Acquisitions - Cummins-American Corp. (Details) $ / shares in Units, $ in Thousands			6 Months Ended
	May 31, 2021 USD ($) $ / shares	May 28, 2021 USD ($) $ / shares	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Consideration paid
Goodwill			$ 317,873	$ 317,873
CAC
Merger agreement
Share consideration conversion ratio	444.4783
Per share cash consideration entitled (in dollars per share) | $ / shares	$ 14,173.96
Additional consideration paid in the form of a special dividend payment to CAC shareholders | $ / shares		$ 12,087.58
Special cash dividend		$ 60,000
Pre-tax acquisition expenses			800
Assets acquired:
Cash and cash equivalents	$ 298,637
Securities	702,367
Portfolio loans, net of ACL	430,470
Premises and equipment	17,034
Other intangible assets	17,340
Mortgage servicing rights	629
Other assets	8,176
Total assets acquired	1,474,653
Liabilities assumed:
Deposits	1,315,671
Other borrowings	16,651
Other liabilities	19,205
Total liabilities assumed	1,351,527
Net assets acquired	123,126
Consideration paid
Cash	70,358
Common stock	59,105
Total consideration paid	129,463
Goodwill	6,337		$ 6,300
Fair value of PCD financial assets	60,500
Gross contractual amounts receivable relating to the PCD financial assets	65,200
Contractual cash flows specific to the PCD financial assets will not be collected	$ 4,200