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Fair Value Measurements - Quantitative Information About Level 3 (Details) - Discounted cash flow $ in Millions | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
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Contingent payment arrangements | Growth rates | Minimum |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Contingent payment arrangement, measurement input | [1] |  | 0.07
Contingent payment arrangements | Growth rates | Weighted Average |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Contingent payment arrangement, measurement input | [2] |  | 0.07
Contingent payment arrangements | Discount rates | Minimum |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Contingent payment arrangement, measurement input |  |  | 0.15
Contingent payment arrangements | Discount rates | Weighted Average |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Contingent payment arrangement, measurement input | [2] |  | 0.15
Affiliate equity repurchase obligations | Growth rates | Minimum |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Obligations to related parties, measurement input | [1] | (0.09) | (0.04)
Affiliate equity repurchase obligations | Growth rates | Maximum |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Obligations to related parties, measurement input | [1] | 0.07 | 0.09
Affiliate equity repurchase obligations | Growth rates | Weighted Average |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Obligations to related parties, measurement input | [1],[2] | 0.05 | 0.03
Affiliate equity repurchase obligations | Discount rates | Minimum |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Obligations to related parties, measurement input |  | 0.14 | 0.14
Affiliate equity repurchase obligations | Discount rates | Maximum |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Obligations to related parties, measurement input |  | 0.17 | 0.16
Affiliate equity repurchase obligations | Discount rates | Weighted Average |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Obligations to related parties, measurement input | [2] | 0.15 | 0.15
Level 3 | Contingent payment arrangements |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Fair value liabilities |  | $ 0.0 | $ 1.9
Level 3 | Affiliate equity repurchase obligations |  |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |
Fair value liabilities |  | $ 19.8 | $ 36.2
[1] | Includes transfers from Redeemable non-controlling interests.
[2] | Calculated by comparing the relative fair value of an arrangement or obligation to its respective total.

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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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