Stock-Based Compensation (Summary Of Changes Of Stock Options) (Details) (USD $) In Millions, except Per Share data	6 Months Ended	12 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Stock-Based Compensation
Outstanding at December 31, 2010, Shares	16.3
Granted, Shares	0.8
Forfeited / expired, Shares	(1.0)
Outstanding at June 30, 2011, Shares	16.1	16.3
Outstanding at December 31, 2010, Weighted Average Exercise Price	$ 22
Granted, Weighted Average Exercise Price	$ 20
Forfeited / expired, Weighted Average Exercise Price	$ 22
Outstanding at June 30, 2011, Weighted Average Exercise Price	$ 21	$ 22
Outstanding at December 31, 2010, Exercisable at Period End	8.9
Outstanding at June 30, 2011, Exercisable at Period End	9.4	8.9
Outstanding at period end, Aggregate Intrinsic Value Exercisable	$ 0.4	$ 1.5

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance-sheet date.

+ Details

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance-sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(c), d(2)

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ Details

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- Definition

For presentations that combine terminations, the weighted average price of expired options and the price at which grantees could have acquired the underlying shares with respect to stock options that were terminated during the reporting period due to noncompliance with plan terms during the reporting period .

+ Details

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- Definition

The quantity of shares issuable on stock options awarded under the plan during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(d)

+ Details

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- Definition

The weighted average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(d)

+ Details

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance-sheet date, including vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(a)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(b)

+ Details

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- Definition

The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(a)

+ Details

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