Organization and Summary of Significant Accounting Policies - Impact of the Adoption of ASC 842 (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property and equipment, net	$ 41,023	$ 42,549	$ 75,355
Operating lease right-of-use assets	94,203	93,207	0
Deferred tax assets	113,660	125,327	126,492
Other current liabilities	52,622	41,056	30,907
Operating lease liabilities, non-current	89,705	88,230	0
Finance lease liabilities, non-current	0	0	35,431
Other long-term liabilities	25,351	24,437	31,851
Retained earnings	$ 1,484,777	1,194,505	$ 1,190,803
Adjustments for the Adoption of ASC 842
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property and equipment, net		(32,806)
Operating lease right-of-use assets		93,207
Deferred tax assets		(1,165)
Operating lease liabilities, non-current		88,230
Finance lease liabilities, non-current		(35,431)
Other long-term liabilities		(7,414)
Retained earnings		3,702
Build-To-Suit Lease | Adjustments for the Adoption of ASC 842
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other current liabilities		(2,242)
Operating Lease | Adjustments for the Adoption of ASC 842
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other current liabilities		$ 12,391