Shareholders' Equity and Noncontrolling Interests, Stock Repurchase (Details) - USD ($) shares in Millions, $ in Millions				3 Months Ended	14 Months Ended
	Apr. 30, 2018	Apr. 24, 2018	Jan. 24, 2017	Mar. 31, 2018	Mar. 31, 2018
2017 Stock Repurchase Program
Shareholders' Equity
Value of shares authorized to be repurchased			$ 1,000.0
Repurchase of stock program, period			2 years
Number of shares repurchased and retired				4.2	12.6
Payments for shares repurchased and retired (in dollars)				$ 382.0	$ 1,000.0
2018 Stock Repurchase Program
Shareholders' Equity
Value of shares authorized to be repurchased		$ 2,000.0
Repurchase of stock program, period		3 years
Number of shares repurchased	0.7
Payments for shares repurchased (in dollars)	$ 55.5