Derivative Instruments Summary of Foreign Currency Derivative Contracts (Details) MXN in Millions, $ in Millions						4 Months Ended	7 Months Ended	9 Months Ended		12 Months Ended
		Jan. 17, 2017 USD ($)	Apr. 29, 2016 USD ($)	Jan. 15, 2016 USD ($)	Jan. 15, 2016 USD ($)	Apr. 25, 2017 USD ($)	Jul. 27, 2017 USD ($)	Sep. 30, 2017 USD ($) MXN / $	Sep. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)	Feb. 28, 2017 USD ($)	Jan. 17, 2017 MXN MXN / $	Jan. 17, 2017 USD ($) MXN / $	Apr. 29, 2016 MXN MXN / $	Apr. 29, 2016 USD ($) MXN / $	Jan. 15, 2016 MXN MXN / $	Jan. 15, 2016 USD ($) MXN / $
Derivative [Line Items]
Cash received/(paid) on settlement of foreign currency contracts								$ (14.4)	$ (58.4)
Not Designated as Hedging Instrument [Member] | Foreign Currency Forward Contracts [Member]
Derivative [Line Items]
Notional amount of foreign currency contracts												MXN 6,207.7	$ 340.0	MXN 1,057.3	$ 60.0	MXN 4,480.4	$ 300.0
Weighted-average exchange rate of foreign currency forward contracts | MXN / $												18.3	18.3	17.6	17.6	14.9	14.9
Maturity date of foreign currency contracts		Jan. 17, 2017	Apr. 29, 2016	Jan. 15, 2016
Not Designated as Hedging Instrument [Member] | Foreign Currency Forward Contracts [Member] | Foreign Exchange Gain (Loss) [Member]
Derivative [Line Items]
Cash received/(paid) on settlement of foreign currency contracts		$ (53.0)	$ 0.7	$ (49.0)
Not Designated as Hedging Instrument [Member] | Foreign Currency Forward Contracts [Member] | Offsetting Derivative Instrument [Member]
Derivative [Line Items]
Notional amount of foreign currency contracts												MXN 6,207.7	$ 287.0	MXN 1,057.3	$ 60.7	MXN 4,480.4	$ 251.0
Weighted-average exchange rate of foreign currency forward contracts | MXN / $												21.6	21.6	17.4	17.4	17.9	17.9
Maturity date of foreign currency contracts		Jan. 17, 2017	Apr. 29, 2016	Jan. 15, 2016
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing January 16, 2018 [Member]
Derivative [Line Items]
Notional amount of foreign currency contracts								$ 255.0
Maturity date of foreign currency contracts								Jan. 16, 2018
Notional amount of zero-cost collar contracts settled by the Company								$ 25.0			$ 115.0
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing January 16, 2018 [Member] | Call Option [Member]
Derivative [Line Items]
Weighted-average rate outstanding options | MXN / $								21.6
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing January 16, 2018 [Member] | Put Option [Member]
Derivative [Line Items]
Weighted-average rate outstanding options | MXN / $								24.7
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing January 16, 2018 [Member] | Foreign Exchange Gain (Loss) [Member]
Derivative [Line Items]
Cash received/(paid) on settlement of foreign currency contracts	[1]							$ 7.7
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing January 18, 2018 [Member]
Derivative [Line Items]
Notional amount of foreign currency contracts								$ 10.0
Maturity date of foreign currency contracts								Jan. 18, 2018
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing January 18, 2018 [Member] | Foreign Exchange Gain (Loss) [Member]
Derivative [Line Items]
Cash received/(paid) on settlement of foreign currency contracts								$ 0.4
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing July 27, 2017 [Member]
Derivative [Line Items]
Notional amount of foreign currency contracts							$ 70.0
Maturity date of foreign currency contracts							Jul. 27, 2017
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing July 27, 2017 [Member] | Foreign Exchange Gain (Loss) [Member]
Derivative [Line Items]
Cash received/(paid) on settlement of foreign currency contracts							$ 4.7
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing April 25, 2017 [Member]
Derivative [Line Items]
Notional amount of foreign currency contracts						$ 195.0
Maturity date of foreign currency contracts						Apr. 25, 2017
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing April 25, 2017 [Member] | Foreign Exchange Gain (Loss) [Member]
Derivative [Line Items]
Cash received/(paid) on settlement of foreign currency contracts						$ 25.8
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing January 15, 2016 [Member]
Derivative [Line Items]
Notional amount of foreign currency contracts										$ 80.0
Maturity date of foreign currency contracts										Jan. 15, 2016
Not Designated as Hedging Instrument [Member] | Foreign Currency Zero-Cost Collar Contracts [Member] | Zero-Cost Collar Contracts Maturing January 15, 2016 [Member] | Foreign Exchange Gain (Loss) [Member]
Derivative [Line Items]
Cash received/(paid) on settlement of foreign currency contracts					$ (10.1)

[1] During February and September 2017, the Company settled $115.0 million and $25.0 million, respectively, of the zero-cost collar contracts.