Organization and Summary of Significant Accounting Policies (Details)	3 Months Ended										12 Months Ended
	Dec. 31, 2018 USD ($) supplier		Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) supplier		Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) supplier segment		Dec. 31, 2017 USD ($) supplier		Dec. 31, 2016 USD ($)		Jan. 01, 2019 USD ($)	Jan. 01, 2018 USD ($)	Dec. 31, 2015 USD ($)
Restricted Cash and Cash Equivalents Items [Line Items]
Letter of credit outstanding, amount	$ 4,000,000										$ 4,000,000
Restricted cash pledged as collateral						$ 4,000,000							$ 4,000,000
Letter of credit						1,100,000							1,100,000
Foreign Currency
Foreign currency transaction gains (losses)											300,000		(500,000)		$ (700,000)
Inventory
Inventory write-down											20,800,000		28,100,000		12,100,000
Contract manufacturer and supplier liability											$ 0		21,200,000		6,200,000
Property, Plant and Equipment [Line Items]
Estimated useful life											3 years
Impairment of Long-Lived Assets and Investments
Impairment of long-lived assets and investments											$ 0		0		0
Deferred Revenue Arrangement [Line Items]
Revenue, description of timing											30 days with some large high volume customers having extended terms up to 60 days
Capitalized contract cost, amortization period	5 years										5 years
Capitalized contract cost	$ 6,400,000										$ 6,400,000
Warranty
Warranty term on hardware products											1 year
Warranty term on software embedded in products											90 days
Segment Reporting
Number of business activities | segment											1
Number of reportable segments | segment											1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefits included in income taxes	7,800,000		$ 22,300,000	$ 20,100,000	$ 25,300,000	38,300,000		$ 23,800,000	$ 19,100,000	$ 28,800,000	$ 75,500,000		110,000,000
Excess tax benefits included in APIC															42,084,000
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings	1,190,803,000					859,114,000					1,190,803,000		859,114,000
Prepaid expenses and other current assets	162,321,000					177,330,000					162,321,000		177,330,000
Other assets	22,704,000					18,891,000					22,704,000		18,891,000
Deferred tax assets	126,492,000					65,125,000					126,492,000		65,125,000
Deferred revenue	587,227,000					498,740,000	[1]				587,227,000		498,740,000	[1]
Cash, cash equivalents, restricted cash	$ 654,164,000	[2]				$ 864,697,000	[2]				654,164,000	[2]	864,697,000	[2]	572,168,000	[2]			$ 691,367,000
Net cash provided by (used in) investing activities											$ (755,113,000)		$ (391,320,000)	[3]	(325,775,000)	[3]
Supplier Concentration Risk
Product Information [Line Items]
Number of suppliers | supplier	3					3					3		3
Accounting Standards Update 2016-18
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash, cash equivalents, restricted cash						$ 5,500,000							$ 5,500,000		4,200,000				$ 4,000,000
Net cash provided by (used in) investing activities													$ (1,300,000)		$ (200,000)
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings																		$ 3,500,000
Prepaid expenses and other current assets																		2,000,000
Other assets																		2,200,000
Deferred tax assets																		(700,000)
Deferred revenue																		$ (16,500,000)
Scenario, Forecast | Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability, right of use asset																	$ 70,900,000
Operating lease liability																	$ 79,400,000
Maximum
Deferred Revenue Arrangement [Line Items]
PCS term of contract											3 years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of the awards											5 years
Finite-Lived Intangible Assets [Line Items]
Weighted average useful life (in years)											7 years
Minimum
Deferred Revenue Arrangement [Line Items]
PCS term of contract											1 year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of the awards											2 years
Finite-Lived Intangible Assets [Line Items]
Weighted average useful life (in years)											1 year
Building
Property, Plant and Equipment [Line Items]
Estimated useful life											30 years
Customer A | Accounts Receivable | Credit Concentration Risk
Product Information [Line Items]
Percentage of total per significant customer											35.00%		30.00%
Customer A | Revenue | Credit Concentration Risk
Product Information [Line Items]
Percentage of total per significant customer											27.00%		16.00%		16.00%
Customer B | Accounts Receivable | Credit Concentration Risk
Product Information [Line Items]
Percentage of total per significant customer											10.00%		18.00%
Other Assets
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 4,200,000					$ 5,500,000					$ 4,200,000		$ 5,500,000

[1] The beginning balance of the year ended December 31, 2018 excludes $16.5 million that was reclassified to other current liabilities and other long-term liabilities at January 1, 2018 as a result of our adoption of ASC 606. See Note 1 for details.

[2] See Note 4 of the accompanying notes for a reconciliation of the ending balance of cash, cash equivalents and restricted cash as shown in this consolidated statements of cash flows.

[3] Net cash used in investing activities for the years ended December 31 of 2017 and 2016, respectively, was adjusted as a result of our adoption of ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash, in the first quarter of 2018. See Note 1 of the accompanying notes for details of the adjustments.