Income Taxes - Deferred Tax Reclassifications (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Summary Of Deferred Tax Reclassifications [Line Items]
Other non-current assets	$ 519	$ 120
Deferred tax liability	(24,718)	(5,036)
Net deferred tax liability	(24,199)	(4,915)
Other Noncurrent Assets [Member]
Summary Of Deferred Tax Reclassifications [Line Items]
Other non-current assets	$ 519	$ 121

[Line Items] for Summary Of Deferred Tax Reclassifications [Table]

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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-Section 45
-Paragraph 6
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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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