Segment Information - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014 Segment	Dec. 31, 2013
Segment Reporting, Asset Reconciling Item [Line Items]
Number of reportable segments	2
Assets	$ 3,722,086	$ 2,685,274
Portfolio Purchasing and Recovery [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	3,300,000
Tax Lien Transfer [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 386,100