Securities - Amortized Cost and Estimated Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 375,494	$ 337,774
Unrealized Gains	4,360	1,306
Unrealized Losses	659	6,427
Fair Value	379,195	332,653
U.S. Treasury
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	14,992
Unrealized Gains	0
Unrealized Losses	5
Fair Value	14,987
Federal agencies and GSEs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	126,829	137,070
Unrealized Gains	1,504	442
Unrealized Losses	219	3,473
Fair Value	128,114	134,039
Mortgage-backed and CMOs
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	182,732	113,883
Unrealized Gains	1,901	385
Unrealized Losses	393	2,401
Fair Value	184,240	111,867
State and municipal
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	41,427	80,022
Unrealized Gains	769	411
Unrealized Losses	42	531
Fair Value	42,154	79,902
Corporate
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,514	6,799
Unrealized Gains	186	68
Unrealized Losses	0	22
Fair Value	$ 9,700	$ 6,845

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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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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Amount 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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