Description Of Company And Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
New Accounting Pronouncement, Early Adoption [Line Items]
Intangibles not subject to amortization	$ 11	$ 11
Period In Years That Unrecognized Actuarial Net Gains (Losses) Are Being Recognized		15 years
Finite lived intangible assets useful lives	25 years
Restricted cash and cash equivalents	$ 2	$ 17
ASU 2015-17 [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Deferred Tax Assets, Net of Valuation Allowance, Current		90
Deferred Tax Liabilities, Net, Current		$ 46

Period In Years That Unrecognized Actuarial Net Gains (Losses) Are Being Recognized

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- Definition

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards expected to be realized or consumed within one year or operating cycle, if longer.

+ References

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- Definition

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, netted by jurisdiction and classified as current.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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- 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.

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