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Fair Value Measurements - Quantitative Information About Level 3 (Details) - Discounted cash flow $ in Millions | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
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Contingent payment arrangements | Growth rates |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Contingent payment arrangement, measurement input | 0.07 |
Contingent payment arrangements | Growth rates | Minimum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Contingent payment arrangement, measurement input |  | 0.07
Contingent payment arrangements | Growth rates | Maximum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Contingent payment arrangement, measurement input |  | 0.08
Contingent payment arrangements | Growth rates | Weighted Average |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Contingent payment arrangement, measurement input | 0.07 | 0.07
Contingent payment arrangements | Discount rates |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Contingent payment arrangement, measurement input | 0.15 |
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 | Maximum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Contingent payment arrangement, measurement input |  | 0.16
Contingent payment arrangements | Discount rates | Weighted Average |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Contingent payment arrangement, measurement input |  | 0.15
Affiliate equity repurchase obligations | Growth rates | Minimum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | (0.04) | 0.00
Affiliate equity repurchase obligations | Growth rates | Maximum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.09 | 0.11
Affiliate equity repurchase obligations | Growth rates | Weighted Average |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.03 | 0.06
Affiliate equity repurchase obligations | Discount rates | Minimum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.14 | 0.12
Affiliate equity repurchase obligations | Discount rates | Maximum |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Obligations to related parties, measurement input | 0.16 | 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 | 0.15 | 0.14
Level 3 | Contingent payment arrangements |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Fair value liabilities | $ 1.9 | $ 9.4
Level 3 | Affiliate equity repurchase obligations |  |
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |
Fair value liabilities | $ 36.2 | $ 49.2

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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=99377789&loc=d3e19207-110258 + Details
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