Segment Information - Reconciliation of Revenue and Operating Income from Segments to Consolidated (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	$ 287,796	$ 273,282	$ 863,815	$ 796,218
Depreciation and amortization	(8,235)	(6,933)	(24,669)	(19,879)
Other expense	(48,740)	(44,030)	(134,781)	(124,870)
(Loss) income before income taxes	(14,251)	40,292	72,748	106,227
Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	287,796	273,282	863,815	796,218
Operating income loss before depreciation and amortization	47,880	95,264	249,457	264,536
Operating Segments [Member] \| Portfolio Purchasing and Recovery [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	278,914	264,800	839,358	775,476
Operating income loss before depreciation and amortization	43,929	91,470	239,234	256,756
Operating Segments [Member] \| Tax Lien Transfer [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	8,882	8,482	24,457	20,742
Operating income loss before depreciation and amortization	3,951	3,794	10,223	7,780
Segment Reconciling Items [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation and amortization	(8,235)	(6,933)	(24,669)	(19,879)
Stock-based compensation	(5,156)	(4,009)	(17,259)	(13,560)
Other expense	(48,740)	(44,030)	(134,781)	(124,870)
(Loss) income before income taxes	$ (14,251)	$ 40,292	$ 72,748	$ 106,227

Operating Income (Loss) Before Depreciation and Amortization Stock Compensation and Other Expense

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

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-Name Staff Accounting Bulletin (SAB)

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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-Publisher FASB

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-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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-Publisher FASB

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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-Publisher FASB

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-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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