Share-based Compensation (Schedule of Status of Stock Option Plans) (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of period, Number of shares | shares	3.6
Outstanding at beginning of period, Weighted Average Exercise Price | $ / shares	$ 119.68
Granted, Number of shares | shares	0.0
Granted, Weighted Average Exercise Price | $ / shares	$ 0
Exercised, Number of shares | shares	(0.3)
Exercised, Weighted Average Exercise Price | $ / shares	$ 67.87
Forfeited and cancelled, Number of shares | shares	(0.3)
Forfeited and cancelled, Weighted Average Exercise Price | $ / shares	$ 158.71
Outstanding at end of period, Number of shares | shares	3.0
Outstanding at end of period, Weighted Average Exercise Price | $ / shares	$ 119.51
Outstanding at end of period, Weighted Average Remaining Contractual Term (in years)	4 years 29 days
Outstanding at end of period, Aggregate Intrinsic Value | $	$ 49.0
Vested and unvested expected to vest at end of period, Number of shares | shares	3.0
Vested and unvested expected to vest at end of period, Weighted Average Exercise Price | $ / shares	$ 119.49
Vested and unvested expected to vest at end of period, Weighted Average Remaining Contractual Term (in years)	4 years 25 days
Vested and unvested expected to vest at end of period, Aggregate Intrinsic Value | $	$ 49.0
Exercisable at end of period, Number of shares | shares	2.9
Exercisable at end of period, Weighted Average Exercise Price | $ / shares	$ 119.15
Exercisable at end of period, Weighted Average Remaining Contractual Term (in years)	3 years 11 months 4 days
Exercisable at end of period, Aggregate Intrinsic Value | $	$ 48.9