XML 92 R79.htm IDEA: XBRL DOCUMENT v3.8.0.1
Change in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]    
Balance $ 168,764 $ 122,748
Balance 591,548 168,764
Accumulated Other Comprehensive Income (Loss)    
Accumulated Other Comprehensive Income (Loss) [Line Items]    
Balance (13,749) (8,566)
Other comprehensive income (loss) 7,386 (5,183)
Balance (6,363) (13,749)
Unrealized gain (loss) on investments    
Accumulated Other Comprehensive Income (Loss) [Line Items]    
Balance (5) (11)
Other comprehensive income (loss) 5 6
Balance   (5)
Foreign currency translation adjustment    
Accumulated Other Comprehensive Income (Loss) [Line Items]    
Balance (13,744) (8,555)
Other comprehensive income (loss) 7,381 (5,189)
Balance $ (6,363) $ (13,744)