Investments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Available-for-sale:
Available-for-sale	$ 2.4	$ 2.2
Held-to-maturity:
Held-to-maturity securities, current	3.6	4.0
Equity securities, Available-for-sale, Held-to-maturity, Fair Value	48.3	51.1
Equity securities, Available-for-sale, Held-to-maturity, Accumulated Gross Unrealized Loss, before Tax	0.2	0.1
Equity securities, Available-for-sale, Held-to-maturity, Accumulated Gross Unrealized Gain, before Tax	13.2	7.2
Equity investments, Available-for-sale, Held-to-maturity, Amortized Cost	35.3	44.0
Debt Securities, Available-for-sale, Realized Gain (Loss) [Abstract]
Equity Securities, FV-NI, Cost	29.1	37.7
Equity Securities, FV-NI, Current	42.3	44.9
Equity method investments	42.3	44.9
Equity Securities, FV-NI, Accumulated Gross Unrealized Gain, before Tax	13.2	7.2
Equity Securities, FV-NI, Accumulated Gross Unrealized Loss, before Tax	0.0	0.0
Equity securities, Available-for-sale, Realized gains	3.8	2.9	$ 1.0
Equity securities, Available-for-sale, Realized losses	0.0	0.0	3.1
Equity securities, Available-for-sale securities, Realized gains, net	3.8	2.9	$ (2.1)
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss	3.6	4.0
Debt Securities
Available-for-sale:
Available-for-sale securities, amortized cost basis	2.6	2.3
Available-for-sale securities, unrealized gain	0.0	0.0
Available-for-sale securities, unrealized loss	(0.2)	(0.1)
Available-for-sale	2.4	2.2
Certificates of deposit [Member]
Held-to-maturity:
Held-to-maturity securities, unrealized gain	0.0	0.0
Held-to-maturity securities, unrealized loss	0.0	0.0
Held-to-maturity securities, current	3.6	4.0
Debt Securities, Available-for-sale, Realized Gain (Loss) [Abstract]
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss	$ 3.6	$ 4.0