Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands		12 Months Ended
	Jan. 01, 2018 USD ($)	Dec. 31, 2018 USD ($) Segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Significant Accounting Policies [Line Items]
Number of reportable segments | Segment		2
Cash equivalent maturity period		three months or less
Interest rate cap hedges recognized in other comprehensive income, net of tax		$ 407	$ (242)	$ (305)
Loss on derivative		300
Production cost of contracts		11,679	11,204
Goodwill		136,057	117,435
Remaining performance obligation, amount		$ 722,800
Remaining performance obligation, percentage		70.00%
Tax Cuts And Jobs Act of 2017, deferred Income tax benefit		$ 13,000
Adoption of 2017 Tax Cuts and Jobs Act		$ 26
Minimum
Significant Accounting Policies [Line Items]
Estimated useful life of intangible assets (in years)		10 years
Income tax benefit percentage		50.00%
Maximum
Significant Accounting Policies [Line Items]
Estimated useful life of intangible assets (in years)		18 years
Structural Systems
Significant Accounting Policies [Line Items]
Goodwill		$ 18,622	0
Electronic Systems
Significant Accounting Policies [Line Items]
Goodwill		117,435	$ 117,435
Accounting Standards Update 2014-09
Significant Accounting Policies [Line Items]
Cumulative effect on retained earnings, net of tax	$ 8,700
Other Assets
Significant Accounting Policies [Line Items]
Interest rate cap hedge premium		300
Other Current Assets | Accounting Standards Update 2018-15
Significant Accounting Policies [Line Items]
Capitalized implementation costs		200
Accumulated Other Comprehensive Loss
Significant Accounting Policies [Line Items]
Adoption of 2017 Tax Cuts and Jobs Act		$ 1,318