Revenue Recognition - Schedule of Significant Changes in Contract Assets and Contract Liabilities (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($)
Changes in the Contract Assets
Transferred to receivables from contract assets recognized at January 1, 2017	$ 752
Changes in the Contract Liabilities
Revenue recognized that was included in the contract liability (def. revenue) balance at Jan. 1, 2017	2,627
Increases due to cash received, excluding amounts recognized as revenue during the period	$ 929