Income Taxes (Summary Of Detail Of Tax Carryforwards) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Income Tax Contingency [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	$ 31	$ 40
Operating Loss Carryforwards, Valuation Allowance	(19)	(21)
Deferred Tax Assets, Net of Valuation Allowance	1,637	$ 1,802
Total Net Operating Losses [Member]
Income Tax Contingency [Line Items]
Deferred Tax Assets, Net of Valuation Allowance	12
Net Operating Losses Federal Date Range 2
Income Tax Contingency [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, Domestic	9
Operating Loss Carryforwards, Valuation Allowance	0
Deferred Tax Assets, Net of Valuation Allowance	9
Net Operating Losses States Date Range One [Member]
Income Tax Contingency [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	13
Operating Loss Carryforwards, Valuation Allowance	(13)
Deferred Tax Assets, Net of Valuation Allowance	0
Net Operating Losses States Date Range Two [Member]
Income Tax Contingency [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	3
Operating Loss Carryforwards, Valuation Allowance	(2)
Deferred Tax Assets, Net of Valuation Allowance	1
Net Operating Losses States Date Range Three [Member]
Income Tax Contingency [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	3
Operating Loss Carryforwards, Valuation Allowance	(2)
Deferred Tax Assets, Net of Valuation Allowance	1
Other Credits States Date Range One [Member]
Income Tax Contingency [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	3
Operating Loss Carryforwards, Valuation Allowance	(2)
Deferred Tax Assets, Net of Valuation Allowance	$ 1

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

+ References

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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-Section 50
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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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.

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