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Employee Benefit Plans (Obligations and Funded Status) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Pension Benefits |  |  |
Change in benefit obligations: |  |  |
Benefit obligations at January 1, | $ 12,182 | $ 12,873 |
Service costs | 187 | 215 | $ 226
Interest costs | 328 | 342 | 363
Plan participants’ contributions | 0 | 0 |
Plan amendments | 8 | 1 |
Net actuarial (gains) losses | (2,609) | (363) |
Acquisition, divestitures, settlements and curtailments | (45) | (111) |
Benefits paid | (630) | (665) |
Effect of foreign currency translation | (123) | (110) |
Benefit obligations at December 31, | 9,298 | 12,182 | 12,873
Change in plan assets |  |  |
Estimated fair value of plan assets at January 1, | 10,971 | 11,256 |
Actual return on plan assets | (2,095) | 310 |
Acquisition, divestitures and settlements | (38) | (35) |
Plan participants’ contributions | 0 | 0 |
Employer contributions | 152 | 163 |
Benefits paid | (630) | (665) |
Effect of foreign currency translation | (66) | (58) |
Estimated fair value of plan assets at December 31, | 8,294 | 10,971 | 11,256
Over (under) funded status at December 31, | (1,004) | (1,211) |
Amounts recognized in the consolidated balance sheets |  |  |
Other assets | 428 | 640 |
Other liabilities | (1,432) | (1,851) |
Net amount recognized | (1,004) | (1,211) |
Accumulated other comprehensive (income) loss: |  |  |
Net actuarial (gains) losses | 2,277 | 2,416 |
Prior service costs (credit) | (36) | (55) |
AOCI, before income tax | 2,241 | 2,361 |
Accumulated benefit obligation | 9,185 | 11,934 |
Other Postretirement Benefits |  |  |
Change in benefit obligations: |  |  |
Benefit obligations at January 1, | 1,138 | 1,252 |
Service costs | 4 | 4 | 5
Interest costs | 34 | 37 | 42
Plan participants’ contributions | 32 | 32 |
Plan amendments | 0 | 0 |
Net actuarial (gains) losses | (289) | (96) |
Acquisition, divestitures, settlements and curtailments | 0 | 8 |
Benefits paid | (125) | (99) |
Effect of foreign currency translation | 0 | 0 |
Benefit obligations at December 31, | 794 | 1,138 | 1,252
Change in plan assets |  |  |
Estimated fair value of plan assets at January 1, | 1,443 | 1,492 |
Actual return on plan assets | (43) | 14 |
Acquisition, divestitures and settlements | 0 | (1) |
Plan participants’ contributions | 32 | 32 |
Employer contributions | (3) | 5 |
Benefits paid | (125) | (99) |
Effect of foreign currency translation | (1) | 0 |
Estimated fair value of plan assets at December 31, | 1,303 | 1,443 | $ 1,492
Over (under) funded status at December 31, | 509 | 305 |
Amounts recognized in the consolidated balance sheets |  |  |
Other assets | 796 | 788 |
Other liabilities | (287) | (483) |
Net amount recognized | 509 | 305 |
Accumulated other comprehensive (income) loss: |  |  |
Net actuarial (gains) losses | (498) | (332) |
Prior service costs (credit) | 0 | 0 |
AOCI, before income tax | (498) | (332) |
Changes to financial assumptions [Member] | Pension Benefits |  |  |
Change in benefit obligations: |  |  |
Net actuarial (gains) losses | (2,600) | (389) |
Changes to financial assumptions [Member] | Other Postretirement Benefits |  |  |
Change in benefit obligations: |  |  |
Net actuarial (gains) losses | (276) | (34) |
Changes to demographic assumptions [Member] | Pension Benefits |  |  |
Change in benefit obligations: |  |  |
Net actuarial (gains) losses |  | 0 |
Changes to demographic assumptions [Member] | Other Postretirement Benefits |  |  |
Change in benefit obligations: |  |  |
Net actuarial (gains) losses |  | (4) |
Changes to Plan Experience [Member] | Pension Benefits |  |  |
Change in benefit obligations: |  |  |
Net actuarial (gains) losses | 14 | 26 |
Changes to Plan Experience [Member] | Other Postretirement Benefits |  |  |
Change in benefit obligations: |  |  |
Net actuarial (gains) losses | $ (13) | $ (58) |

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- Definition Amount of increase (decrease) in plan obligations from purchases, sales, curtailments and settlement of plan assets. + References No definition available. + Details
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + 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 (e) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Amount of foreign currency translation gain (loss) which increases (decreases) plan assets 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 (b)(2) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment. + 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 (d)(iv)(02)(B) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 + Details
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for 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 (h)(1) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 + Details
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