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Significant Accounting Policies - Additional Information (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 USD ($) Segment Facility | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Significant Accounting Policies [Line Items] |  |  |
Number of reportable segments | Segment | 3 |  |
Number of manufacturing facilities | Facility | 44 |  |
Income tax expense | $ 6,800 |  |
Net profit change on contracts | 163,052 | $ 6,663 | $ (6,486)
Cash paid for debt prepayment | $ 31,600 |  |
Maturity period of highly liquid investments | Three months or less |  |
Land and Buildings [Member] | Minimum [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives | 15 years |  |
Land and Buildings [Member] | Maximum [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives | 40 years |  |
Machinery and Equipment [Member] | Minimum [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives | 3 years |  |
Machinery and Equipment [Member] | Maximum [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives | 12 years |  |
Joint Venture [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Investment in joint venture | 49.00% |  |
ASU 2016-09 [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Reclassification of tax benefits from deferred taxes to retained earnings | $ 700 |  |
Accounting Standards Update 2014-09 [Member] | Maximum [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Net profit change on contracts | $ 100 |  |

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- Definition Amount of income tax expense from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act of 2017. + References No definition available. + Details
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- Definition Amount of the cumulative effect on retained earnings net of related income tax effect. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794 + Details
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