CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Reconciliation of cash, cash equivalents and restricted cash and cash equivalents at end of period:
Cash and cash equivalents	$ 351	$ 118	$ 553
Restricted cash and cash equivalents included in other current assets	$ 25	$ 7	$ 28
Restricted Cash and Cash Equivalents, Current, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current	Other Assets, Current
Restricted cash and cash equivalents included in restricted funds	$ 69	$ 69	$ 67
Restricted Cash and Cash Equivalents, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Restricted Cash and Investments, Noncurrent	Restricted Cash and Investments, Noncurrent	Restricted Cash and Investments, Noncurrent
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$ 445	$ 194	$ 648

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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