Condensed Consolidated Statements of Cash Flows Condensed Consolidated Statement of Cash Flows (Supplemental Disclosure) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Cash and cash equivalents	$ 370	$ 217	$ 139
Restricted cash and restricted cash equivalents included in Other current assets	288	346	2,724
Restricted cash equivalents included in Other long-term assets	42	43	33
Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period	$ 700	$ 607	$ 2,896	$ 829