Revenue from Contracts with Customers - Schedule of Information About Balances Associated with Contracts with Customers (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Disaggregation Of Revenue [Line Items]
Receivables - Included in 'Accounts receivable'	$ 27,274	$ 32,248
Receivables - Included in 'Due from affiliates'	38,658	49,613
Revenue from Contracts with Customers
Disaggregation Of Revenue [Line Items]
Receivables - Included in 'Accounts receivable'	23,546	27,521
Receivables - Included in 'Due from affiliates'	34,725	42,234
Total contract balances	$ 58,271	$ 69,755

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, classified as current.

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Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due within 1 year (or 1 business cycle).

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