Net deferred financing costs non current liability.

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Represents the number of major customers of the entity.

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- Definition

Significant accounting policies.

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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- Definition

Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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No definition available.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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No definition available.

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Significant Accounting Policies - Additional Information (Details) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) customer	Dec. 31, 2016 USD ($) customer	Dec. 31, 2015 customer
Significant Accounting Policies [Line Items]
Deferred financing costs recorded as a non-current asset		$ 3.1	$ 4.0
Net deferred financing costs recorded as a non-current liability		5.5	2.5
Allowance for doubtful accounts		$ 0.3	$ 0.4
Accounting Standards Update No. 2014-09 \| Scenario, Forecast
Significant Accounting Policies [Line Items]
Amount of revenue that the company expect to accelerate upon adoption of new accounting standard	$ 40.0
Net sales \| Customer concentration
Significant Accounting Policies [Line Items]
Number of major customers \| customer		2	2	2
Two customers and their related subcontractors \| Net sales \| Customer concentration
Significant Accounting Policies [Line Items]
Concentration percentage (as a percent)		69.00%	69.00%	66.00%
Minimum \| Building and improvements
Significant Accounting Policies [Line Items]
Useful life		10 years
Minimum \| Machinery and equipment
Significant Accounting Policies [Line Items]
Useful life		3 years
Minimum \| Software
Significant Accounting Policies [Line Items]
Finite lived intangible assets, useful life		3 years
Maximum \| Accounting Standards Update No. 2014-09 \| Scenario, Forecast
Significant Accounting Policies [Line Items]
Cumulative effect of new accounting standard on opening retained earnings	$ 4.0
Maximum \| Building and improvements
Significant Accounting Policies [Line Items]
Useful life		40 years
Maximum \| Machinery and equipment
Significant Accounting Policies [Line Items]
Useful life		25 years
Maximum \| Software
Significant Accounting Policies [Line Items]
Finite lived intangible assets, useful life		10 years
Aerospace Composites Malaysia Sdn. Bhd.
Significant Accounting Policies [Line Items]
Interest in affiliated company, accounted for using equity method of accounting (as a percent)		50.00%