Goodwill and Intangible Assets - Schedule of Intangible Assets and Goodwill (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Goodwill And Intangible Assets [Line Items]
Goodwill	$ 163,263	$ 158,743
Gross Carrying Amount	62,778	59,278
Accumulated Amortization	(34,000)	(27,735)
Net Carrying Amount	28,778	31,543
Core deposit intangibles
Goodwill And Intangible Assets [Line Items]
Gross Carrying Amount	43,578	43,578
Accumulated Amortization	(26,217)	(22,258)
Net Carrying Amount	17,361	21,320
Other intangible assets
Goodwill And Intangible Assets [Line Items]
Gross Carrying Amount	19,200	15,700
Accumulated Amortization	(7,783)	(5,477)
Net Carrying Amount	$ 11,417	$ 10,223