Investment Securities (Amortized Cost and Fair Value of Available-for-Sale Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Security obligations due, amortized cost, One to five years	$ 340
Security obligations due, amortized cost, Five to ten years	18,735
Security obligations due, amortized cost, After ten years	132,528
Available for sale, amortized cost, total	151,603
Available for sale, amortized cost	370,609	$ 374,062
Security obligations due, Fair value, One to five years	345
Security obligations due, Fair value, Five to ten years	19,322
Security obligations due, Fair value, After ten years	136,090
Total Security obligations due, Fair value	155,757
Investment securities available for sale (carried at fair value)	373,937
Investment securities available for sale (carried at fair value)	373,937	370,875
Mortgage-backed securities, Government sponsored agencies
Schedule of Available-for-sale Securities [Line Items]
Available for sale, amortized cost	109,857	106,094
Investment securities available for sale (carried at fair value)	109,750	104,343
Collateralized mortgage obligations, Government sponsored agencies
Schedule of Available-for-sale Securities [Line Items]
Available for sale, amortized cost	109,149	110,994
Investment securities available for sale (carried at fair value)	$ 108,430	$ 109,281

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
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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 after the 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 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 after adjustments of available-for-sale debt securities at cost, maturing in the second through fifth 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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Fair value of investment in available-for-sale debt securities with a single maturity date.

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Amount of investment in available-for-sale debt securities with a single maturity date at cost, after adjustments, including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in the statement of income and fair value hedge accounting adjustments.

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

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