Equity, Option Plans (Details) - Stock Options - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock-Based Compensation
Total intrinsic value of stock options exercised (in dollars)	$ 329.6	$ 188.1	$ 268.7
Total fair value of stock options vested (in dollars)	57.3	$ 51.0	$ 46.3
Total compensation cost related to non-vested options not yet recognized (in dollars)	$ 152.2
Weighted average expected amortization period	3 years 4 months 9 days