Fair Value Measurements (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments	$ 42.3	$ 44.9
Available-for-sale	2.4	2.2
Cost method investments	16.4	14.9
Equity method investment, other than temporary impairment	12.4	0.0
Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale	2.4	2.2
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value disclosure	43.5	0.0
Investments, fair value disclosure	113.1	74.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments	42.3	44.9
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale	2.4	2.2
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | SmartX
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investments	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Wealth Advisors
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investments	24.9	27.7
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value disclosure	0.0	0.0
Investments, fair value disclosure	0.0	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments	0.0	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale	0.0	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | SmartX
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investments	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Wealth Advisors
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investments	0.0	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value disclosure	0.0	0.0
Investments, fair value disclosure	24.7	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments	0.0	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale	0.0	0.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | SmartX
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investments	24.7
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Wealth Advisors
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investments	0.0	0.0
Estimate of Fair Value Measurement [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents, fair value disclosure	43.5	0.0
Investments, fair value disclosure	137.8	74.8
Estimate of Fair Value Measurement [Member] | Fair Value, Recurring [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investments	42.3	44.9
Estimate of Fair Value Measurement [Member] | Fair Value, Recurring [Member] | Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale	2.4	2.2
Estimate of Fair Value Measurement [Member] | Fair Value, Recurring [Member] | SmartX
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investments	24.7
Estimate of Fair Value Measurement [Member] | Fair Value, Recurring [Member] | Wealth Advisors
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cost method investments	$ 24.9	$ 27.7