CONSOLIDATED FINANCIAL STATEMENT DETAILS - Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Other current assets:
Capitalized costs to obtain a contract with a customer	$ 69,817	$ 0
Prepaid expenses	55,586	49,350
Capitalized downloadable search toolbar costs, net	33,365	31,588
Income taxes receivable	10,132	33,239
Production costs	2,260	18,570
Other	57,093	52,627
Other current assets	$ 228,253	$ 185,374