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

No definition available.

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- Definition

Represents the premium of par value in percent.

+ References

No definition available.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Balance Type:	debit
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- Definition

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

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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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-Subparagraph (SX 210.5-02.22(a)(1))
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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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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Balance Type:	na
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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

+ Details

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

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Long-term debt: Debt extinguishment, redemption and new debt issuances - $375 million 2022 Notes- (Details) - USD ($) $ in Thousands			1 Months Ended		12 Months Ended
	Mar. 12, 2015	Apr. 09, 2014	Dec. 31, 2016	Feb. 28, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016	Mar. 31, 2015	Aug. 19, 2013	Jan. 26, 2011
Debt extinguishment, redemption and new debt issuances
Losses on debt extinguishment and redemption						$ (587)	$ (10,144)
Debt premium					$ 1,239	1,105	171
2018 Notes
Debt extinguishment, redemption and new debt issuances
Redemption face amount	$ 240,000
Face amount									$ 240,000	$ 65,000	$ 175,000
Interest rate (as a percent)									8.375%	8.375%	8.375%
Repurchased amount including interest				$ 251,600
Principal amount plus accrued and unpaid interest (as a percent)	104.188%
Losses on debt extinguishment and redemption	$ (10,100)
Senior secured 2022 notes
Debt extinguishment, redemption and new debt issuances
Face amount			$ 125,000	$ 250,000		125,000
Interest rate (as a percent)				5.375%
Net proceeds			$ 124,300	$ 248,600
Premium of par value, in percent			100.375%
Offering costs						$ 1,202	$ 1,397
Debt premium			$ 500
Equity interest in foreign entities as collateral (in percent)					65.00%
Senior unsecured 2021 notes
Debt extinguishment, redemption and new debt issuances
Face amount		$ 200,000						$ 189,200
Interest rate (as a percent)		5.625%
Net proceeds		$ 195,800
Prior to December 1, 2021 \| Senior secured 2022 notes
Debt extinguishment, redemption and new debt issuances
Principal amount plus accrued and unpaid interest (as a percent)					100.00%
On or after December 1, 2021 \| Senior secured 2022 notes
Debt extinguishment, redemption and new debt issuances
Principal amount plus accrued and unpaid interest (as a percent)					100.00%