Significant Accounting Policies - Additional Information (Details) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Accounting Standards Update No. 2014-09
Significant Accounting Policies [Line Items]
Cumulative net earnings effect of new accounting standard on opening retained earnings	$ 3.8
Accounting Standards Update 2018-02
Significant Accounting Policies [Line Items]
Reduction in retained earnings due to adoption of the new accounting standard	$ 1.6
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%

Significant accounting policies.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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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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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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