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Related Party Transactions (Details) - USD ($) $ in Millions | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Related Party Transactions |  |
Other liabilities | $ 216.3 | $ 182.4
Prior Owner | Private Equity Investment Partnerships of Affiliate |  |
Related Party Transactions |  |
Other liabilities | 57.0 | 61.2
Affiliated Entity | Other Liabilities |  |
Related Party Transactions |  |
Contingent payment arrangements liability | $ 9.8 | $ 9.4

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