v2.4.0.6

Retirement Plans (Schedule Of Expense Related To These Defined Contribution Plans) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expense related to defined contribution plans | $ 54 | $ 49 | $ 49
401 (k) Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expense related to defined contribution plans | 33 | 32 | 34
Canadian Pension And Savings Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Expense related to defined contribution plans | $ 21 | $ 17 | $ 15

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- Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 11 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
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