Loss Per Share - Narrative (Details) - $ / shares shares in Thousands	6 Months Ended
Jun. 30, 2018	Aug. 31, 2017
5.25% Convertible Notes due December 30, 2019
Dilutive Earnings Per Share [Line Items]
Stated interest rate (as a percent)		5.25%
Second Lien Notes
Dilutive Earnings Per Share [Line Items]
Debt conversion price (in dollars per share)	$ 3.77
Outstanding common stock equivalents (in shares)	43,700

[Line Items] for Dilutive Earnings Per Share [Table]

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 40
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1930-109256

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-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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