Income tax benefits due to inflation reduction act tax credits.

No definition available.

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- Definition

Income tax benefits recorded in cost of goods sold.

+ References

No definition available.

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- Definition

Income taxes.

+ References

No definition available.

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- Definition

Received income tax benefit including interest income from prior tax credit.

+ References

No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
-Section S50
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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Mar. 31, 2026	Dec. 31, 2025
Income Taxes [Line Items]
Effective federal statutory tax rate				21.00%
Received income tax benefit including interest income from prior tax credit	$ 36
Foreign [Member] \| Manicouagan Power Limited Partnership [Member]
Income Taxes [Line Items]
Deferred tax assets, valuation allowance						$ 22
Cost of Goods Sold [Member]
Income Taxes [Line Items]
Income tax benefits recorded in Cost of goods sold		$ 18	$ 17	$ 31	$ 31
Other Receivables [Member]
Income Taxes [Line Items]
Income tax benefits due to inflation reduction act tax credits	56	56		56			$ 90
Other Noncurrent Assets [Member]
Income Taxes [Line Items]
Income tax benefits due to inflation reduction act tax credits	$ 112	$ 112		$ 112			$ 83