Debt - Debt and Equity Components and Issuance Costs of Convertible Notes (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Equity component	$ 60,511	$ 58,184
2017 Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Debt component	100,298
Equity component	14,702
Equity issuance cost	$ 788
Stated interest rate	3.00%
Effective interest rate	6.00%
2020 Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Debt component	$ 140,247
Equity component	32,253
Equity issuance cost	$ 1,106
Stated interest rate	3.00%
Effective interest rate	6.35%
2021 Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Debt component	$ 143,645
Equity component	17,355
Equity issuance cost	$ 581
Stated interest rate	2.875%
Effective interest rate	4.70%

Debt Instrument, Convertible, Carrying Amount of Debt Component

No definition available.

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Namespace Prefix:	ecpg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Balance Type:	debit
Period Type:	duration

- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031897-161870

+ Details

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

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.

+ Details

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- Details

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