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Fair Value Measurements - Recurring (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Assets:
Securities available-for-sale	$ 1,816,450		$ 1,692,488
Mortgage servicing rights	10,376		7,097
U.S. Treasury
Assets:
Securities available-for-sale	220,563		202,339
U.S. government agencies
Assets:
Securities available-for-sale	59,036		61,888
States and political subdivisions
Assets and liabilities measured at fair value on a recurring basis
Purchases	1,076	$ 58
Assets:
Securities available-for-sale	236,408		256,465
Corporate bonds
Assets:
Securities available-for-sale	9,683		9,887
Collateralized mortgage obligations
Assets:
Securities available-for-sale	696,513		672,967
Asset-backed Securities
Assets:
Securities available-for-sale	274,941		236,877
Collateralized loan obligations.
Assets:
Securities available-for-sale	166,158		79,763
Fair Value, Inputs, Level 1 [Member]
Assets:
Securities available-for-sale	220,563		202,339
Fair Value, Inputs, Level 2 [Member]
Assets:
Securities available-for-sale	1,582,054		1,476,057
Loans held-for-sale	8,075		4,737
Other assets	952		3,494
Liabilities:
Other liabilities	3,657		6,788
Fair Value, Inputs, Level 3 [Member]
Assets:
Securities available-for-sale	13,833		14,092
Mortgage servicing rights	10,376		7,097
Fair Value, Inputs, Level 3 [Member] \| States and political subdivisions
Assets:
Securities available-for-sale	13,800	$ 4,600
Fair Value, Measurements, Recurring [Member]
Assets:
Loans held-for-sale	8,075		4,737
Mortgage servicing rights	10,376		7,097
Total financial assets	1,836,783		1,708,324
Liabilities:
Total	3,663		6,809
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member]
Assets:
Other assets	952		3,494
Liabilities:
Other liabilities	3,663		6,809
Fair Value, Measurements, Recurring [Member] \| Forward Contracts [Member]
Assets:
Other assets	930		508
Fair Value, Measurements, Recurring [Member] \| U.S. Treasury
Assets:
Securities available-for-sale	220,563		202,339
Fair Value, Measurements, Recurring [Member] \| U.S. government agencies
Assets:
Securities available-for-sale	59,036		61,888
Fair Value, Measurements, Recurring [Member] \| Mortgage Backed Securities, Issued by US Government Agencies
Assets:
Securities available-for-sale	153,148		172,302
Fair Value, Measurements, Recurring [Member] \| States and political subdivisions
Assets:
Securities available-for-sale	236,408		256,465
Fair Value, Measurements, Recurring [Member] \| Corporate bonds
Assets:
Securities available-for-sale	9,683		9,887
Fair Value, Measurements, Recurring [Member] \| Collateralized mortgage obligations
Assets:
Securities available-for-sale	696,513		672,967
Fair Value, Measurements, Recurring [Member] \| Asset-backed Securities
Assets:
Securities available-for-sale	274,941		236,877
Fair Value, Measurements, Recurring [Member] \| Collateralized loan obligations.
Assets:
Securities available-for-sale	166,158		79,763
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets:
Total financial assets	220,563		202,339
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| U.S. Treasury
Assets:
Securities available-for-sale	220,563		202,339
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets:
Loans held-for-sale	8,075		4,737
Total financial assets	1,592,011		1,484,796
Liabilities:
Total	3,663		6,809
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Assets:
Other assets	952		3,494
Liabilities:
Other liabilities	3,663		6,809
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Forward Contracts [Member]
Assets:
Other assets	930		508
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| U.S. government agencies
Assets:
Securities available-for-sale	59,036		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	153,148		172,302
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| States and political subdivisions
Assets:
Securities available-for-sale	222,575		242,373
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Corporate bonds
Assets:
Securities available-for-sale	9,683		9,887
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized mortgage obligations
Assets:
Securities available-for-sale	696,513		672,967
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Asset-backed Securities
Assets:
Securities available-for-sale	274,941		236,877
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized loan obligations.
Assets:
Securities available-for-sale	166,158		79,763
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets:
Mortgage servicing rights	10,376		7,097
Total financial assets	24,209		21,189
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| States and political subdivisions
Assets:
Securities available-for-sale	$ 13,833		$ 14,092