Goodwill and Other Intangible Assets - Narrative (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill impairment charge		$ 20.6		$ 20.6
Amortization expense for other intangible assets	$ 5.2		$ 5.8	$ 10.5	$ 12.2

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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