Investment in Securities (Details 2) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Amortized Cost Due in 1 year or less	$ 9,303
Amortized Cost Due after 1 year through 5 years	55,153
Amortized Cost Due after 5 years through 10 years	138,102
Amortized Cost Due after 10 years	101,896
Amortized Cost Total	304,454
Fair Value Due in 1 year or less	9,404
Fair Value Due after 1 year through 5 years	59,392
Fair Value Due after 5 years through 10 years	146,603
Fair Value Due after 10 years	107,390
Fair Value Total	$ 322,789	$ 310,612

Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. 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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