Investment Securities Available for Sale (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	$ 30,428	$ 30,679
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	23,190	15,673
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	361,620	369,977
Available-for-sale Securities, Debt Securities	415,238	416,329
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.23%	0.23%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	3.16%	3.64%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	3.24%	3.33%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	3.01%	3.11%
Residential Mortgage Backed Securities [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	69,448	62,853
Available-for-sale Securities, Debt Securities	69,448	62,853
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.00%	0.00%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	2.44%	2.81%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	2.44%	2.81%
Commercial Mortgage Backed Securities [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	14,407	14,380
Available-for-sale Securities, Debt Securities	14,407	14,380
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.00%	0.00%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	3.86%	4.03%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	3.86%	4.03%
Municipal Bonds [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	17,575	15,673
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	113,472	113,502
Available-for-sale Securities, Debt Securities	131,047	129,175
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.00%	0.00%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	3.56%	3.64%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	4.60%	4.66%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	4.46%	4.53%
Residential [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	150,113	170,199
Available-for-sale Securities, Debt Securities	150,113	170,199
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.00%	0.00%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	2.61%	2.64%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	2.61%	2.64%
Commercial [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	5,615	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	14,180	9,043
Available-for-sale Securities, Debt Securities	19,795	9,043
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.00%	0.00%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	1.88%	0.00%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	2.35%	2.06%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	2.22%	2.06%
US Treasury Securities [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	30,428	30,679
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	0	0
Available-for-sale Securities, Debt Securities	$ 30,428	$ 30,679
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.23%	0.23%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	0.00%	0.00%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	0.23%	0.23%

Available for sale securities debt maturities after five through ten years weighted average yield.

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Available for sale securities debt maturities after ten years weighted average yield.

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Amount of available-for-sale debt securities at fair value maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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Amount of available-for-sale debt securities at fair value maturing after the tenth fiscal year following the latest fiscal year.

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

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