Business Combinations, Deconsolidation of Subsidiary, and Disposal Groups Held for Sale (Details 2) (Mexican Acquisition Partnerships, USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended
	Jul. 31, 2012 item	Dec. 31, 2011 item
Mexican Acquisition Partnerships
Divesture - Portfolio Asset Acquisition & Resolution Business Segment
Number of partnerships expected to be sold or otherwise disposed of		3
Period over which subsidiaries expected to be sold or disposed of		12 months
Number of wholly-owned subsidiaries		2
Number of subsidiaries sold	2
Proceeds from sale of interests in subsidiaries	$ 5.5
Gain recognized on the transaction	1.3
Recognition of previously-deferred income	0.5
Number of subsidiaries not sold	1
Portfolio assets held for investment	$ 0.7