Goodwill and Other Amortizing Intangible Assets - Summarized Other Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	$ 24,856	$ 28,126
Accumulated Amortization	(13,223)	(13,100)
Net Intangible Assets	11,633	15,026
Customer deposit intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	22,573	25,843
Accumulated Amortization	(11,653)	(11,760)
Net Intangible Assets	10,920	14,083
Customer list intangible
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	2,283	2,283
Accumulated Amortization	(1,570)	(1,340)
Net Intangible Assets	$ 713	$ 943