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Related Party Transactions (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Prior Owner | Other Liabilities |  |
Related Party Transactions |  |
Investment partnerships with prior owners | $ 49,700,000 | $ 61,200,000
Affiliated Entity |  |
Related Party Transactions |  |
Imputed interest expenses of contingent payment arrangements | 600,000 | 6,600,000
Affiliated Entity | Other Liabilities |  |
Related Party Transactions |  |
Contingent liabilities arrangements to related parties | 1,900,000 | 9,400,000
Payments associated with contingent liabilities arrangements to related parties | $ 8,800,000 | $ 6,800,000.0

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