Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Interest and other income (expense), net	$ 3,750			$ 1,463	$ 8,607	$ 1,161
Accrued liabilities	173,851				173,851		$ 134,332
Accounting Standards Update 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Tax benefit	$ 1,700				$ 24,100
Retained Earnings | Accounting Standards Update 2016-16
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Decrease to retained earnings			$ 1,300
Out of period adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Interest and other income (expense), net		$ (1,900)
Accrued liabilities		$ 1,900