Change in discount rate assumption.

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The amount of cash issued to participants as the employers' matching contribution to the Company's 401(k) plan.

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Defined Benefit Plan, Actual Return on Plan Assets Sold During Period, Number of Shares

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- Definition

Defined Benefit Plan Assumptions Used In Calculations

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Defined benefit plan shares sold related to entity, gain.

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- Definition

Age at which participants could elect to remain in the defined benefit plan as of August 31, 2008.

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Defined Benefit Plan, Total Recognized in Net Periodic Benefit Costs and Other Comprehensive Income, before Tax

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Defined Contribution Plan Matching Percent Of Compensation

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- Definition

Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

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- Definition

The amounts in accumulated other comprehensive income related to gains and losses that are not recognized immediately and are expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

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- Definition

The amounts in accumulated other comprehensive income related to prior service cost or credit expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

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- Definition

The amount of employer securities or securities of parties related to the employer that are included in plan assets.

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

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- Definition

The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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The number of employer shares or related party shares included in plan assets.

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

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Equity impact of common stock cash dividends declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Name Accounting Standards Codification

-Topic 505

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-Section S99

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Employee Retirement Benefits (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2008
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Minimum participant age to elect				40 years
Payment for terminated vested participants	$ 15	$ 19
Matching contributions for 401(k) plan	9	8	8
Pension plan assumptions	100.00%
Total recognized in net periodic benefit cost and other comprehensive income	31	38	9
Amortization of actuarial loss	8
Amortization of prior service cost	1
Pension plan assets at fair value	238	216	183
Cash dividends paid	263	261	259
Domestic Equity Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	75.00%
Domestic Equity Securities [Member] \| Information Technology Sector [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	19.00%
Domestic Equity Securities [Member] \| Financial Services Sector [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	22.00%
Domestic Equity Securities [Member] \| Healthcare Sector [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	13.00%
Domestic Equity Securities [Member] \| Industrial Sector [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	11.00%
Domestic Equity Securities [Member] \| Consumer Discretionary Sector [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	10.00%
Domestic Equity Securities [Member] \| All Remaining Sectors [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	10.00%
States, Municipalities And Political Subdivisions [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	15.00%
Domestic Corporate Debt Securities [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Allocation percentage of investments	10.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension plan assets at fair value	3
Terminated Vested Participants
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Payment for terminated vested participants	2	9
Maximum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Matching contribution to defined contribution plan	6.00%
Percentage of return on plan assets			8.00%
Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of return on plan assets		7.50%
Qualified Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension plan assets, shares	567,113
Pension plan assets, fair value	22	17
Pension plan assets, sold shares		75,000
Pension plan assets, entity's shares sold, gain		2
Cash dividends paid	1	1
Expected contribution by employer during 2013	15
Qualified Pension Plan [Member] \| Benefit Obligations [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of decrease in discount rate	0.90%
Qualified Pension Plan [Member] \| Net Periodic Benefit Costs [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of decrease in discount rate	0.75%
Supplemental Executive Retirement Plan (SERP) [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accrued employee benefit	9	8
Expected contribution by employer during 2013	$ 3
Supplemental Executive Retirement Plan (SERP) [Member] \| Benefit Obligations [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of decrease in discount rate	0.80%
Supplemental Executive Retirement Plan (SERP) [Member] \| Net Periodic Benefit Costs [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of decrease in discount rate	0.80%