Amount of commitments for future investments in private markets to be made over a number of years.

No definition available.

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- Definition

The percentage of board members, elected by employees and retirees for managing investments.

+ References

No definition available.

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- References

No definition available.

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- Definition

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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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Retirement-Related Benefits - Investment Strategy (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
U.S. \| Personal Pension Plan (PPP) \| Qualified Plans \| Equity securities
Investment Policies And Strategies
Target allocation (as a percent)	12.00%
U.S. \| Personal Pension Plan (PPP) \| Qualified Plans \| Fixed-income securities
Investment Policies And Strategies
Target allocation (as a percent)	80.00%
U.S. \| Personal Pension Plan (PPP) \| Qualified Plans \| Real estate
Investment Policies And Strategies
Target allocation (as a percent)	3.00%
U.S. \| Personal Pension Plan (PPP) \| Qualified Plans \| Other investments
Investment Policies And Strategies
Target allocation (as a percent)	5.00%
U.S. \| Personal Pension Plan (PPP) \| Qualified Plans \| Private equities and private real estate investments
Investment Policies And Strategies
Fair Value of plan assets	$ 3,870
Commitments for future investments in private markets	$ 1,203
Non-U.S. \| Maximum
Investment Policies And Strategies
Percentage of board members, elected by employees and retirees for managing investments (as a percent)	50.00%
Non-U.S. \| Equity securities
Investment Policies And Strategies
Target allocation (as a percent)	16.00%
Non-U.S. \| Fixed-income securities
Investment Policies And Strategies
Target allocation (as a percent)	70.00%
Non-U.S. \| Real estate
Investment Policies And Strategies
Target allocation (as a percent)	3.00%
Non-U.S. \| Other investments
Investment Policies And Strategies
Target allocation (as a percent)	11.00%
Pension Plans \| U.S.
Investment Policies And Strategies
Fair Value of plan assets	$ 54,386	$ 51,784	$ 48,213
Pension Plans \| Non-U.S.
Investment Policies And Strategies
Fair Value of plan assets	$ 43,832	$ 40,319	$ 36,758