Goodwill and Other Intangible Assets (Summary of the Gross Carrying Amount and Accumulated Amortization of Intangible Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Amortizable intangible assets:
Gross Carrying Amount	$ 48,039	$ 47,432
Accumulated Amortization	33,433	32,066
Unamortizable intangible assets:
Goodwill	239,272	239,272
Customer lists
Amortizable intangible assets:
Gross Carrying Amount	7,613	7,613
Accumulated Amortization	3,023	2,814
Core deposit intangibles
Amortizable intangible assets:
Gross Carrying Amount	28,440	28,440
Accumulated Amortization	24,500	23,832
SBA servicing asset
Amortizable intangible assets:
Gross Carrying Amount	10,583	9,976
Accumulated Amortization	4,658	4,188
Other
Amortizable intangible assets:
Gross Carrying Amount	1,403	1,403
Accumulated Amortization	$ 1,252	$ 1,232