Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Intangible Assets Goodwill And Other Assets [Line Items]
Goodwill	$ 1,100,000,000	$ 1,100,000,000
Other intangible assets	54,873,000	66,329,000
Amortization of core deposit and customer list intangible assets	11,500,000	$ 13,400,000	$ 10,100,000
Goodwill, impairment loss	$ 0
Minimum [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Intangible asset, useful life	10 years
Maximum [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Intangible asset, useful life	16 years