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Fair Value Measurements - Changes in Level 3 Liabilities (Details) - Significant Unobservable Inputs (Level 3) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Contingent payment obligations |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | $ 31.4 | $ 0.0 | $ 40.3 | $ 0.0
Net realized and unrealized losses (gains) | (17.2) | 0.0 | (26.1) | 0.0
Purchases and issuances | 0.0 | 0.0 | 0.0 | 0.0
Settlements and reductions | 0.0 | 0.0 | 0.0 | 0.0
Balance, end of period | 14.2 | 0.0 | 14.2 | 0.0
Net change in unrealized gains relating to instruments still held at the reporting date | (17.2) | 0.0 | (26.1) | 0.0
Affiliate equity purchase obligations |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, beginning of period | 47.6 | 66.1 | 12.6 | 22.0
Net realized and unrealized losses (gains) | (3.6) | 1.3 | (3.9) | 2.2
Purchases and issuances | 7.9 | 12.3 | 48.5 | 83.0
Settlements and reductions | (26.9) | (31.8) | (32.2) | (59.3)
Balance, end of period | 25.0 | 47.9 | 25.0 | 47.9
Net change in unrealized gains relating to instruments still held at the reporting date | $ (3.5) | $ 0.0 | $ (3.8) | $ 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 https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + 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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