Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Securities Available for Sale Alesco TPS Narratives (Details) (USD $)					9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2012 ALESCO Preferred Funding X, Ltd. [Member] Number_of_Underlying_Issuers	Dec. 31, 2011 ALESCO Preferred Funding X, Ltd. [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities	$ 311,083,000	$ 283,145,000			$ 1,276,000
Available-for-sale securities, gross unrealized losses	(4,224,000)	(4,721,000)			(2,919,000)
Accumulated other comprehensive income (loss), net of tax	2,204,000	654,000	852,000	(2,647,000)	1,109,000
Underlying issuers within the pool (number of issuers)					77
Assumed recoveries from defaulted issuers					0
Minimum Consolidated Assets for TPS Phase Out					$ 15,000,000,000
Prepayment Rate Assumption for TPS Phase Out, Year Two and Three					30.00%
Annual Prepayment Rate for TPS Phase Out, After Year Three					2.00%
Discount rate added to three month LIBOR for fair value analyais (percent)					14.00%	15.00%
Approximate lifetime average all-in discount rate (percent)					17.00%	18.00%
Discount rate added to three-month LIBOR for cash flow projections (percent)					1.25%	1.25%