Accounts Payable, Accrued Expenses and Other Liabilities - Components of Current Portion of Accounts Payable, Accrued Expenses and Other Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Accounts payable and accrued expenses	$ 110,271	$ 161,988
Redeemable preferred partnership units	93,480	0
Outside broker payable	54,873	74,280
Payroll taxes payable	53,027	45,612
Corporate taxes payable	38,964	69,237
Derivative liability	42,863	25,661
Right-of-use liabilities	28,645	27,184
Credit enhancement deposit	25,000	0
Contingent consideration	18,210	13,107
Total	$ 465,333	$ 417,069