Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Changes in Accumulated Other Comprehensive Income, Net of Income Taxes (Detail)

v3.8.0.1
Stockholders' Equity - Changes in Accumulated Other Comprehensive Income, Net of Income Taxes (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance, December 31, 2016     $ 810  
Other comprehensive income (loss) before reclassifications     260  
Amounts reclassified from accumulated other comprehensive income (loss)     0  
Net current-period other comprehensive income (loss) $ 64 $ (59) 260 $ 1,082
Ending balance, September 30, 2017 1,070   1,070  
Unrealized gains and (losses) of available-for-sale securities [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance, December 31, 2016     (255)  
Other comprehensive income (loss) before reclassifications     325  
Amounts reclassified from accumulated other comprehensive income (loss)     0  
Net current-period other comprehensive income (loss)     325  
Ending balance, September 30, 2017 70   70  
Foreign currency translation [Member]        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Beginning balance, December 31, 2016     1,065  
Other comprehensive income (loss) before reclassifications     (65)  
Amounts reclassified from accumulated other comprehensive income (loss)     0  
Net current-period other comprehensive income (loss)     (65)  
Ending balance, September 30, 2017 $ 1,000   $ 1,000