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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, 2021 | Dec. 31, 2020
Affiliate Equity Purchase Obligations |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, beginning of period | $ 22.0 | $ 19.8
Net realized and unrealized (gains) losses | (1.4) | (4.3)
Purchases and issuances | 112.7 | 310.6
Settlements and reductions | (120.7) | (304.1)
Balance, end of period | 12.6 | 22.0
Net change in unrealized (gains) losses relating to instruments still held at the reporting date | 0.0 | 0.0
Contingent Payment Obligations |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, beginning of period | 0.0 | 0.0
Net realized and unrealized (gains) losses | 16.6 | 0.0
Purchases and issuances | 23.7 | 0.0
Settlements and reductions | 0.0 | 0.0
Balance, end of period | 40.3 | 0.0
Net change in unrealized (gains) losses relating to instruments still held at the reporting date | $ 0.0 | $ 0.0

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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 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 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 http://asc.fasb.org/extlink&oid=123874694&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 http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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