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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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

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

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Retirement-Related Benefits - Investment Strategy (Details) - U.S. - Pension Plans	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Expected
Retirement-Related Benefits
Expected long-term returns on plan assets	5.25%	5.75%
Equity securities
Retirement-Related Benefits
Target allocation (as a percent)			12.00%	20.00%
Debt securities
Retirement-Related Benefits
Target allocation (as a percent)			79.00%	70.00%
Other investments
Retirement-Related Benefits
Target allocation (as a percent)			10.00%	10.00%