CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Millions, $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Cash and cash equivalents	$ 1,755	$ 1,491
Prepayments and other current assets	174	155
Property and equipment, net ($212 and $137 attributable to our VIEs)	14,976	16,045
Accounts payable	444	399
Accrued expenses and other current liabilities	$ 1,323	$ 1,217
Common stock outstanding (in shares)	682	670
Treasury stock (in shares)	48	46
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Variable Interest Entity, Primary Beneficiary
Cash and cash equivalents	$ 8	$ 14
Prepayments and other current assets	4	6
Property and equipment, net ($212 and $137 attributable to our VIEs)	212	137
Deferred charges and other	26	35
Accounts payable	97	41
Accrued expenses and other current liabilities	2	1
Deferred credits and other liabilities	$ 18	$ 5

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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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Face amount or stated value per share of common stock.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Aggregated carrying amounts of obligations as of the balance sheet date, excluding long-term debt, incurred as part of the normal operations that are expected to be paid after one year or beyond the normal operating cycle, if longer. Alternate captions include Total Deferred Credits and Other Liabilities.

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Amount of current assets classified as other.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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