Balance Sheet Components - Balance Sheet Details (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Inventories:
Raw materials	$ 20,736	$ 14,322
Work in process	10,769	7,800
Finished goods	60,734	47,175
Total inventories	92,239	69,297
Prepaid expense
Prepaid commissions	11,622	13,176
Other prepaid expenses	16,422	15,470
Total prepaid expense	28,044	28,646
Property and equipment:
Equipment	70,343	64,384
Furniture and fixtures	6,881	6,517
Leasehold improvements	10,143	9,778
Software	37,574	35,607
Construction in progress	8,083	7,211
Property and equipment, gross	133,024	123,497
Accumulated depreciation and amortization	(92,805)	(81,486)
Total property and equipment, net	40,219	42,011
Other long term assets:
Capitalized software, net	36,713	33,233
Other assets	883	1,818
Total other long term assets, net	37,596	35,051
Accrued liabilities:
Advance payments from customers	7,780	7,030
Rebates and lease buyouts	5,943	4,025
Group purchasing organization fees	3,380	3,737
Taxes payable	5,575	4,003
Other accrued liabilities	10,383	12,400
Total accrued liabilities	$ 33,061	$ 31,195