-for-sale [Line Items]
Investment securities available for sale (before ASU 2016-13)		$ 973,314
Investment securities available for sale	$ 1,069,434
Number of municipal bond \| item	503	403
Various Township Facilities, Charter Township of Washington [Member]
Debt Securities, Available-for-sale [Line Items]
Investment securities available for sale (before ASU 2016-13)		$ 4,000
Number of municipal bond \| item		3
States and Political Subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Investment securities available for sale (before ASU 2016-13)		$ 304,268
Investment securities available for sale	$ 320,729
Fair market value (available-for-sale securities and held-to-maturity securities)	$ 363,118
Investment Portfolio, Securities Issued, Municipalities and Agencies, Number \| item	415	335
Investment Portfolio, Securities Issued, States, Number \| state	37	33
General Obligation Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Investment securities available for sale (before ASU 2016-13)		$ 259,682
Fair market value (available-for-sale securities and held-to-maturity securities)	$ 313,684
General Obligation Bonds [Member] \| City of New York [Member]
Debt Securities, Available-for-sale [Line Items]
Investment securities available for sale	5,000
Subordinate Debenture [Member]
Debt Securities, Available-for-sale [Line Items]
Investment securities available for sale (before ASU 2016-13)		$ 28,500
Investment securities available for sale	$ 54,300
Number of subordinated debentures owned \| item	46	23

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Investment Portfolio, Securities Issued, Municipalities and Agencies, Number

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Investment Portfolio, Securities Issued, States, Number

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Number of municipal bond.

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Number of subordinated debentures owned.

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Topic 320
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-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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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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