Consolidated Statements of Shareholders' Equity (Parenthetical) (Unaudited) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Statement Of Stockholders Equity [Abstract]
Net (losses) gains arising during the period, tax	$ (1)	$ 6	$ 4	$ (6)
Reclassification adjustment for losses (gains) included in net loss, tax	(2)	0	0	(3)
Change in unrecognized gains (losses) and prior service cost related to pension and other post-retirement benefit plans, tax	$ 0	$ 0	$ (1)	$ 0

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (j)
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (k)
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-URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
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-Topic 220
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 810
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-10A

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