Investment in Receivable Portfolios, Net - Summary of Accretable Yield and an Estimate of Zero Basis Future Cash Flows (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Investment in Receivables Portfolio [Roll Forward]
Balance at beginning of period	$ 2,399,936		$ 1,002,310
Revenue recognized, net	(237,568)	(140,683)
Net additions on existing portfolios	100,880	180,695
Additions for current purchases	591,205	66,808
Balance at end of period	2,854,453	1,109,130	1,002,310
Accretable Yield [Member]
Investment in Receivables Portfolio [Roll Forward]
Balance at beginning of period	2,391,471		984,944
Revenue recognized, net	(231,057)	(135,072)
Net additions on existing portfolios	92,325	173,634
Additions for current purchases	591,205	66,808
Balance at end of period	2,843,944	1,090,314	984,944
Estimate of Zero Basis Cash Flows [Member]
Investment in Receivables Portfolio [Roll Forward]
Balance at beginning of period	8,465		17,366
Revenue recognized, net	(6,511)	(5,611)
Net additions on existing portfolios	8,555	7,061
Additions for current purchases	0	0
Balance at end of period	$ 10,509	$ 18,816	$ 17,366