Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Actual Return on Plan Assets

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- Definition

Defined Benefit Plan, Pension Plan Benefit Obligation, Plan Assets, Outstanding

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Non-cash, Non-operating Pension Settlement Charge

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Non-cash, Non-operating Pension Settlement Charge, After Tax

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Non-cash, Non-operating Pension Settlement Charge, Per Share, After Tax

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Number of Retirees and Beneficiaries

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Notice period the entity is required to deliver before it can redeem an investment calculated using net asset value per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investments calculated by per unit, per membership interest, other equity or ownership interest and alternative investments.

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Amount of cost (reversal of cost) for pension and other postretirement benefits.

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Postretirement Benefit Plans - Additional Information (Detail) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Jun. 26, 2022 USD ($) retiree $ / shares	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($)	Sep. 26, 2021 USD ($) retiree
Defined Benefit Plan Disclosure [Line Items]
Outstanding pension benefit obligations and related plan assets	$ 4,300				$ 4,900
Non-cash, non-operating pension settlement charge	1,500	$ 1,500	$ 1,700
Non-cash, non-operating pension settlement charge, after tax	$ 1,200	$ 1,200	$ 1,300
Non-cash, non-operating pension settlement charge, per share, after tax (in dollars per share) \| $ / shares	$ 4.33	$ 4.33	$ 4.72
Assets set aside expected to be used to pay obligations of defined benefit pension plans and retiree medical and life insurance plans		$ 24,884	$ 37,361
Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Assets set aside expected to be used to pay obligations of defined benefit pension plans and retiree medical and life insurance plans		$ 689	556
Hedge funds \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Fair value, investments, entities that calculate net asset value per share, investment redemption, notice period		1 month
Commingled equity funds
Defined Benefit Plan Disclosure [Line Items]
Fair value, investments, entities that calculate net asset value per share, investment redemption, notice period		90 days
Private equity funds \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Fair value, investments, entities that calculate net asset value per share, investment redemption, notice period		8 years
Private equity funds \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Fair value, investments, entities that calculate net asset value per share, investment redemption, notice period		12 years
Real estate funds \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Fair value, investments, entities that calculate net asset value per share, investment redemption, notice period		8 years
Real estate funds \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Fair value, investments, entities that calculate net asset value per share, investment redemption, notice period		10 years
Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Gross benefit obligation		$ 1,000	1,300
Assets set aside expected to be used to pay obligations of defined benefit pension plans and retiree medical and life insurance plans		595	872
Net actuarial (losses)		331	625
Benefit plan expense		81	56	$ 59
Qualified Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for defined benefit pension plans		28,600	43,400
Actual return on plan assets		$ (5,923)	3,899
Actual return on plan assets (percent)		(18.00%)
Expected return on plan assets		$ 1,854	2,146	2,264
Gross benefit obligation		28,698	43,447	51,352
Assets set aside expected to be used to pay obligations of defined benefit pension plans and retiree medical and life insurance plans		23,228	35,192	$ 38,481
Net actuarial (losses)		$ (10,287)	$ (14,675)
Qualified Defined Benefit Pension Plans \| Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Outstanding pension benefit obligations and related plan assets					$ 4,900
Number of retirees and beneficiaries \| retiree	13,600				18,000