Securities (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Amortized cost
Due in one year or less, amortized cost
Due after one year through five years, amortized cost
Due after five years through ten years, amortized cost	53,140
Total amortized cost	422,960	454,060
Fair value
Due in one year or less, fair value
Due after one year through five years, fair value
Due after five years through ten years, fair value	54,123
Total fair value	431,040	459,598
Mortgage-backed GSE securities: residential [Member]
Amortized cost
Mortgage-backed GSE securities: residential, amortized cost	369,707
Total amortized cost	369,707	403,943
Fair value
Mortgage-related securities, fair value	376,641
Total fair value	$ 376,641	$ 408,535

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the second fiscal year through the fifth 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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Amount of available-for-sale debt securities at cost, net of adjustments, maturing in the next 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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