Equity Arrangements - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended					6 Months Ended
	Mar. 31, 2018	Jun. 29, 2019	Sep. 29, 2018	Jun. 30, 2018	Jul. 01, 2017	Apr. 04, 2015	Jun. 29, 2019	Jun. 30, 2018	Dec. 29, 2018	May 17, 2017	May 11, 2017
Stockholders Equity Note [Line Items]
Treasury Stock, Shares, Acquired			2,086,792	1,399,732
Treasury Stock, Common, Value				$ 200.0				$ 200.0
Interest Expense					$ 1.3
Forward share purchase contract						$ 350.0
Payments for Repurchase of Common Stock		$ 1.1	$ 300.0	$ 201.3			$ 9.2	$ 212.7
Common Stock, Shares, Issued		176,902,738					176,902,738		176,902,738
Long-term Debt							$ 750.0
Number of common shares purchased under call option					4,600,000			3,200,000
Preferred Stock, Value, Issued		$ 750.0					$ 750.0		$ 750.0
Document Period End Date							Jun. 29, 2019
equity units issued					7,500,000
Equity Unit					$ 750.0
Shares Issued, Price Per Share		$ 137.59			$ 100		$ 137.59				$ 138.10
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share				$ 100	100		100
Preferred Stock, Liquidation Preference Per Share					1,000
Preferred Stock Conversion Rate Number Of Common Stock Shares					$ 6.1627		6.1859
equity unit proceeds					$ 726.0
Preferred Stock, Shares Issued					750,000
Preferred Stock, Liquidation Preference, Value					$ 750.0
Option Indexed to Issuer's Equity, Strike Price		$ 161.66			$ 162.27		$ 161.66
Forward Contract Indexed to Issuer's Equity, Shares					5,500,000	3,645,510
Forward Contract Indexed to Issuer's Equity, Indexed Shares		0.7268			0.7241		0.7268
Option Indexed to Issuer's Equity, Settlement Alternatives, Cash, at Fair Value		$ 35.5					$ 35.5
Percentage Of Contract Price Paid					5.375%
Forward Contract Indexed to Issuer's Equity, Settlement Alternatives, Cash, at Fair Value		39.2					$ 39.2			$ 117.1
Call Option [Member]
Stockholders Equity Note [Line Items]
Call option, average price (in dollars per share)					$ 5.43			$ 17.96
Maximum [Member]
Stockholders Equity Note [Line Items]
Option Indexed to Issuer's Equity, Strike Price	$ 203.92				179.53		$ 203.74
Minimum [Member]
Stockholders Equity Note [Line Items]
Option Indexed to Issuer's Equity, Strike Price	$ 156.86				$ 162.27		$ 156.72
May 2017 Capped Call [Member]
Stockholders Equity Note [Line Items]
Option Indexed to Issuer's Equity, Settlement Alternatives, Cash, at Fair Value		$ 19.5					$ 19.5
May 2017 Capped Call [Member] | Maximum [Member]
Stockholders Equity Note [Line Items]
Option Indexed to Issuer's Equity, Strike Price							$ 178.85
May 2017 Capped Call [Member] | Minimum [Member]
Stockholders Equity Note [Line Items]
Option Indexed to Issuer's Equity, Strike Price							$ 161.66
Call Option [Member]
Stockholders Equity Note [Line Items]
Adjustments to Additional Paid in Capital, Other					$ 25.1			$ 57.3