Investment Securities (Schedule of Investment Ratings) (Details) (USD $) In Thousands, unless otherwise specified			12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 ALESCO Preferred Funding VII [Member] Maximum [Member] item	Dec. 31, 2012 ALESCO Preferred Funding VII [Member] Minimum [Member] item
Schedule of Investments [Line Items]
Available-for-sale Securities, Amortized Cost Basis	$ 482,440	$ 417,939
Available-for-sale Securities, Gross Unrealized Gain (Loss)	16,316	6,714
Investment Securities Available-for-Sale: Fair Value	$ 496,815	$ 414,507
Number of banks currently performing			62	48

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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+ Details

- Definition

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.

+ References+ Details