Balance Sheet Components - Schedule of Gross Accounts Receivable Balance Concentrations by Major Category (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Accounts Notes And Loans Receivable [Line Items]
Gross accounts receivable	$ 38,493	$ 39,360
Medicare
Accounts Notes And Loans Receivable [Line Items]
Gross accounts receivable	10,583	12,500
Medicaid Or Other Government
Accounts Notes And Loans Receivable [Line Items]
Gross accounts receivable	564	617
Private Insurance
Accounts Notes And Loans Receivable [Line Items]
Gross accounts receivable	2,740	3,475
Patient Responsibility
Accounts Notes And Loans Receivable [Line Items]
Gross accounts receivable	3,898	3,227
Business To Business And Other Receivables
Accounts Notes And Loans Receivable [Line Items]
Gross accounts receivable	$ 20,708	$ 19,541