Business Combinations - Components of Purchase Price Allocation for Acquisition/Merger (Detail)			3 Months Ended	0 Months Ended	3 Months Ended	0 Months Ended		3 Months Ended
	Mar. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Mar. 31, 2014 Cabot Acquisition [Member] USD ($)	Jun. 13, 2013 AACC Merger [Member] USD ($)	Mar. 31, 2014 AACC Merger [Member] USD ($)	Feb. 07, 2014 Marlin [Member] USD ($)	Feb. 07, 2014 Marlin [Member] GBP (£)	Mar. 31, 2014 Marlin [Member] USD ($)
Business Acquisition [Line Items]
Cash paid at acquisition			$ 177,246,000	$ 150,800,000	$ 316,485,000	$ 274,068,000	£ 166,800,000
Cash consideration used to repay Acquiree loans						73,700,000	44,800,000
Stock consideration					62,352,000
Liabilities assumed						246,500,000	150,000,000
Business combination, acquisition and integration costs								9,800,000
Allocation of purchase price:
Cash			57,520,000		23,156,000	16,342,000
Investment in receivable portfolios			558,951,000		383,382,000	208,450,000
Deferred court costs					6,940,000	914,000
Property and equipment			13,672,000		11,003,000	1,508,000
Other assets			20,349,000		16,004,000	18,091,000
Preferred equity certificates assumed			(211,549,000)
Liabilities assumed					(126,059,000)	(301,180,000)
Debt assumed			(559,907,000)
Other liabilities assumed			(45,142,000)
Redeemable noncontrolling interests			(12,064,000)
Noncontrolling interests			(4,051,000)
Identifiable intangible assets			7,559,000		1,470,000
Goodwill	844,567,000	504,213,000	351,908,000		62,941,000	329,943,000
Total net assets acquired			$ 177,246,000		$ 378,837,000	$ 274,068,000