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Fair Value Measurements - Quantitative Information About Level 3 (Details) - Level 3 - Affiliate equity repurchase obligations - Discounted cash flow $ in Millions | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
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Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Fair Value | $ 22.0 | $ 19.8
Growth rates | Minimum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | (0.05) | (0.09)
Growth rates | Maximum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.08 | 0.07
Growth rates | Weighted Average |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.03 | 0.05
Discount rates | Minimum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.14 | 0.14
Discount rates | Maximum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.16 | 0.17
Discount rates | Weighted Average |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.15 | 15

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- Definition Fair value of financial and nonfinancial obligations. + 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 (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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