Number of Active Stock Plans

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Percentage of Company's match on Associate Stock Purchase Plan contributions

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- Definition

An entity may opt to disclose the lowest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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Share-based Compensation Arrangement by Share-based Payment Award, Number of Common Stock Trading Days Preceding the Vesting Date

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Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Target Number of Common Shares Granted

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Share-based Compensation Arrangement by Share-based Payment Award, Performance Period

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Share-based Compensation Arrangement by Share-based Payment Award, Potential Annual Reduction in Vesting Based on Performance, Percentage

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation Plans - Additional Information (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017 USD ($) plan $ / shares shares	Dec. 31, 2016 USD ($) $ / shares	Dec. 31, 2015 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of active stock plans \| plan		1
Shares authorized under plans (in shares) \| shares		55
Shares available for grant under plans (in shares) \| shares		15
Compensation expense from award		$ 244	$ 239	$ 161
Recognized tax benefit from stock-based compensation arrangements		$ 92	$ 89	$ 61
Percentage of company's match on Associate Stock Purchase Plan contributions by employees (percent)		17.65%
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares		$ 82.48	$ 62.89	$ 65.98
Amended and Restated 2004 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		$ 92	$ 31	$ 23
Amended and Restated 2004 Stock Incentive Plan \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum contractual term (Years)		10 years
Award vesting period (in years)		3 years
Weighted-average fair value of options granted (in dollars per share) \| $ / shares		$ 21.48	$ 16.36	$ 15.11
Unrecognized compensation expense related to unvested awards, options		$ 2
Weighted-average period of recognition of unrecognized compensation costs (Years)		9 months
Amended and Restated 2004 Stock Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		3 years
Total fair value of awards vested		$ 3	$ 21	$ 28
Unrecognized compensation expense related to unvested awards, awards other than options		$ 0
Amended and Restated 2004 Stock Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period of recognition of unrecognized compensation costs (Years)		1 year 8 months
Total fair value of awards vested		$ 110	$ 42	$ 27
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares		$ 86.20	$ 65.19	$ 76.15
Unrecognized compensation expense related to unvested awards, awards other than options		$ 116
Amended and Restated 2004 Stock Incentive Plan \| Performance Shares Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)		3 years
Weighted-average period of recognition of unrecognized compensation costs (Years)		1 year
Total fair value of awards vested		$ 1	$ 11	$ 30
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares		$ 0.00
Unrecognized compensation expense related to unvested awards, awards other than options		$ 0
Performance vesting period (in years)		3 years
Amended and Restated 2004 Stock Incentive Plan \| Performance Shares Awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential annual reduction in vesting based on performance (percent)		50.00%
Percentage of target award opportunities		0.00%
Amended and Restated 2004 Stock Incentive Plan \| Performance Shares Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential annual reduction in vesting based on performance (percent)		100.00%
Percentage of target award opportunities		150.00%
Amended and Restated 2004 Stock Incentive Plan \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of awards vested		$ 90	54	74
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares		$ 82.48
Unrecognized compensation expense related to unvested awards, awards other than options		$ 32
Amended and Restated 2004 Stock Incentive Plan \| Cash-Settled Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to unvested awards, awards other than options		0
Cash payments to settle awards		$ 42	36	70
Amended and Restated 2004 Stock Incentive Plan \| Cash-Settled Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock trading days required under vesting condition		15 days
Amended and Restated 2004 Stock Incentive Plan \| Cash-Settled Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock trading days required under vesting condition		20 days
Associate Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under plans (in shares) \| shares		33
Shares available for grant under plans (in shares) \| shares		18
Compensation expense from award		$ 23	$ 18	$ 16
Share Based Compensation Arrangement By Share Based Payment Award, Minimum Employee Subscription Rate		1.00%
Maximum percentage of monthly base pay eligible for the purchase plan		15.00%
Dividend Reinvestment Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under plans (in shares) \| shares		8
Shares available for grant under plans (in shares) \| shares		7
Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of company's match on Associate Stock Purchase Plan contributions by employees (percent)	15.00%