Premises, Equipment and Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Premises and Equipment [Abstract]
Premises and equipment before accumulated depreciation	$ 184,361	$ 180,197
Accumulated depreciation	112,268	105,991
Total premises and equipment	72,093	74,206
Operating lease ROU assets	$ 23,300	$ 26,400
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets	Other Assets
Net Lease Cost [Abstract]
Operating lease cost	$ 7,176	$ 7,382
Variable lease cost	2,090	2,141
Short-term lease cost	369	453
Sublease income	(466)	(502)
Total premises and equipment	9,169	9,474
Future Minimum Rental Commitments Related to Non-cancelable Operating Leases [Abstract]
2022	6,543
2023	5,440
2024	4,696
2025	3,499
2026	2,609
Thereafter	7,985
Total lease payments	30,772
Less: interest	(3,171)
Present value of lease liabilities	$ 27,601	$ 32,800
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Other Liabilities	Other Liabilities
Additional Information Related to Operating Leases [Abstract]
Weighted average remaining lease term, in years	6 years 10 months 28 days	7 years 2 months 15 days
Weighted average discount rate	2.97%	3.02%
Cash paid for amounts included in the measurement of lease liabilities [Abstract]
Operating cash flows from operating leases	$ 7,373	$ 7,934
ROU assets obtained in exchange for lease liabilities	1,843	3,441
Rental expense	7,200	8,000	$ 8,000
Land, Buildings and Improvements [Member]
Premises and Equipment [Abstract]
Premises and equipment before accumulated depreciation	125,320	125,002
Furniture and Equipment [Member]
Premises and Equipment [Abstract]
Premises and equipment before accumulated depreciation	$ 59,041	$ 55,195
Furniture and Equipment [Member] \| Minimum [Member]
Premises and Equipment [Abstract]
Property, plant and equipment, useful life	3 years
Furniture and Equipment [Member] \| Maximum [Member]
Premises and Equipment [Abstract]
Property, plant and equipment, useful life	10 years
Building and Improvements [Member] \| Minimum [Member]
Premises and Equipment [Abstract]
Property, plant and equipment, useful life	5 years
Building and Improvements [Member] \| Maximum [Member]
Premises and Equipment [Abstract]
Property, plant and equipment, useful life	20 years

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