Fair Value Measurements - Recurring (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Assets:
Securities available-for-sale	$ 1,609,759	$ 1,693,632
Mortgage servicing rights	11,461	7,097
U.S. Treasury
Assets:
Securities available-for-sale	211,097	202,339
U.S. government agencies
Assets:
Securities available-for-sale	55,963	61,888
States and political subdivisions
Assets:
Securities available-for-sale	224,259	257,609
Corporate bonds
Assets:
Securities available-for-sale	9,544	9,887
Collateralized mortgage obligations
Assets:
Securities available-for-sale	587,846	672,967
Asset-backed Securities
Assets:
Securities available-for-sale	219,587	236,877
Collateralized loan obligations.
Assets:
Securities available-for-sale	173,837	79,763
Fair Value, Inputs, Level 1 [Member]
Assets:
Securities available-for-sale	211,097	202,339
Fair Value, Inputs, Level 2 [Member]
Assets:
Securities available-for-sale	1,385,353	1,476,057
Loans held-for-sale	1,297	4,737
Other assets	6,602	3,494
Liabilities:
Other liabilities	12,277	6,788
Fair Value, Inputs, Level 3 [Member]
Assets:
Securities available-for-sale	13,309	15,236
Mortgage servicing rights	11,461	7,097
Fair Value, Measurements, Recurring [Member]
Assets:
Loans held-for-sale	1,297	4,737
Mortgage servicing rights	11,461	7,097
Total financial assets	1,629,329	1,709,468
Liabilities:
Total	12,278	6,809
Fair Value, Measurements, Recurring [Member] \| Interest rate swap agreements, including risk participation agreement
Assets:
Other assets	6,624	3,494
Liabilities:
Other liabilities	12,278	6,809
Fair Value, Measurements, Recurring [Member] \| Forward Contracts [Member]
Assets:
Other assets	188	508
Fair Value, Measurements, Recurring [Member] \| U.S. Treasury
Assets:
Securities available-for-sale	211,097	202,339
Fair Value, Measurements, Recurring [Member] \| U.S. government agencies
Assets:
Securities available-for-sale	55,963	61,888
Fair Value, Measurements, Recurring [Member] \| Mortgage Backed Securities, Issued by US Government Agencies
Assets:
Securities available-for-sale	127,626	172,302
Fair Value, Measurements, Recurring [Member] \| States and political subdivisions
Assets:
Securities available-for-sale	224,259	257,609
Fair Value, Measurements, Recurring [Member] \| Corporate bonds
Assets:
Securities available-for-sale	9,544	9,887
Fair Value, Measurements, Recurring [Member] \| Collateralized mortgage obligations
Assets:
Securities available-for-sale	587,846	672,967
Fair Value, Measurements, Recurring [Member] \| Asset-backed Securities
Assets:
Securities available-for-sale	219,587	236,877
Fair Value, Measurements, Recurring [Member] \| Collateralized loan obligations.
Assets:
Securities available-for-sale	173,837	79,763
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets:
Total financial assets	211,097	202,339
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| U.S. Treasury
Assets:
Securities available-for-sale	211,097	202,339
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets:
Loans held-for-sale	1,297	4,737
Total financial assets	1,393,462	1,484,796
Liabilities:
Total	12,278	6,809
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest rate swap agreements, including risk participation agreement
Assets:
Other assets	6,624	3,494
Liabilities:
Other liabilities	12,278	6,809
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Forward Contracts [Member]
Assets:
Other assets	188	508
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| U.S. government agencies
Assets:
Securities available-for-sale	55,963	61,888
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Mortgage Backed Securities, Issued by US Government Agencies
Assets:
Securities available-for-sale	127,626	172,302
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| States and political subdivisions
Assets:
Securities available-for-sale	210,950	242,373
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Corporate bonds
Assets:
Securities available-for-sale	9,544	9,887
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized mortgage obligations
Assets:
Securities available-for-sale	587,846	672,967
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Asset-backed Securities
Assets:
Securities available-for-sale	219,587	236,877
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized loan obligations.
Assets:
Securities available-for-sale	173,837	79,763
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets:
Mortgage servicing rights	11,461	7,097
Total financial assets	24,770	22,333
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| States and political subdivisions
Assets:
Securities available-for-sale	$ 13,309	$ 15,236

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 of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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