Share-Based Compensation Plans - Terms and Assumptions (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
TSR PSU
Weighted-average assumptions used to estimate fair value:
Expected dividend yield	0.80%	0.70%	0.80%
Expected stock price volatility	48.90%	29.60%	30.80%
Risk-free interest rate	0.20%	1.40%	2.50%
Contractual term in years	2 years 10 months 24 days	2 years 10 months 24 days	2 years 9 months 18 days
Weighted-average fair value estimate at grant date	$ 2.7	$ 3.6	$ 3.0
Weighted-average fair value estimate per share (in dollars per share)	$ 103.83	$ 94.53	$ 105.16
Time Based Vesting Option
Weighted-average assumptions used to estimate fair value:
Expected dividend yield		0.70%	0.80%
Expected stock price volatility		29.70%	30.30%
Risk-free interest rate		1.30%	2.50%
Contractual term in years	4 years 6 months	4 years 6 months	4 years 6 months
Weighted-average fair value estimate at grant date		$ 1.7	$ 3.0
Weighted-average fair value estimate per share (in dollars per share)		$ 21.10	$ 21.58