Income Taxes - Deferred Tax Assets and Valuation Allowances (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Deferred tax assets and valuation allowances:
Net operating loss, deferred tax assets	$ 1,416	$ 2,024
Tax credits, deferred tax assets	312	$ 300
General Business Credits \| Expires from 2036 - 2044
Deferred tax assets and valuation allowances:
Tax credits, unused amount	312
Tax credits, deferred tax assets	312
Tax credits, valuation allowance	0
U.S. Federal \| Indefinite Tax Period
Deferred tax assets and valuation allowances:
Net operating loss, unused amount	5,707
Net operating loss, deferred tax assets	1,198
Net operating loss, valuation allowance	0
State \| Expires from 2024 - 2044
Deferred tax assets and valuation allowances:
Net operating loss, unused amount	4,560
Net operating loss, deferred tax assets	194
Net operating loss, valuation allowance	(40)
Foreign \| Indefinite Tax Period
Deferred tax assets and valuation allowances:
Net operating loss, unused amount	70
Net operating loss, deferred tax assets	24
Net operating loss, valuation allowance	$ (24)

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-3

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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

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