Income Taxes - Reconciliation to effective income tax rate (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Effective Income Tax Rate Reconciliation, Amount
U.S. statutory federal tax rate	$ 1,176.1
State and local income tax, net of federal income tax benefit (1)	17.6
Effect of cross-border tax laws	45.5
Effect of changes in tax laws or rates enacted in current period	0.0
Tax Credits	(19.3)
Changes in valuation allowances	0.0
Nontaxable or nondeductible items
Equity compensation	(205.9)
Other nontaxable or nondeductible items	13.2
Changes in unrecognized tax benefits	96.9
Provision for income taxes	$ 1,295.4	$ 570.3	$ 509.3
Income Taxes
U.S. statutory federal tax rate (as a percent)	21.00%	21.00%	21.00%
State and local income tax, net of federal income tax benefit (1)	0.30%	0.60%	0.60%
Federal statutory tax rate difference		1.90%	2.20%
Effect of cross-border tax laws	0.80%
Other		0.20%	0.30%
Effect of changes in tax laws or rates enacted in current period	0.00%
Tax Credits	(0.30%)
Changes in valuation allowances	0.00%
Nontaxable or nondeductible items
Equity compensation	(3.70%)
Other nontaxable or nondeductible items	0.20%
Changes in unrecognized tax benefits	1.70%
Effective tax rate (as a percent)	23.10%	18.90%	20.70%
United States
Effective Income Tax Rate Reconciliation, Amount
Other	$ (10.7)
Income Taxes
Other	(0.20%)
China
Effective Income Tax Rate Reconciliation, Amount
Federal statutory tax rate difference	$ 4.0
Effect of cross-border tax laws	151.6
Other	$ (43.7)
Income Taxes
Federal statutory tax rate difference	0.10%
Effect of cross-border tax laws	2.70%
Other	(0.80%)
Other foreign jurisdictions
Effective Income Tax Rate Reconciliation, Amount
Other	$ 70.1
Income Taxes
Other	1.30%