Investment Securities, Available-for-sale Securities, Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Amortized Cost [Abstract]
Due in one year or less	$ 14,219
Due in one year through five years	121,037
Due after five years through ten years	5,009
Amortized Cost	523,894	$ 429,360
Fair Value [Abstract]
Due in one year or less	14,390
Due in one year through five years	120,669
Due after five years through ten years	4,979
Fair Value	527,587	439,071
Mortgage-Backed Securities and Collateralized Mortgage Obligations - Residential [Member]
Amortized Cost [Abstract]
Securities, amortized cost	344,892
Amortized Cost	344,892	308,432
Fair Value [Abstract]
Securities, fair value	348,317
Fair Value	348,317	316,158
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	38,737
Amortized Cost	38,737	40,955
Fair Value [Abstract]
Securities, fair value	39,232
Fair Value	$ 39,232	$ 42,217

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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