Cash, Cash Equivalents and Restricted Cash - (Tables)

6 Months Ended

Jun. 30, 2018

Short-Term Investments And Fair Value Measurement [Abstract]

Schedule of Cash and Cash Equivalents

	As of June 30, 2018
	Cash and cash equivalents		Non-current Assets (1)
	(in thousands)
Cash	$	2,232,132	$	6,351
Level 1 securities:
Money market funds	1,524,225		1,286
Level 2 securities:
Time Deposits	150,000		—

	As of December 31, 2017
	Cash and cash equivalents		Non-current Assets (1)
	(in thousands)
Cash	$	2,072,296	$	4,367
Level 1 securities:
Money market funds	449,734		1,276
Level 2 securities:
Time Deposits	300,765		—

(1) Restricted cash related to workers compensation deposits and letter of credit agreements. Balance as of June 30, 2018 is included in cash, cash equivalents, and restricted cash on the Consolidated Statements of Cash Flows.