Fair Value Measurements and Fair Value of Financial Instruments, Fair Value of Financial Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2022	Dec. 31, 2021
AFS securities [Abstract]
AFS securities	$ 1,619,356	$ 1,687,361
Equity securities	29,974	33,550
Fair Value Measurements [Abstract]
Collateral dependent impaired loans with specific reserve	9,300	10,200
Reserves on collateral dependent impaired loans	$ 800	0
Minimum [Member]
Fair Value Measurements [Abstract]
Liquidation expense ratio on impaired collateral	10.00%
Maximum [Member]
Fair Value Measurements [Abstract]
Liquidation expense ratio on impaired collateral	50.00%
U.S. Treasury [Member]
AFS securities [Abstract]
AFS securities	$ 115,177	73,069
Federal Agency [Member]
AFS securities [Abstract]
AFS securities	217,432	239,931
State & Municipal [Member]
AFS securities [Abstract]
AFS securities	87,959	94,088
Corporate [Member]
AFS securities [Abstract]
AFS securities	53,180	52,003
Recurring Basis [Member]
AFS securities [Abstract]
AFS securities	1,619,356	1,687,361
Equity securities	29,974	33,550
Derivatives	75,675	60,625
Total	1,725,005	1,781,536
Liabilities [Abstract]
Derivatives	75,193	60,263
Total	75,193	60,263
Recurring Basis [Member] \| Level 1 [Member]
AFS securities [Abstract]
AFS securities	115,177	73,069
Equity securities	28,974	32,550
Derivatives	0	0
Total	144,151	105,619
Liabilities [Abstract]
Derivatives	0	0
Total	0	0
Recurring Basis [Member] \| Level 2 [Member]
AFS securities [Abstract]
AFS securities	1,504,179	1,614,292
Equity securities	1,000	1,000
Derivatives	75,675	60,625
Total	1,580,854	1,675,917
Liabilities [Abstract]
Derivatives	75,193	60,263
Total	75,193	60,263
Recurring Basis [Member] \| Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Equity securities	0	0
Derivatives	0	0
Total	0	0
Liabilities [Abstract]
Derivatives	0	0
Total	0	0
Recurring Basis [Member] \| U.S. Treasury [Member]
AFS securities [Abstract]
AFS securities	115,177	73,069
Recurring Basis [Member] \| U.S. Treasury [Member] \| Level 1 [Member]
AFS securities [Abstract]
AFS securities	115,177	73,069
Recurring Basis [Member] \| U.S. Treasury [Member] \| Level 2 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| U.S. Treasury [Member] \| Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| Federal Agency [Member]
AFS securities [Abstract]
AFS securities	217,432	239,931
Recurring Basis [Member] \| Federal Agency [Member] \| Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| Federal Agency [Member] \| Level 2 [Member]
AFS securities [Abstract]
AFS securities	217,432	239,931
Recurring Basis [Member] \| Federal Agency [Member] \| Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| State & Municipal [Member]
AFS securities [Abstract]
AFS securities	87,959	94,088
Recurring Basis [Member] \| State & Municipal [Member] \| Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| State & Municipal [Member] \| Level 2 [Member]
AFS securities [Abstract]
AFS securities	87,959	94,088
Recurring Basis [Member] \| State & Municipal [Member] \| Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| Mortgage-Backed [Member]
AFS securities [Abstract]
AFS securities	522,045	606,675
Recurring Basis [Member] \| Mortgage-Backed [Member] \| Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| Mortgage-Backed [Member] \| Level 2 [Member]
AFS securities [Abstract]
AFS securities	522,045	606,675
Recurring Basis [Member] \| Mortgage-Backed [Member] \| Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| Collateralized Mortgage Obligations [Member]
AFS securities [Abstract]
AFS securities	623,563	621,595
Recurring Basis [Member] \| Collateralized Mortgage Obligations [Member] \| Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| Collateralized Mortgage Obligations [Member] \| Level 2 [Member]
AFS securities [Abstract]
AFS securities	623,563	621,595
Recurring Basis [Member] \| Collateralized Mortgage Obligations [Member] \| Level 3 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| Corporate [Member]
AFS securities [Abstract]
AFS securities	53,180	52,003
Recurring Basis [Member] \| Corporate [Member] \| Level 1 [Member]
AFS securities [Abstract]
AFS securities	0	0
Recurring Basis [Member] \| Corporate [Member] \| Level 2 [Member]
AFS securities [Abstract]
AFS securities	53,180	52,003
Recurring Basis [Member] \| Corporate [Member] \| Level 3 [Member]
AFS securities [Abstract]
AFS securities	$ 0	$ 0

The percentage of liquidation expenses estimated with liquidating impaired collateral.

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Amount of loans considered to be collateral dependent.

+ References

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Amount of specific reserves for loans considered to be collateral dependent.

+ References

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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).

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Fair value of financial and nonfinancial obligations.

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