Investment Securities Available for Sale (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	$ 30,679	$ 4,010
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	27,510
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	15,673	2,450
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	369,977	295,077
Available-for-sale Securities, Debt Securities	416,329	329,047
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%	0.24%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	3.64%	2.95%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	3.33%	3.02%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	3.11%	2.75%
Residential Mortgage Backed Securities [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	0
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	62,853
Available-for-sale Securities, Debt Securities	62,853
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.00%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	0.00%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	2.81%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	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	14,380	14,483
Available-for-sale Securities, Debt Securities	14,380	14,483
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	4.03%	3.23%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	4.03%	3.23%
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	15,673	2,450
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	113,502	47,134
Available-for-sale Securities, Debt Securities	129,175	49,584
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	3.64%	2.95%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	4.66%	4.65%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	4.53%	4.56%
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	170,199	223,390
Available-for-sale Securities, Debt Securities	170,199	223,390
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	2.64%	2.70%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	2.64%	2.70%
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	0	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	9,043	10,070
Available-for-sale Securities, Debt Securities	9,043	10,070
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	2.06%	2.06%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	2.06%	2.06%
U.S. Government Agency Securities [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	0
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	0
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	0
Available-for-sale Securities, Debt Securities	0
Available for Sale Securities Debt Maturities with in One Year Weighted Average Yield	0.00%
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Weighted Average Yield	0.00%
Available for Sale Securities Debt Maturities After Five Through Ten Years Weighted Average Yield	0.00%
Available for Sale Securities Debt Maturities After Ten Years Weighted Average Yield	0.00%
Available for Sale Securities Debt Maturities Without Single Maturity Date Weighted Average Yield	0.00%
US Treasury Securities [Member]
Mortgage Backed and Collateral Mortgage Obligation
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	30,679	4,010
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	0	27,510
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	$ 30,679	$ 31,520
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%	0.24%
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%	0.24%

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

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Available-for-sale securities debt maturities year two through five fair value

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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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