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Postretirement benefits Schedule of assumptions used to determine benefit obligation (Details) | Dec. 31, 2020 | Dec. 31, 2019
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Other Postretirement Benefits Plan [Member] |  |
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] |  |
Benefit Obligation, Discount Rate | 1.36% | 2.70%
Non - U.S. | Pension Plan [Member] |  |
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] |  |
Benefit Obligation, Discount Rate | 1.80% | 2.39%
Benefit Obligation, Rate of Compensation Increase | 3.24% | 3.26%
UNITED STATES | Pension Plan [Member] |  |
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] |  |
Benefit Obligation, Discount Rate | 2.32% | 3.20%
Interest crediting rate | 4.10% | 4.10%

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- Definition Interest crediting rate used to determine benefit obligation of defined benefit plan. + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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