The stock price per share on the grant date for issuance to employees under the plan.

No definition available.

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- Definition

Represents the minimum term of service to meet the criteria for a Long Service Separation.

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No definition available.

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Represents the required minimum age of a participant upon separation from service to meet the criteria for a Long Service Separation.

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No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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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

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).

+ References

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- References

No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

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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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No definition available.

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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- Definition

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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- Definition

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

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No definition available.

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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

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Stock-based compensation awards
Required minimum age of a participant upon separation from service to meet the criteria for Long Service Separation (in years)	55 years
Minimum term of service to meet criteria for Long Service Separation (in years)	5 years
Original number of common shares reserved for future issuance					38,800,000
Additional number of common shares reserved for future issuance	36,000,000
Stock-based compensation expense, before tax (in dollars)	$ 68	$ 45	$ 117	$ 146
Assumptions used in determining the fair value of the stock-based awards
Weighted-average dividend yield (as a percent)			3.42%	3.23%
Weighted-average volatility (as a percent)			29.20%	31.10%
Volatilities, low end of range (as a percent)			22.10%	22.50%
Volatilities, high end of range (as a percent)			33.00%	33.40%
Risk-free interest rates, low end of range (as a percent)			0.81%	0.62%
Risk-free interest rates, high end of range (as a percent)			2.35%	1.73%
Weighted-average expected lives (in years)			8 years	8 years
Unrecognized compensation cost related to nonvested stock-based compensation awards (in dollars)	$ 236		$ 236
Term of amortization of unrecognized compensation cost over weighted-average remaining requisite service periods (in years)			1 year 8 months
Stock Options
Stock-based compensation awards
Shares Granted (in shares)			2,701,644	4,243,272
Weighted-Average Fair Value Per Share (in dollars per share)			$ 25.01	$ 20.64
Weighted-Average Grant Date Stock Price (in dollars per share)	$ 95.66	$ 74.77	95.66	74.77
RSUs
Stock-based compensation awards
Weighted-Average Grant Date Stock Price (in dollars per share)	95.63	74.77	$ 95.63	$ 74.77
Shares Granted (in shares)			906,068	1,085,505
Weighted-Average Fair Value Per Share (in dollars per share)			$ 89.76	$ 68.04
PRSUs
Stock-based compensation awards
Weighted-Average Grant Date Stock Price (in dollars per share)	$ 95.66	$ 74.77	$ 95.66	$ 74.77
Shares Granted (in shares)			437,385	614,347
Weighted-Average Fair Value Per Share (in dollars per share)			$ 86.78	$ 64.71