Earnings Per Share - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2018	Jul. 01, 2017	Apr. 01, 2017	Dec. 30, 2017
Stockholders Equity Note [Line Items]
Option Indexed to Issuer's Equity, Strike Price		$ 162.11	$ 162.27
Equity Unit			$ 750.0
Preferred Stock, Liquidation Preference, Value			$ 750.0
Preferred Stock Conversion Rate Number Of Common Stock Shares		$ 6.1687	$ 6.1627
Document Period End Date		Mar. 31, 2018
Long-term Debt		$ 750.0
Common Stock, Par or Stated Value Per Share	$ 2.50	$ 2.50			$ 2.50
Equity Units Conversion Rate Number Of Common Stock Shares		0.7248	0.7241
Common Stock, Shares, Issued	176,902,738	176,902,738			176,902,738
Minimum [Member]
Stockholders Equity Note [Line Items]
Option Indexed to Issuer's Equity, Strike Price	$ 156.86	$ 162.11	$ 162.27
Maximum [Member]
Stockholders Equity Note [Line Items]
Option Indexed to Issuer's Equity, Strike Price	$ 203.92	$ 179.35	$ 179.53
Stock Options [Member]
Stockholders Equity Note [Line Items]
Antidilutive securities excluded from the computation of EPS		1,164,000		1,163,000