Accumulated Other Comprehensive Income (Loss) - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Equity [Abstract]
Amounts reclassified out of accumulated other comprehensive income related to defined benefit pension plans as component of net periodic benefit cost, actuarial net gain or loss	$ 0.3	$ 0.5

Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration