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

No definition available.

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- References

No definition available.

+ Details

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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RETIREMENT-RELATED BENEFITS - Investment Strategy (Details) - Pension Plans - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
U.S.
Investment Policies And Strategies
Fair Value of plan assets	$ 52,694	$ 51,405	$ 51,716
U.S. \| Personal Pension Plan (PPP) \| Qualified Plans
Investment Policies And Strategies
Fair Value of plan assets	$ 52,694	51,405
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)	79.00%
U.S. \| Personal Pension Plan (PPP) \| Qualified Plans \| Real estate
Investment Policies And Strategies
Target allocation (as a percent)	4.00%
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	$ 4,683
Commitments for future investments in private markets	1,845
Non-U.S.
Investment Policies And Strategies
Fair Value of plan assets	$ 40,798	$ 36,020	$ 35,748
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)	23.00%
Non-U.S. \| Fixed-income securities
Investment Policies And Strategies
Target allocation (as a percent)	62.00%
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)	12.00%