Investment Securities (Unrealized Gain (Loss) on Investments) (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Schedule of Investments [Line Items]
Available-for-sale debt securities, Amortized Cost	$ 117,211,000	$ 95,648,000
Available-for-sale debt securities, Unrealized Gains	5,000	14,000
Available-for-sale debt securities, Unrealized Losses	5,525,000	2,703,000
Available for sale debt securities, Fair Value	111,691,000	92,959,000
Held-to-maturity debt securities, Amortized Cost	153,321,000	101,356,000
Held-to-maturity debt securities, Unrealized Gains	61,000	41,000
Held-to-maturity debt securities, Unrealized Losses	3,366,000	914,000
Held-to-maturity debt securities, Fair Value	150,016,000	100,483,000
Available-for-sale securities and Held-to-maturity debt securities, Amortized Cost	270,532,000	197,554,000
Available-for-sale securities and Held-to-maturity debt securities, Unrealized Gains	66,000	55,000
Available-for-sale securities and Held-to-maturity debt securities, Unrealized Losses	8,891,000	3,661,000
Available-for-sale securities and Held-to-maturity debt securities, Fair Value	261,707,000	193,948,000
Available-for-sale equity securities, Amortized Cost		550,000
Available-for-sale equity securities, Unrealized Losses		44,000
Available for sale equity securities, Fair Value	492,000	506,000
U.S. Treasury and U.S. government agencies [Member]
Schedule of Investments [Line Items]
Available-for-sale debt securities, Amortized Cost	40,597,000	40,125,000
Available-for-sale debt securities, Unrealized Losses	2,257,000	1,395,000
Available for sale debt securities, Fair Value	38,340,000	38,730,000
Held-to-maturity debt securities, Amortized Cost	10,985,000	10,984,000
Held-to-maturity debt securities, Unrealized Losses	201,000	90,000
Held-to-maturity debt securities, Fair Value	10,784,000	10,894,000
Mortgage-backed U.S. Government Agencies [Member]
Schedule of Investments [Line Items]
Available-for-sale debt securities, Amortized Cost	43,713,000	26,398,000
Available-for-sale debt securities, Unrealized Gains	1,000	2,000
Available-for-sale debt securities, Unrealized Losses	1,288,000	569,000
Available for sale debt securities, Fair Value	42,426,000	25,831,000
Held-to-maturity debt securities, Amortized Cost	66,512,000	53,472,000
Held-to-maturity debt securities, Unrealized Gains	4,000
Held-to-maturity debt securities, Unrealized Losses	1,649,000	523,000
Held-to-maturity debt securities, Fair Value	64,867,000	52,949,000
State and political subdivision obligations [Member]
Schedule of Investments [Line Items]
Available-for-sale debt securities, Amortized Cost	31,551,000	27,775,000
Available-for-sale debt securities, Unrealized Gains	3,000	7,000
Available-for-sale debt securities, Unrealized Losses	1,980,000	739,000
Available for sale debt securities, Fair Value	29,574,000	27,043,000
Held-to-maturity debt securities, Amortized Cost	75,824,000	36,900,000
Held-to-maturity debt securities, Unrealized Gains	57,000	41,000
Held-to-maturity debt securities, Unrealized Losses	1,516,000	301,000
Held-to-maturity debt securities, Fair Value	74,365,000	36,640,000
Corporate debt securities [Member]
Schedule of Investments [Line Items]
Available-for-sale debt securities, Amortized Cost	1,350,000	1,350,000
Available-for-sale debt securities, Unrealized Gains	1,000	5,000
Available for sale debt securities, Fair Value	1,351,000	1,355,000
Equity Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale equity securities, Amortized Cost		550,000
Available-for-sale equity securities, Unrealized Losses		44,000
Available for sale equity securities, Fair Value	$ 492,000	$ 506,000

Available-for-sale securities and held-to-maturity amortized cost.

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Available-for-sale securities and held-to-maturity gross unrealized gain.

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Available-for-sale securities and held-to-maturity gross unrealized losses.

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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 before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale.

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