Segment Reporting - Financial Results by Reportable Segment Reconciled to Consolidated Income Before Income Taxes and Total Assets by Reportable Segment Reconciled to Consolidated Total Assets (Parenthetical) (Detail) (Operating Segments [Member], USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Servicing [Member]
Segment Reporting Information [Line Items]
Servicing revenue and fees	$ 4.7	$ 5.1	$ 9.6	$ 10.4
Asset Receivables Management [Member]
Segment Reporting Information [Line Items]
Servicing revenue and fees	$ 0.1	$ 0.2	$ 0.2	$ 0.3