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Employee benefit plans - Health Care Cost Trend Rates Related to U.S. Plan (Details) - United States | Dec. 31, 2022 | Dec. 31, 2021
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Pre-age 65 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Healthcare Cost Trend Rate | 5.80% | 6.91%
Ultimate Trend Rate | 4.50% | 4.45%
Post-age 65 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Healthcare Cost Trend Rate | 6.50% | 8.27%
Ultimate Trend Rate | 4.50% | 4.40%

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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. + References No definition available. + Details
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + 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 (l) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Ultimate trend rate for health care cost for defined benefit postretirement 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 (l) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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