Stock-Based Compensation, Option Plans (Details) - Stock Options - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Stock-Based Compensation
Total intrinsic value of stock options exercised (in dollars)	$ 437.1	$ 190.7	$ 1,338.8	$ 652.3
Total fair value of stock options vested (in dollars)	0.9	$ 0.9	113.8	$ 98.8
Total compensation cost related to non-vested options not yet recognized (in dollars)	$ 385.0		$ 385.0
Weighted average expected amortization period			3 years 7 months 20 days