Income Taxes (Components Of Income From Continuing Operations) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	$ (35)	$ (1,051)	$ (141)
Income (Loss) from Continuing Operations before Income Taxes, Foreign	347	274	441
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	312	(777)	300
UNITED KINGDOM
Operating Loss Carryforwards [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Foreign	105	130	162
AUSTRALIA
Operating Loss Carryforwards [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Foreign	32	180	280
CANADA
Operating Loss Carryforwards [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Foreign	87	(101)	(117)
International [Member]
Operating Loss Carryforwards [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Foreign	$ 123	$ 65	$ 116

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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