Balance Sheet Components (Schedule Of Accounts Receivable And Related Allowances) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross accounts receivable	$ 437,891	$ 333,080
Allowance for Doubtful Accounts Receivable, Current	(25,093)	(19,241)
Total accounts receivable, net	412,798	313,839
Allowance for Doubtful Accounts, Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Doubtful Accounts Receivable, Current	(1,257)	(1,255)
Allowance for Sales Returns [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Doubtful Accounts Receivable, Current	(20,189)	(13,506)
Allowance For Price Protection [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for Doubtful Accounts Receivable, Current	$ (3,647)	$ (4,480)