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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Held-to-maturity [Abstract]
Held to maturity, Amortized Cost	$ 137,413	$ 157,206
Held-to-maturity, Fair Value	139,642	153,894
Held-to-maturity, Gross Unrealized Gains	2,378	210
Held-to-maturity, Gross Unrealized (Losses)	(149)	(3,522)
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	423,923	465,910
Available-for-sale, at fair value	432,260	462,464
Available-for-sale, Gross Unrealized Gains	8,748	1,748
Available-for-sale, Gross Unrealized (Losses)	(411)	(5,194)
Total investment securities, Amortized Cost	561,336	623,116
Total investment securities, Fair Value	571,902	616,358
Total investment securities, Gross Unrealized Gains	11,126	1,958
Total investment securities, Gross Unrealized (Losses)	(560)	(8,716)
MBS pass-through securities issued by FHLMC and FNMA
Debt Securities, Held-to-maturity [Abstract]
Held to maturity, Amortized Cost	80,451	88,606
Held-to-maturity, Fair Value	81,325	85,804
Held-to-maturity, Gross Unrealized Gains	1,018	7
Held-to-maturity, Gross Unrealized (Losses)	(144)	(2,809)
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	98,502	95,339
Available-for-sale, at fair value	100,071	94,467
Available-for-sale, Gross Unrealized Gains	1,617	358
Available-for-sale, Gross Unrealized (Losses)	(48)	(1,230)
SBA-backed securities
Debt Securities, Held-to-maturity [Abstract]
Held to maturity, Amortized Cost	7,999	8,720
Held-to-maturity, Fair Value	8,264	8,757
Held-to-maturity, Gross Unrealized Gains	265	37
Held-to-maturity, Gross Unrealized (Losses)	0	0
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	35,674	50,722
Available-for-sale, at fair value	36,286	50,781
Available-for-sale, Gross Unrealized Gains	688	465
Available-for-sale, Gross Unrealized (Losses)	(76)	(406)
CMOs issued by FNMA
Debt Securities, Held-to-maturity [Abstract]
Held to maturity, Amortized Cost	10,210	11,447
Held-to-maturity, Fair Value	10,492	11,327
Held-to-maturity, Gross Unrealized Gains	282	0
Held-to-maturity, Gross Unrealized (Losses)	0	(120)
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	22,702	28,275
Available-for-sale, at fair value	23,092	28,079
Available-for-sale, Gross Unrealized Gains	390	134
Available-for-sale, Gross Unrealized (Losses)	0	(330)
CMOs issued by FHLMC
Debt Securities, Held-to-maturity [Abstract]
Held to maturity, Amortized Cost	31,477	33,583
Held-to-maturity, Fair Value	32,157	33,021
Held-to-maturity, Gross Unrealized Gains	685	8
Held-to-maturity, Gross Unrealized (Losses)	(5)	(570)
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	139,398	145,979
Available-for-sale, at fair value	143,226	144,836
Available-for-sale, Gross Unrealized Gains	3,892	454
Available-for-sale, Gross Unrealized (Losses)	(64)	(1,597)
CMOs issued by GNMA
Debt Securities, Held-to-maturity [Abstract]
Held to maturity, Amortized Cost	3,763	3,739
Held-to-maturity, Fair Value	3,816	3,769
Held-to-maturity, Gross Unrealized Gains	53	30
Held-to-maturity, Gross Unrealized (Losses)	0	0
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	11,719	11,294
Available-for-sale, at fair value	11,755	11,021
Available-for-sale, Gross Unrealized Gains	42	1
Available-for-sale, Gross Unrealized (Losses)	(6)	(274)
Debentures of government- sponsored agencies
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	48,389	52,956
Available-for-sale, at fair value	49,046	53,018
Available-for-sale, Gross Unrealized Gains	727	185
Available-for-sale, Gross Unrealized (Losses)	(70)	(123)
Privately issued CMOs
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	0	295
Available-for-sale, at fair value	0	297
Available-for-sale, Gross Unrealized Gains	0	2
Available-for-sale, Gross Unrealized (Losses)	0	0
Obligations of state and political subdivisions
Debt Securities, Held-to-maturity [Abstract]
Held to maturity, Amortized Cost	3,513	11,111
Held-to-maturity, Fair Value	3,588	11,216
Held-to-maturity, Gross Unrealized Gains	75	128
Held-to-maturity, Gross Unrealized (Losses)	0	(23)
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	66,042	79,046
Available-for-sale, at fair value	67,282	77,960
Available-for-sale, Gross Unrealized Gains	1,386	134
Available-for-sale, Gross Unrealized (Losses)	(146)	(1,220)
Corporate bonds
Debt Securities, Available-for-sale [Abstract]
Available for Sale, Amortized Cost, Total	1,497	2,004
Available-for-sale, at fair value	1,502	2,005
Available-for-sale, Gross Unrealized Gains	6	15
Available-for-sale, Gross Unrealized (Losses)	$ (1)	$ (14)

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