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Fair Value Measurements - Changes in Level 3 Liabilities (Details) - Significant Unobservable Inputs (Level 3) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Contingent Payment Obligations
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 14.7	$ 21.0
Purchases and issuances	0.0	0.0
Settlements and reductions	0.0	0.0
Net realized and unrealized (gains) losses	(5.1)	1.9
Balance, end of period	9.6	22.9
Net change in unrealized gains relating to instruments still held at the reporting date	(5.1)	1.9
Affiliate Equity Purchase Obligations
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	53.9	24.5
Purchases and issuances	24.9	44.2
Settlements and reductions	(40.5)	(7.5)
Net realized and unrealized (gains) losses	(0.6)	(0.3)
Balance, end of period	37.7	60.9
Net change in unrealized gains relating to instruments still held at the reporting date	$ (0.6)	$ (0.3)

X

- Definition

Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included In Earnings And Other Comprehensive Income (Loss)

+ References

No definition available.

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Purchases And Issuances

+ References

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements And Reductions

+ References

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- Definition

Amount of unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-SubTopic 10
-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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