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Restructuring - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Restructuring Cost and Reserve [Line Items] |  |  |
Total pretax restructuring costs | $ 933 |  |
2024 Restructuring Program |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected restructuring and related cost | $ 4,000 |  |
Estimate of cumulative pre tax costs that will be noncash | 60.00% |  |
Total pretax restructuring costs | $ 190 |  |
2019 Restructuring Program |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Estimate of cumulative pre tax costs that will be noncash | 30.00% |  |
Total pretax restructuring costs | $ 743 | $ 666 | $ 868
Estimate of cumulative pre tax costs that will result in cash outlays | 70.00% |  |
Cumulative costs since inception | $ 4,100 |  |

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- Definition Amount of costs incurred to date for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 + Details
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- Definition Amount expected to be recognized in earnings for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 420 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482017/420-10-50-1 + Details
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