Investment Securities, Available-for-sale Securities, Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Amortized Cost [Abstract]
Due in one year or less	$ 15,667
Due in one year through five years	90,946
Due after five years through ten years	9
Amortized Cost	430,780	$ 429,360
Fair Value [Abstract]
Due in one year or less	15,954
Due in one year through five years	90,435
Due after five years through ten years	9
Fair Value	434,552	439,071
Mortgage-Backed Securities and Collateralized Mortgage Obligations - Residential [Member]
Amortized Cost [Abstract]
Securities, amortized cost	290,508
Amortized Cost	290,508	308,432
Fair Value [Abstract]
Securities, fair value	293,585
Fair Value	293,585	316,158
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	33,650
Amortized Cost	33,650	40,955
Fair Value [Abstract]
Securities, fair value	34,569
Fair Value	$ 34,569	$ 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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