Goodwill and Other Intangible Assets - Summary of the Gross Carrying Amount and Accumulated Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Amortizable intangible assets:
Gross Carrying Amount	$ 47,432	$ 43,532
Accumulated Amortization	32,066	26,315
Unamortizable intangible assets:
Goodwill	239,272	234,368
Customer lists
Amortizable intangible assets:
Gross Carrying Amount	7,613	6,013
Accumulated Amortization	2,814	2,185
Core deposit intangibles
Amortizable intangible assets:
Gross Carrying Amount	28,440	28,440
Accumulated Amortization	23,832	20,610
SBA servicing asset
Amortizable intangible assets:
Gross Carrying Amount	9,976	7,776
Accumulated Amortization	4,188	2,393
Other
Amortizable intangible assets:
Gross Carrying Amount	1,403	1,303
Accumulated Amortization	$ 1,232	$ 1,127