Income Taxes - Components of Net Loss for Income Tax (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Dec. 31, 2016	Dec. 31, 2017
Components Of Income Tax Expense Benefit Continuing Operations [Abstract]
U.S.	$ 11,082	$ 24,980
Non-U.S.	958	3,044
Loss before income taxes	$ 12,040	$ 28,024

No definition available.

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

+ Details

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- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

+ Details

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