Balance Sheet Components - Balance Sheet Components (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Inventories:
Raw materials	$ 31,331		$ 32,511
Work in process	7,620		8,726
Finished goods	69,060		59,631
Total inventories	108,011		100,868
Other long-term assets:
Capitalized software, net	85,070		56,819
Unbilled receivables	12,260		16,481
Debt Issuance Costs	4,700		4,583
Other assets	1,006		1,313
Total other long-term assets	103,036		74,613
Accrued liabilities:
Operating lease liabilities, current portion	10,058	$ 10,300
Advance payments from customers	4,006		8,993
Rebates and lease buyouts	14,911		11,076
Group purchasing organization fees	5,934		4,455
Taxes payable	3,744		5,885
Other accrued liabilities	16,914		12,638
Total accrued liabilities	$ 55,567		$ 43,047