The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Intangible assets disclosure.

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Intangibles - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Intangible Assets Disclosure [Line Items]
Trade names	$ 626,600		$ 626,600		$ 582,800
Intangible assets, amortization expense	$ 65,960	$ 9,899	$ 93,402	$ 20,251
Trade Names
Intangible Assets Disclosure [Line Items]
Trade names, useful life			5 years
Backlog
Intangible Assets Disclosure [Line Items]
Intangible assets, weighted average useful life (years)			18 years
Patents
Intangible Assets Disclosure [Line Items]
Intangible assets, weighted average useful life (years)			10 years
Customer relationships
Intangible Assets Disclosure [Line Items]
Intangible assets, weighted average useful life (years)			18 years
Other Intangibles
Intangible Assets Disclosure [Line Items]
Intangible assets, weighted average useful life (years)			13 years