Defined Benefit Plan, Actual Percent Return On Plan Assets

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Average Investment Term, Alternative Investments

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Change in basis points

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- Definition

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

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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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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No definition available.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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No definition available.

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- Definition

States the frequency (for example, annually, semi-annually, quarterly) with which the entity can redeem its investment, or portion thereof, for each of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments), by major category.

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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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The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

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Retirement Benefits Amounts in Paragraphs - Retirement Benefits (Details 9) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Contribution Plans Disclosure (Amounts in paragraphs)
Defined Contribution Plan, Employer Discretionary Contribution Amount		$ 590	$ 481	$ 403
Pension and post-retirement benefits disclosures (Amounts in paragraphs)
Accumulated benefit obligation for all defined benefit pension plans		$ 39,600	$ 36,500
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Actual Percent Return On Plan Assets		16.20%	19.10%
Yearly Discount Rate change in basis points		(71)	(92)
Pension Benefits
Defined Contribution Plans Disclosure (Amounts in paragraphs)
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		$ 98
Defined Benefit Plan, Plan Assets, Contributions by Employer		$ 851	$ 221
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets		8.00%	8.00%
Pension Benefits \| Subsequent Event [Member]
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	7.50%
Pension Benefits \| Voluntary Contributions [Member]
Defined Contribution Plans Disclosure (Amounts in paragraphs)
Defined Benefit Plan, Plan Assets, Contributions by Employer		$ 750
OPB contributions
Defined Contribution Plans Disclosure (Amounts in paragraphs)
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		43
Defined Benefit Plan, Plan Assets, Contributions by Employer		$ 36	$ 42
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets		7.66%	7.67%
OPB contributions \| Subsequent Event [Member]
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	7.22%
U.S. Equity Securities [Member]
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 0	$ 0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency		daily, monthly or quarterly
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period		90 days
International Equity Securities [Member]
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 0	0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency		daily, monthly or quarterly
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period		90 days
Fixed Income Funds
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 2	0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency		daily, monthly or quarterly
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period		30 days
Hedge Funds [Member]
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 9	8
OpportunisticFunds
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		1,900	1,300
Private Equity Funds [Member]
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 2,300	1,900
Average investment term, alternative investments		10 years
Real Estate Funds
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 60	$ 60
Average investment term, alternative investments		10 years
Minimum \| Hedge Funds [Member]
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period		5 years
Minimum \| OpportunisticFunds
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Average investment term, alternative investments		5 years
Maximum \| Hedge Funds [Member]
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period		10 years
Maximum \| OpportunisticFunds
Information About Plan Assets (Amounts in paragraphs) [Abstract]
Average investment term, alternative investments		10 years