Investment Securities (Amortized Cost and Fair Value of Available-for-Sale Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Security obligations due, amortized cost, within one year	$ 160
Security obligations due, amortized cost, One to five years	5,001
Security obligations due, amortized cost, Five to ten years	24,044
Security obligations due, amortized cost, After ten years	90,821
Available for sale, amortized cost, total	120,026
Available for sale, amortized cost	276,849	$ 251,788
Security obligations due, Fair Value, within one year	158
Security obligations due, Fair value, One to five years	5,034
Security obligations due, Fair value, Five to ten years	25,175
Security obligations due, Fair value, After ten years	91,963
Total Security obligations due, Fair value	122,330
Investment securities available for sale (carried at fair value)	277,378	249,913
Mortgage-backed securities, Government sponsored agencies
Schedule of Available-for-sale Securities [Line Items]
Available for sale, amortized cost	68,335	92,871
Investment securities available for sale (carried at fair value)	67,798	92,517
Collateralized mortgage obligations, Government sponsored agencies
Schedule of Available-for-sale Securities [Line Items]
Available for sale, amortized cost	88,488	68,621
Investment securities available for sale (carried at fair value)	$ 87,250	$ 68,047

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 25
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Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth through tenth rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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