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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Net number of share options (or share units) granted during the period.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Stock Based Compensation - Stock Options (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Share Based Compensation Arrangement By Share Based Payment Award Options Expiration Term	10 years
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options	$ 2	$ 1	$ 1
Share - Based Compensation Arrangement By Share - Based Payment Award Options Vested Aggregate Intrinsic Value	2
Share Based Compensation Arrangement By Share Based Payment Award Options Expected To Vest Intrinsic Value	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	3	1	3
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	2,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 20.01
Share Based Compensation Arrangement By Share Based Payment Award Grant Date Fair Value Of Options	$ 9	$ 6	$ 7
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	1,789,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	1,750,000
Stock Options Fiscal 2004 Plan [Member] \| Stock Option [Member]
Schedule of Options Rollfoward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	1,789,000	2,052,000	2,264,000	2,681,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(263,000)	(68,000)	(219,000)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period	0	(144,000)	(54,000)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	0	0	(144,000)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	1,750,000	1,469,000	1,354,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	2,395,000	3,282,000	4,082,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 20.01	$ 18.24	$ 18.04	$ 18.83
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 0.00	$ 0.00	$ 0.00
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 6.21	$ 5.93	$ 6.30
Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price	$ 0.00	$ 20.84	$ 22.41
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price	$ 0.00	$ 0.00	$ 23.04
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 19.90	$ 17.09	$ 15.97
Stock Option Plan 1995 [Member] \| Stock Option [Member]
Schedule of Options Rollfoward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			70,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price			$ 3.06
Minimum [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights	P3Y
Maximum [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights	P5Y
Range 1 [Member]
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 5,930,000
Range 1 [Member] \| Stock Option [Member]
Schedule of Options Rollfoward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 5.93
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	76,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	1 year 9 months 18 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	76,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 5.93
Range 2 [Member]
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 11,400,000
Range 2 [Member] \| Stock Option [Member]
Schedule of Options Rollfoward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 11.40
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	80,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	2 years 8 months 12 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	80,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 11.40
Range 3 [Member]
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 0
Range 3 [Member] \| Stock Option [Member]
Schedule of Options Rollfoward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 20.52
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	1,403,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	4 years 2 months 12 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	1,403,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 20.52
Range 4 [Member] \| Stock Option [Member]
Schedule of Options Rollfoward [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 24.57
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	230,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	5 years 4 months 24 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	191,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 24.53
Range 4 [Member] \| Minimum [Member]
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 0
Range 4 [Member] \| Maximum [Member]
Disclosure Options For Shares In Price Ranges [Abstract]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 26,840,000