Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 403,001	$ 407,276	$ 403,001
Gross Unrealized Gains	4,491	2,231
Gross Unrealized Losses	(3,722)	(7,317)
Fair Value	403,770	402,190
Corporate bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	1,206	1,206
Gross Unrealized Gains	4	0
Gross Unrealized Losses	(7)	(18)
Fair Value	1,203	1,188
Small Business Administration
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	11,936	12,292
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(245)	(362)
Fair Value	11,691	11,930
U.S. Treasury and U.S. government sponsored entities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	5,911	6,111
Gross Unrealized Gains	4	0
Gross Unrealized Losses	(68)	(102)
Fair Value	5,847	6,009
State and political subdivisions
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	211,197	211,762
Gross Unrealized Gains	4,080	2,075
Gross Unrealized Losses	(541)	(1,893)
Fair Value	214,736	211,944
Mortgage-backed securities - residential
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	151,555	154,130
Gross Unrealized Gains	241	84
Gross Unrealized Losses	(2,188)	(4,167)
Fair Value	149,608	150,047
Collateralized mortgage obligations - residential
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	21,196	21,775
Gross Unrealized Gains	162	72
Gross Unrealized Losses	(673)	(775)
Fair Value	$ 20,685	$ 21,072

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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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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