Stock-Based Compensation, Stock Option Activity (Details) - Stock Options - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Stock option activity
Options outstanding at the beginning of the period (in shares)	67,985,648
Non-vested options, options granted (in shares)	215,080
Options exercised (in shares)	(757,598)
Options forfeited (in shares)	(31,160)
Options outstanding at the end of the period (in shares)	67,411,970	67,985,648
Vested and non-vested options expected to vest at the end of the period (in shares)	64,076,188
Exercisable at the end of the period (in shares)	30,329,950
Weighted Average Exercise Price
Weighted average exercise price, options outstanding at the beginning of the period (in dollars per share)	$ 37.58
Weighted average exercise price, options granted (in dollars per share)	64.69
Weighted average exercise price, options exercised (in dollars per share)	28.12
Weighted average exercise price, options forfeited (in dollars per share)	42.37
Weighted average exercise price, options outstanding at the end of the period (in dollars per share)	37.77	$ 37.58
Weighted average exercise price, vested and non-vested options expected to vest (in dollars per share)	37.47
Weighted average exercise price, exercisable (in dollars per share)	$ 31.94
Weighted Average Remaining Contractual Term
Weighted average remaining contractual term of options outstanding	6 years 6 months 25 days	6 years 9 months 14 days
Weighted average remaining contractual term of options vested options and non-vested expected to vest	6 years 6 months
Weighted average remaining contractual term of options exercisable	5 years 1 month 6 days
Aggregate Intrinsic Value
Aggregate intrinsic value of options outstanding	$ 1,901.0	$ 1,890.4
Aggregate intrinsic value of options, vested and non-vested options expected to vest	1,826.2
Aggregate intrinsic value of options exercisable	$ 1,032.0