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Fair Value Measurements - Changes in Level 3 Liabilities (Details) - Level 3 - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Contingent Payment Obligations |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, beginning of period | $ 40.3 | $ 0.0
Purchases and issuances | 0.0 | 23.7
Settlements and reductions | 0.0 | 0.0
Net realized and unrealized (gains) losses | (19.3) | 16.6
Balance, end of period | 21.0 | 40.3
Net change in unrealized gains relating to instruments still held at the reporting date | (19.3) | 0.0
Affiliate Equity Purchase Obligations |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, beginning of period | 12.6 | 22.0
Purchases and issuances | 75.8 | 112.7
Settlements and reductions | (52.1) | (120.7)
Net realized and unrealized (gains) losses | (11.8) | (1.4)
Balance, end of period | 24.5 | 12.6
Net change in unrealized gains relating to instruments still held at the reporting date | $ (5.9) | $ 0.0

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- 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. + Details
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- Definition Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Purchases And Issuances + References No definition available. + Details
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- Definition Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Settlements And Reductions + References No definition available. + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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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. + References No definition available. + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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