Investment in Receivable Portfolios, Net - Summary of Accretable Yield and an Estimate of Zero Basis Future Cash Flows (Detail) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016
Investment in Receivables Portfolio [Roll Forward]
Balance at beginning of period	$ 3,412,753	$ 3,457,508	$ 3,177,980	$ 3,270,671	$ 3,457,508	$ 3,270,671
Revenue recognized, net	(272,236)	(251,970)	(267,452)	(270,094)	(524,206)	(537,546)
(Reductions) additions on existing portfolios, net	234,909	(32,692)	154,594	47,609
Additions for current purchases, net	258,687	200,728	183,217	193,654
Effect of foreign currency translation	66,174	39,179	(180,978)	(63,860)
Balance at end of period	3,700,287	3,412,753	3,067,361	3,177,980	3,700,287	3,067,361
Accretable Yield
Investment in Receivables Portfolio [Roll Forward]
Balance at beginning of period	3,029,588	3,092,004	2,977,955	3,047,640	3,092,004	3,047,640
Revenue recognized, net	(231,431)	(211,718)	(233,714)	(238,547)
(Reductions) additions on existing portfolios, net	225,021	(90,138)	59,459	39,538
Additions for current purchases, net	258,687	200,728	183,217	193,654
Effect of foreign currency translation	66,927	38,712	(181,223)	(64,330)
Balance at end of period	3,348,792	3,029,588	2,805,694	2,977,955	3,348,792	2,805,694
Estimate of Zero Basis Cash Flows
Investment in Receivables Portfolio [Roll Forward]
Balance at beginning of period	383,165	365,504	200,025	223,031	365,504	223,031
Revenue recognized, net	(40,805)	(40,252)	(33,738)	(31,547)	(81,100)	(65,300)
(Reductions) additions on existing portfolios, net	9,888	57,446	95,135	8,071
Additions for current purchases, net	0	0	0	0
Effect of foreign currency translation	(753)	467	245	470
Balance at end of period	$ 351,495	$ 383,165	$ 261,667	$ 200,025	$ 351,495	$ 261,667