Investment in Joint Venture - Summarized Balance Sheet Information of Unconsolidated Joint Venture (Detail) - Joint Venture - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Current assets	$ 43,351	$ 47,600
Non-current assets	32,352	24,763
Total assets	75,703	72,363
Current liabilities	27,982	26,165
Non-current liabilities	5	22
Total liabilities	$ 27,987	$ 26,187

The amount of assets reported by an equity method investment of the entity.

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