Fair Value Measurements - Fair Value Assets and Liabilities Measured on Recurring Basis (Detail) $ in Millions	Jun. 30, 2018 USD ($)
Assets:
Assets measured at fair value on a recurring basis	$ 10.2
Liabilities:
Liabilities measured at fair value on a recurring basis	49.5
Interest rate cap - derivative
Assets:
Assets measured at fair value on a recurring basis	9.4
Forward foreign currency contracts
Assets:
Assets measured at fair value on a recurring basis	0.8
Deferred compensation liabilities
Liabilities:
Liabilities measured at fair value on a recurring basis	49.5
Quoted Prices in Active Market for Identical Assets (Level 1)
Assets:
Assets measured at fair value on a recurring basis	0.0
Liabilities:
Liabilities measured at fair value on a recurring basis	49.5
Quoted Prices in Active Market for Identical Assets (Level 1) | Interest rate cap - derivative
Assets:
Assets measured at fair value on a recurring basis	0.0
Quoted Prices in Active Market for Identical Assets (Level 1) | Forward foreign currency contracts
Assets:
Assets measured at fair value on a recurring basis	0.0
Quoted Prices in Active Market for Identical Assets (Level 1) | Deferred compensation liabilities
Liabilities:
Liabilities measured at fair value on a recurring basis	49.5
Significant Other Observable Inputs (Level 2)
Assets:
Assets measured at fair value on a recurring basis	10.2
Liabilities:
Liabilities measured at fair value on a recurring basis	0.0
Significant Other Observable Inputs (Level 2) | Interest rate cap - derivative
Assets:
Assets measured at fair value on a recurring basis	9.4
Significant Other Observable Inputs (Level 2) | Forward foreign currency contracts
Assets:
Assets measured at fair value on a recurring basis	0.8
Significant Other Observable Inputs (Level 2) | Deferred compensation liabilities
Liabilities:
Liabilities measured at fair value on a recurring basis	0.0
Significant Unobservable Inputs (Level 3)
Assets:
Assets measured at fair value on a recurring basis	0.0
Liabilities:
Liabilities measured at fair value on a recurring basis	0.0
Significant Unobservable Inputs (Level 3) | Interest rate cap - derivative
Assets:
Assets measured at fair value on a recurring basis	0.0
Significant Unobservable Inputs (Level 3) | Forward foreign currency contracts
Assets:
Assets measured at fair value on a recurring basis	0.0
Significant Unobservable Inputs (Level 3) | Deferred compensation liabilities
Liabilities:
Liabilities measured at fair value on a recurring basis	$ 0.0