Balance Sheet Details (Schedule of Accumulated Other Comprehensive Income) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018 USD ($)
Accumulated Other Comprehensive Income [Roll Forward]
Balance as of December 31, 2017	$ 106,101
Balance as of September 30, 2018	106,119
Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income [Roll Forward]
Balance as of December 31, 2017	12,076
Other comprehensive income before reclassification	(1,457)
Amounts reclassified from accumulated other comprehensive income	57
Net other comprehensive income for the nine months ended September 30, 2018	(1,400)
Balance as of September 30, 2018	10,676
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income [Roll Forward]
Balance as of December 31, 2017	12,957
Other comprehensive income before reclassification	(1,457)
Amounts reclassified from accumulated other comprehensive income	0
Net other comprehensive income for the nine months ended September 30, 2018	(1,457)
Balance as of September 30, 2018	11,500
Defined Benefit Pension Plan
Accumulated Other Comprehensive Income [Roll Forward]
Balance as of December 31, 2017	(881)
Other comprehensive income before reclassification	0
Amounts reclassified from accumulated other comprehensive income	57
Net other comprehensive income for the nine months ended September 30, 2018	57
Balance as of September 30, 2018	$ (824)