Debt - Schedule of Debt Maturities (Parenthetical) (Detail) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Debt Instrument maturity year	2018
2017 Credit Agreement [Member]
Debt Instrument [Line Items]
Total borrowings due in 2022	$ 522.5

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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