Securities - Contractual Maturities of Securities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Available-for-sale, Amortized Cost
Due in one year or less	$ 15,046
Due after one year through five years	42,062
Debt maturities, single maturity date, total	57,108
Available-for-sale, Amortized Cost	185,931	198,433
Available-for-sale, Fair Value
Due in one year or less	15,058
Due after one year through five years	41,986
Debt maturities, single maturity date, total	57,044
Available-for-sale Securities, Total	187,565us-gaap_AvailableForSaleSecurities	198,237us-gaap_AvailableForSaleSecurities
Held-to-maturity, Amortized Cost
Held-to-maturity, Amortized Cost	50,713us-gaap_HeldToMaturitySecurities	57,278us-gaap_HeldToMaturitySecurities
Held-to-maturity, Fair Value
Held-to-maturity, Fair Value	50,725	56,588
Proceeds from sale of securities
Proceeds from Sale of Available-for-sale Securities	19,179	6,736	39,236
Available-for-sale Securities, Gross Realized Gains		110
Available-for-sale Securities, Gross Realized Losses		103
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale, Amortized Cost
Debt maturities without single maturity date	128,823
Available-for-sale, Amortized Cost	100,002	121,042
Available-for-sale, Fair Value
Debt maturities without single maturity date	130,521
Available-for-sale Securities, Total	101,916	121,390
Held-to-maturity, Amortized Cost
Debt maturities without single maturity date	50,713
Held-to-maturity, Amortized Cost	16,823	16,788
Held-to-maturity, Fair Value
Debt maturities without single maturity date	50,725
Held-to-maturity, Fair Value	17,185	16,669
Collateralized Mortgage Backed Securities [Member]
Available-for-sale, Amortized Cost
Available-for-sale, Amortized Cost	28,821	32,223
Available-for-sale, Fair Value
Available-for-sale Securities, Total	28,605	31,736
Held-to-maturity, Amortized Cost
Held-to-maturity, Amortized Cost	33,890	40,490
Held-to-maturity, Fair Value
Held-to-maturity, Fair Value	$ 33,540	$ 39,919

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

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the next 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 available-for-sale debt securities at cost, net of adjustments, that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the cost over several maturity groupings. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings (less any cumulative-effect adjustments, as defined) and fair value hedge accounting adjustments.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount of held-to-maturity debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, over several maturity groupings.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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