Schedule II - Valuation and Qualifying Account (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 14,337	$ 2,528	$ 2,477
Additions / Charged to Expense	346	10,374	570
Deductions	(9,725)	(761)	(751)
Other	(181)	2,196	232
Balance at end of period	4,777	14,337	2,528
Allowance for excess and obsolete inventory
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	4,626	2,200	5,005
Additions / Charged to Expense	19,727	1,762	1,312
Deductions	(2,769)	(1,855)	(703)
Other	0	2,519	(3,414)
Balance at end of period	21,584	4,626	2,200
Allowance for deferred tax assets
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	5,442	2,798	0
Additions / Charged to Expense	53,399	2,644	2,798
Deductions	(1,125)	0	0
Other	0	0	0
Balance at end of period	$ 57,716	$ 5,442	$ 2,798

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

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