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Employee Benefit Plans - Schedule of Allocation of Plan Assets (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Defined Benefit Plan Disclosure [Line Items] |  |
Amount | $ 2,422 | $ 2,327
Percent of total assets | 100.00% | 100.00%
Growth-Oriented |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Amount | $ 1,271 | $ 1,434
Percent of total assets | 52.00% | 62.00%
Equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Amount | $ 1,142 | $ 1,249
Percent of total assets | 47.00% | 54.00%
Fixed Income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Amount | $ 114 | $ 144
Percent of total assets | 4.00% | 6.00%
Cash and Cash Equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Amount | $ 15 | $ 41
Percent of total assets | 1.00% | 2.00%
Immunizing |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Amount | $ 1,151 | $ 893
Percent of total assets | 48.00% | 38.00%
Fixed Income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Amount | $ 911 | $ 777
Percent of total assets | 38.00% | 33.00%
Cash and Cash Equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Amount | $ 240 | $ 116
Percent of total assets | 10.00% | 5.00%

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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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