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Debt - 7.5% Notes Redemption (Details) - Long-term Debt [Member] - Senior secured notes due June 01, 2021 [Member]	12 Months Ended
	Dec. 31, 2017
Debt Instrument, Redemption [Line Items]
Redemptions rights after control change, percentage	101.00%
2018 [Member]
Debt Instrument, Redemption [Line Items]
Redemption price, percentage	101.875%
2019 and thereafter [Member]
Debt Instrument, Redemption [Line Items]
Redemption price, percentage	100.00%

X

- Definition

After a change of control, details of effect on note.

+ References

No definition available.

+ 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.

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X

- 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
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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