Supplemental cash flow information (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for income taxes	$ 2,715	$ 4,395
Non-cash investing and financing activities:
Non-cash acquisition of equity securities	430
Insurance and Other [Member]
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for interest	892	879
Railroad, Utilities and Energy [Member]
Supplemental Cash Flow Information [Line Items]
Cash paid during the period for interest	$ 2,174	$ 2,149

Supplemental Cash Flow Information [Line Items]

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

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-Publisher FASB
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-Topic 230
-SubTopic 10
-Section 50
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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

+ References

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-Topic 230
-SubTopic 10
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- References

No definition available.

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- Definition

The amount of investments that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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