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Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)		3 Months Ended		9 Months Ended
	Aug. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Goodwill [Line Items]
Goodwill impairment	$ 0
Impairment charges				$ 0	$ 0
Amortization of other intangible assets		$ 2,779,000	$ 3,459,000	$ 8,763,000	$ 10,847,000
Core Deposits and Other Intangible Assets \| Minimum
Goodwill [Line Items]
Estimated useful lives of core deposits and customer relationships				5 years
Core Deposits and Other Intangible Assets \| Maximum
Goodwill [Line Items]
Estimated useful lives of core deposits and customer relationships				15 years