CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Statement of Cash Flows [Abstract]
Cash and cash equivalents	$ 1,509	$ 221	$ 244
Restricted cash included in Prepaid expenses and other current assets	11		10
Total cash, cash equivalents, and restricted cash at end of the period	$ 1,520	$ 232	$ 254	$ 114