Securities - Amortized Cost and Estimated Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	$ 337,774
Unrealized Gains	1,306
Unrealized Losses	6,427
Securities available for sale, at fair value	332,653
Amortized Cost		$ 322,345
Unrealized Gains		2,620
Unrealized Losses		3,628
Fair Value		321,337
Federal agencies and GSEs
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	137,070
Unrealized Gains	442
Unrealized Losses	3,473
Securities available for sale, at fair value	134,039
Amortized Cost		114,246
Unrealized Gains		8
Unrealized Losses		2,127
Fair Value		112,127
Mortgage-backed and CMOs
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	113,883
Unrealized Gains	385
Unrealized Losses	2,401
Securities available for sale, at fair value	111,867
Amortized Cost		106,163
Unrealized Gains		293
Unrealized Losses		1,140
Fair Value		105,316
State and municipal
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	80,022
Unrealized Gains	411
Unrealized Losses	531
Securities available for sale, at fair value	79,902
Amortized Cost		92,711
Unrealized Gains		1,262
Unrealized Losses		347
Fair Value		93,626
Corporate
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	6,799
Unrealized Gains	68
Unrealized Losses	22
Securities available for sale, at fair value	$ 6,845
Amortized Cost		7,842
Unrealized Gains		234
Unrealized Losses		14
Fair Value		8,062
Equity securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost		1,383
Unrealized Gains		823
Unrealized Losses		0
Fair Value		$ 2,206

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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-Section 50
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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 before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as 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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