Liabilities - Components of Accounts Payable, Accrued Expenses, and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Accounts payable	$ 23,643	$ 18,289
Accrued expenses	5,498	5,298
Subsidiary unit awards	2,596	2,506
Other current liabilities	4,728	2,207
Accounts payable, accrued expenses and other current liabilities	$ 36,465	$ 28,300