Condensed Consolidated Statements of Cash Flows $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Operating Activities
Net income	$ 1,673	$ 4,812	$ 3,969
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation	553	1,652	1,653
Deferred and other income taxes		189	327
Other operating activities, net		(67)	119
Changes in current assets and liabilities:
Accounts receivable, net		(174)	30
Materials and supplies		(26)	102
Other current assets		19	(7)
Accounts payable and other current liabilities		(4)	(215)
Income and other taxes		102	15
Cash provided by operating activities		6,503	5,993
Investing Activities
Capital investments		(1,945)	(2,294)
Proceeds from asset sales		120	119
Maturities of short-term investments (Note 13)		64	106
Purchases of short-term investments (Note 13)		(40)	(106)
Other investing activities, net		9	94
Cash used in investing activities		(1,792)	(2,081)
Financing Activities
Share repurchase programs (Note 16)		(5,846)	(2,956)
Debt issued (Note 14)		3,901	4,004
Dividends paid		(2,045)	(1,974)
Debt repaid		(1,120)	(832)
Debt exchange		(270)	(327)
Net issued/(repaid) commercial paper (Note 14)		125	(2)
Other financing activities, net		(36)	(63)
Cash used in financing activities		(5,291)	(2,150)
Net change in cash, cash equivalents, and restricted cash		(580)	1,762
Cash, cash equivalents, restricted cash, beginning balance		1,818	856
Cash, cash equivalents, restricted cash, ending balance	1,238	1,238	2,618
Non-cash investing and financing activities:
Capital investments accrued but not yet paid		151	152
Common shares repurchased but not yet paid	80	80
Cash (paid for)/received from:
Income taxes, net of refunds		(1,241)	(925)
Interest, net of amounts capitalized		(904)	(911)
Reconciliation of cash, cash equivalents, and restricted cash to the Condensed Consolidated Statement of Financial Position
Cash and cash equivalents, at carry value	1,194	1,194	2,601
Cash, cash equivalents, restricted cash, ending balance	1,238	1,238	2,618
Other Current Assets [Member]
Reconciliation of cash, cash equivalents, and restricted cash to the Condensed Consolidated Statement of Financial Position
Restricted Cash and Cash Equivalents	32	32	5
Other Noncurrent Assets [Member]
Reconciliation of cash, cash equivalents, and restricted cash to the Condensed Consolidated Statement of Financial Position
Restricted Cash and Cash Equivalents	$ 12	$ 12	$ 12