Investment in Securities (Details 2) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Amortized Cost Due in 1 year or less	$ 18,898
Amortized Cost Due after 1 year through 5 years	62,453
Amortized Cost Due after 5 years through 10 years	180,082
Amortized Cost Due after 10 years	85,304
Amortized Cost Total	346,737
Fair Value Due in 1 year or less	19,036
Fair Value Due after 1 year through 5 years	66,994
Fair Value Due after 5 years through 10 years	190,378
Fair Value Due after 10 years	91,111
Fair Value Total	$ 367,519	$ 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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