Represents the amount deposited with the trustee for the benefit of the holders.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the percentage of redemption price of principal amount accrued interest.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of equity interest in the group's first tier foreign subsidiaries used as secure collateral.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Represents the period prior to the maturity of the debt instrument that the notes may be redeemed at a specified redemption price.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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Balance Type:	na
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Long-term debt: Debt extinguishment, redemption and new debt issuance- $250.0 million 2022 Notes (Details) - USD ($) $ in Thousands		1 Months Ended		3 Months Ended	12 Months Ended
	Mar. 12, 2015	Mar. 31, 2015	Feb. 28, 2015	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2013	Apr. 09, 2014	Aug. 19, 2013	Jan. 26, 2011
Debt extinguishment, redemption and new debt issuance- $250.0 million 2022 Notes
Amount of debt redeemed					$ 251,280
Loss on Debt extinguishment and redemption				$ (10,144)	10,144
Senior Secured 2022 Notes Member
Debt extinguishment, redemption and new debt issuance- $250.0 million 2022 Notes
Interest rate (as a percent)			5.375%
Aggregate principal amount of debt issued			$ 250,000
Proceeds from Issuance of Secured Debt					$ 248,603
Percentage of equity interest in foreign entities used as collateral					65.00%
Period prior to maturity date may be redeemed at specified price					3 months
Senior Secured 2022 Notes Member \| Cogent Finance
Debt extinguishment, redemption and new debt issuance- $250.0 million 2022 Notes
Aggregate principal amount of debt issued							$ 200,000
Senior Secured 2018 Notes Member
Debt extinguishment, redemption and new debt issuance- $250.0 million 2022 Notes
Amount of debt redeemed		$ 240,000
Interest rate (as a percent)		8.375%		8.375%				8.375%	8.375%
Amount deposited with the trustee for the benefit of the holders			$ 251,600
Aggregate principal amount of debt issued								$ 65,000	$ 175,000
Percentage of redemption price of principal amount accrued interest	104.188%
Proceeds from Issuance of Secured Debt						$ 69,882
Aggregate face value of debt repurchased	$ 240,000
Prior to December 1, 2021 \| Senior Secured 2022 Notes Member
Debt extinguishment, redemption and new debt issuance- $250.0 million 2022 Notes
Percentage of redemption price of principal amount accrued interest					100.00%
On or after December 1, 2021 \| Senior Secured 2022 Notes Member
Debt extinguishment, redemption and new debt issuance- $250.0 million 2022 Notes
Percentage of redemption price of principal amount accrued interest					100.00%