Related Party Transactions - Related Party Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Contract assets	$ 78,900	$ 73,000	$ 63,400	$ 50,600
Operating lease right-of-use assets	30,449	32,579
Other	36,757	22,903
Due to related parties	119,759	127,882
Operating lease liabilities	25,640	27,206
Affiliated Entity
Related Party Transaction [Line Items]
Contract assets	72,839	68,133	$ 61,500	$ 49,800
Operating lease right-of-use assets	21,992	23,047
Other	2,542	6,381
Total Related Party Assets	97,373	97,561
Operating lease liabilities	15,746	16,282
Other	21	197
Total Related Party Liabilities	119,759	127,882
Loan Reimbursement Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Due to related parties	94,992	102,403
Payable To Holders Of Management Company's Class B Interests \| Affiliated Entity
Related Party Transaction [Line Items]
Due to related parties	$ 9,000	$ 9,000

Related Party Assets

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Total Related Party Liabilities

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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