XML 50 R39.htm IDEA: XBRL DOCUMENT v3.8.0.1
Depreciation Expense Related to Property and Equipment (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Property Plant And Equipment [Abstract]        
Depreciation expense $ 454 $ 597 $ 1,350 $ 1,775