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Contingencies - Narratives (Details)		12 Months Ended
	Apr. 23, 2018 USD ($)	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Related Party Tax Agreement Percent Of Savings	85.00%
Due to Related Parties	$ 0	$ 40,900,000	$ 89,900,000	$ 86,500,000
Related party payable - tax receivable agreement		21,752,000	27,857,000
Increase (Decrease) in Due to Related Parties		21,100,000
Long-term debt - affiliate		$ 19,098,000	$ 62,014,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		100.00%
London Interbank Offered Rate (LIBOR) [Member]
Loss Contingencies [Line Items]
Due to Related Party, Basis Spread on Variable Rate	0.0100
Minimum
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		$ 55,000,000
Maximum
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss		$ 70,000,000
Profit Units | LTIP
Loss Contingencies [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | shares		30,000
Outstanding Voting Power percentage		0.70
Outstanding Voting Power Percentage Minimum		0.30
Threshold Value		$ 855,000,000

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