Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2017 Segment Customer
Summary Of Significant Accounting Policies [Line Items]
Number of reporting segments | Segment	1
Revenue | Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Number of customers | Customer	4
Revenue | Customer Concentration Risk | Customer One
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	15.00%
Revenue | Customer Concentration Risk | Customer Two
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	14.00%
Revenue | Customer Concentration Risk | Customer Three
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	11.00%
Revenue | Customer Concentration Risk | Customer Four
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	10.00%