Balance Sheet Details - Schedule of Other Non-Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Other Liabilities Noncurrent [Abstract]
Unrecognized tax benefits (including interest)	$ 4,698	$ 4,660
Contingent consideration - acquisitions	1,358	1,959
Deferred revenue	1,140	983
Other	2,977	2,859
Total other non-current liabilities	$ 10,173	$ 10,461

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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