Income Taxes, Unrecognized tax benefits (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Reconciliation of the gross amounts of unrecognized tax benefits
Unrecognized tax benefits as of January 1		$ 176.8	$ 174.2	$ 164.1
Gross increases for tax positions in prior periods		84.4	15.2	3.8
Gross increases for tax positions in current period		27.0	21.1	8.4
Settlements		0.0	(6.1)	(1.0)
Lapse of statute of limitations		(8.6)	(27.6)	(1.1)
Unrecognized tax benefits at the end of the period	$ 279.6	279.6	176.8	174.2
Estimated interest and penalties included in provision for income taxes		(3.8)	(4.2)	5.8
Tax-related interest and penalties liability for unrecognized tax benefits	36.9	36.9	37.7	$ 41.8
Amount for unrecognized tax benefits, including penalties and interest, which if recognized would impact the effective tax rate	311.7	311.7	$ 209.7
Unrecognized tax benefits, anticipated adjustment for changing facts and circumstances, over the next twelve month period	108.9	$ 108.9
Unrecognized tax benefit reserve	100.0
Minimum
Reconciliation of the gross amounts of unrecognized tax benefits
Unrecognized tax benefit reserve	100.0
Maximum
Reconciliation of the gross amounts of unrecognized tax benefits
Estimate of possible loss	$ 300.0