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Employee Benefits - Schedule of Changes in Fair Value of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Plan Asset
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1,411	$ 1,392	$ 1,431
Percentage of Plan Assets	100.00%	100.00%
Pension Plan Asset | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 289	$ 272
Pension Plan Asset | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	495	516
Pension Plan Asset | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31	32
Pension Plan Asset | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	596	572
Pension Plan Asset | Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 23	$ 40
Percentage of Plan Assets	2.00%	3.00%
Pension Plan Asset | Cash | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 23	$ 40
Pension Plan Asset | Cash | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Cash | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Cash | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | U.S. large cap
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 158	$ 155
Percentage of Plan Assets	11.00%	11.00%
Pension Plan Asset | U.S. large cap | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 40	$ 29
Pension Plan Asset | U.S. large cap | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | U.S. large cap | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | U.S. large cap | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	118	126
Pension Plan Asset | U.S. small cap
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 32	$ 34
Percentage of Plan Assets	2.00%	2.00%
Pension Plan Asset | U.S. small cap | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 32	$ 34
Pension Plan Asset | U.S. small cap | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | U.S. small cap | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | U.S. small cap | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | International
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 299	$ 258
Percentage of Plan Assets	21.00%	19.00%
Pension Plan Asset | International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Pension Plan Asset | International | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | International | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | International | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	299	258
Pension Plan Asset | Real estate fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 122	$ 120
Percentage of Plan Assets	9.00%	9.00%
Pension Plan Asset | Real estate fund | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Pension Plan Asset | Real estate fund | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Real estate fund | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Real estate fund | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	122	120
Pension Plan Asset | REITs
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 7	$ 6
Percentage of Plan Assets	0.00%	0.00%
Pension Plan Asset | REITs | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Pension Plan Asset | REITs | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | REITs | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | REITs | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	6
Pension Plan Asset | U.S. Treasury securities and government bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 257	$ 232
Percentage of Plan Assets	19.00%	17.00%
Pension Plan Asset | U.S. Treasury securities and government bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 194	$ 169
Pension Plan Asset | U.S. Treasury securities and government bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13	1
Pension Plan Asset | U.S. Treasury securities and government bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | U.S. Treasury securities and government bonds | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50	62
Pension Plan Asset | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 459	$ 489
Percentage of Plan Assets	33.00%	35.00%
Pension Plan Asset | Corporate bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Pension Plan Asset | Corporate bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	459	489
Pension Plan Asset | Corporate bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Corporate bonds | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 5	$ 6
Percentage of Plan Assets	0.00%	0.00%
Pension Plan Asset | Mortgage-backed securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Pension Plan Asset | Mortgage-backed securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5	6
Pension Plan Asset | Mortgage-backed securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Mortgage-backed securities | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Municipal bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 18	$ 20
Percentage of Plan Assets	1.00%	2.00%
Pension Plan Asset | Municipal bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Pension Plan Asset | Municipal bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18	20
Pension Plan Asset | Municipal bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Municipal bonds | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Guarantee annuity contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 31	$ 32
Percentage of Plan Assets	2.00%	2.00%
Pension Plan Asset | Guarantee annuity contracts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Pension Plan Asset | Guarantee annuity contracts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Plan Asset | Guarantee annuity contracts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31	32
Pension Plan Asset | Guarantee annuity contracts | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 256	$ 253	$ 258
Percentage of Plan Assets	100.00%	100.00%
Postretirement Benefit Plan Assets | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 100	$ 97
Percentage of Plan Assets	100.00%	100.00%
Postretirement Benefit Plan Assets | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 25	$ 28
Percentage of Plan Assets	100.00%	100.00%
Postretirement Benefit Plan Assets | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 131	$ 128
Percentage of Plan Assets	100.00%	100.00%
Postretirement Benefit Plan Assets | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 98	$ 95
Postretirement Benefit Plan Assets | Level 1 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	11
Postretirement Benefit Plan Assets | Level 1 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5	4
Postretirement Benefit Plan Assets | Level 1 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	81	80
Postretirement Benefit Plan Assets | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	158	158
Postretirement Benefit Plan Assets | Level 2 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	88	86
Postretirement Benefit Plan Assets | Level 2 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20	24
Postretirement Benefit Plan Assets | Level 2 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50	48
Postretirement Benefit Plan Assets | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Level 3 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Level 3 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Level 3 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Net Asset Value as a Practical Expedient
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Net Asset Value as a Practical Expedient | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Net Asset Value as a Practical Expedient | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Net Asset Value as a Practical Expedient | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 5	$ 4
Percentage of Plan Assets	5.00%	4.00%
Postretirement Benefit Plan Assets | Cash | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 3	$ 2
Percentage of Plan Assets	12.00%	7.00%
Postretirement Benefit Plan Assets | Cash | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 3	$ 3
Percentage of Plan Assets	2.00%	2.00%
Postretirement Benefit Plan Assets | Cash | Level 1 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 5	$ 4
Postretirement Benefit Plan Assets | Cash | Level 1 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	2
Postretirement Benefit Plan Assets | Cash | Level 1 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	3
Postretirement Benefit Plan Assets | Cash | Level 2 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Level 2 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Level 2 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Level 3 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Level 3 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Level 3 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Net Asset Value as a Practical Expedient | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Net Asset Value as a Practical Expedient | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Cash | Net Asset Value as a Practical Expedient | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. large cap | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 46	$ 46
Percentage of Plan Assets	35.00%	36.00%
Postretirement Benefit Plan Assets | U.S. large cap | Level 1 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 46	$ 46
Postretirement Benefit Plan Assets | U.S. large cap | Level 2 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. large cap | Level 3 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. large cap | Net Asset Value as a Practical Expedient | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | International | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 31	$ 30
Percentage of Plan Assets	24.00%	23.00%
Postretirement Benefit Plan Assets | International | Level 1 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 31	$ 30
Postretirement Benefit Plan Assets | International | Level 2 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | International | Level 3 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | International | Net Asset Value as a Practical Expedient | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 7	$ 7
Percentage of Plan Assets	7.00%	7.00%
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 2	$ 2
Percentage of Plan Assets	8.00%	7.00%
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1	$ 1
Percentage of Plan Assets	1.00%	1.00%
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 1 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 7	$ 7
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 1 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	2
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 1 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 2 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 2 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 2 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 3 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 3 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Level 3 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Net Asset Value as a Practical Expedient | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Net Asset Value as a Practical Expedient | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | U.S. Treasury securities and government bonds | Net Asset Value as a Practical Expedient | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Corporate bonds | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 85	$ 83
Percentage of Plan Assets	85.00%	86.00%
Postretirement Benefit Plan Assets | Corporate bonds | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 19	$ 23
Percentage of Plan Assets	76.00%	82.00%
Postretirement Benefit Plan Assets | Corporate bonds | Level 1 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Postretirement Benefit Plan Assets | Corporate bonds | Level 1 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Corporate bonds | Level 2 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	85	83
Postretirement Benefit Plan Assets | Corporate bonds | Level 2 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	19	23
Postretirement Benefit Plan Assets | Corporate bonds | Level 3 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Corporate bonds | Level 3 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Corporate bonds | Net Asset Value as a Practical Expedient | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Corporate bonds | Net Asset Value as a Practical Expedient | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Municipal bonds | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 3	$ 3
Percentage of Plan Assets	3.00%	3.00%
Postretirement Benefit Plan Assets | Municipal bonds | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1	$ 1
Percentage of Plan Assets	4.00%	4.00%
Postretirement Benefit Plan Assets | Municipal bonds | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 50	$ 48
Percentage of Plan Assets	38.00%	38.00%
Postretirement Benefit Plan Assets | Municipal bonds | Level 1 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Postretirement Benefit Plan Assets | Municipal bonds | Level 1 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Municipal bonds | Level 1 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Municipal bonds | Level 2 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	3
Postretirement Benefit Plan Assets | Municipal bonds | Level 2 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1
Postretirement Benefit Plan Assets | Municipal bonds | Level 2 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50	48
Postretirement Benefit Plan Assets | Municipal bonds | Level 3 | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Municipal bonds | Level 3 | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Municipal bonds | Level 3 | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Municipal bonds | Net Asset Value as a Practical Expedient | Bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Municipal bonds | Net Asset Value as a Practical Expedient | Active VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefit Plan Assets | Municipal bonds | Net Asset Value as a Practical Expedient | Non-bargained VEBA:
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

X

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (k)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (j)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (j)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (j)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (j)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
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