v2.4.1.9
Segment Information - Additional Information (Detail)
3 Months Ended
Mar. 31, 2015
Segment
Mar. 31, 2014
Segment Reporting Information [Line Items]    
Number of reportable segments 2us-gaap_NumberOfReportableSegments  
Number of customers individually accounting for more than ten percent of total operating revenues No single customer accounted for more than 10% of our total operating revenues No single customer accounted for more than 10% of our total operating revenues