CONSOLIDATED FINANCIAL STATEMENT DETAILS - Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018
Other current assets:
Prepaid expenses	$ 97,609	$ 55,586
Capitalized costs to obtain a contract with a customer	71,548	69,817	$ 53,400
Capitalized downloadable search toolbar costs, net	21,985	33,365
Income taxes receivable	9,308	10,132
Other	48,917	59,353
Other current assets	$ 249,367	$ 228,253