Goodwill and other intangible assets - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization expense	$ 158,685	$ 149,974	$ 149,486
Trade names
Finite-Lived Intangible Assets [Line Items]
Indefinite lived intangible assets	$ 239,100

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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