CONSOLIDATED FINANCIAL STATEMENT DETAILS - Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents	$ 420,985	$ 390,565	$ 380,563	$ 336,984
Restricted cash included in other current assets	379	504	1,419	1,417
Restricted cash included in other non-current assets	412	409	420	420
Total cash and cash equivalents, and restricted cash as shown on the consolidated statement of cash flows	$ 421,776	$ 391,478	$ 382,402	$ 338,821