Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]

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Number Of Business Lines

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Revenue, performance obligation, contract term.

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Revenue, performance obligation, payment term.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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Amount of revenue recognized that was previously reported as deferred or unearned revenue.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Description of payment terms in contract with customer. Includes, but is not limited to, timing of payment, existence of financing component, variability of consideration and constraint on variable consideration.

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Description of timing for satisfying performance obligation in contract with customer. Includes, but is not limited to, as services are rendered, and upon shipment, delivery or completion of service.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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Business, Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2018 USD ($) Segments Business_Lines	Jun. 30, 2017 USD ($)	Jan. 01, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| Segments		2
Payment terms, description		The standard payment terms with customers is generally thirty to sixty days from the time of shipment, product delivery at the customer’s location or customer acceptance, depending on the terms of the related arrangement.
Contract duration, description		Substantially all of the Company’s contracts are one year or less in duration.
Restricted cash, cash and cash equivalents	$ 131,682	$ 131,682	$ 131,523		$ 128,575	$ 101,606
Restricted cash						18,251
Net cash (used in) provided by operating activities		21,752	(33,482)
Net cash (used in) provided by investing activities		(18,282)	(12,122)
Effect of exchange rates on cash, cash equivalents and restricted cash		3,107	29,917
Unbilled accounts receivable	35,857	35,857		$ 38,307
Inventories, net	(57,456)	(57,456)			(73,073)
Total stockholders' equity (deficit)	(33,793)	(33,793)	(70,490)		(39,637)	$ (72,114)
Amounts billed to customers	2,769	35,038
Deferred revenue	13,440	13,440			$ 8,335
Deferred revenue recognized	136	$ 1,222
Minimum [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Payment terms		30 days
Maximum [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Payment terms		60 days
Contract duration		1 year
ASU 2016-18 [Member] \| Restatement Adjustment [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Restricted cash, cash and cash equivalents			18,251
Net cash (used in) provided by operating activities			(1,809)
Net cash (used in) provided by investing activities			(17,625)
Effect of exchange rates on cash, cash equivalents and restricted cash			$ 1,183
Accounting Standards Update 2014-09 [Member] \| Adjustments [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Unbilled accounts receivable	35,857	$ 35,857		38,307
Inventories, net	26,659	26,659		29,823
Total stockholders' equity (deficit)	$ 9,198	$ 9,198		$ 8,484
Standard Products Group [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of business lines \| Business_Lines		2