A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The weighted average grant date fair value of options and equity instruments other than options issued during the period, including both vested and nonvested instruments.

+ References

No definition available.

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- Definition

Number of options and equity Instruments other than options outstanding, including both vested and non-vested instruments.

+ References

No definition available.

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- Definition

The weighted average grant date fair value of options and equity instruments other than options settled during the period.

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Option and Non-Option Equity Instruments, Outstanding [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Number of option and non-option equity instruments exercised by participants.

+ References

No definition available.

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- Definition

Number of shares under option and non-option equity instrument agreements that were either cancelled or expired.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans including option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

No definition available.

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- Definition

Weighted average fair value as of the grant date of stock options and non-option equity instruments that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

No definition available.

+ Details

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- Definition

Weighted average remaining contractual term for option and non-option equity-based awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The total fair value of options and non-option equity instruments that vested during the period.

+ References

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=96867065&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=96867065&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

+ Details

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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.

+ References

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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.

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

+ References

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- Definition

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

+ References

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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.

+ References

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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=96867065&loc=d3e5070-113901

Reference 2: 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.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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Stock Incentive Plans (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
Stock Incentive Awards Units Outstanding (Roll Forward)
Units outstanding at beginning of period (in shares)	55.1
Granted (in shares)	16.7
Settled (in shares)	(16.3)
Forfeited or expired (in shares)	(2.6)
Units outstanding at end of period (in shares)	52.9	55.1
Stock Incentive Awards Weighted Average Grant Date Fair Value (Per Share) [Roll Forward]
Weighted-average grant date fair value, Units outstanding at beginning of period (in dollars per share)	$ 19.77
Weighted-average grant date fair value, granted (in dollars per share)	26.75
Weighted-average grant date fair value, settled (in dollars per share)	24.65
Weighted-average grant date fair value, forfeited or expired (in dollars per share)	26.67
Weighted-average grant date fair value, Units outstanding at end of period (in dollars per share)	$ 19.77	$ 19.77		$ 21.75
Remaining Contractual Term [Abstract]
Weighted Average Remaining Contractual Terms in years, Outstanding	2 years	2 years 6 months
Compensation expense	$ 585	$ 627	$ 422
Unrecognized compensation expense				$ 278
Weighted-average period for total unrecognized compensation expense for nonvested equity awards	1 year 8 months 12 days
Fair value of stock incentive awards vested	$ 421	$ 325	$ 228
Restricted Stock Units (RSUs) [Member]
Stock Incentive Plans Narratives [Abstract]
Service period	3 years
Performance Share Units (PSUs) [Member]
Stock Incentive Plans Narratives [Abstract]
Performance period	3 years
Stock options [Member]
Stock Incentive Plans Narratives [Abstract]
Expiration period	10 years
Remaining Contractual Term [Abstract]
Dividend yield	4.43%		4.60%
Expected volatility	25.00%		26.10%
Risk-free interest rate	1.97%		2.00%
Expected option life	5 years 10 months 2 days		6 years 7 months 2 days
Performance-based Employee Stock Options [Member]
Stock Incentive Plans Narratives [Abstract]
Service period	55 months
Service-based Employee Stock Options [Member] \| Minimum [Member]
Stock Incentive Plans Narratives [Abstract]
Service period	19 months
Service-based Employee Stock Options [Member] \| Maximum [Member]
Stock Incentive Plans Narratives [Abstract]
Service period	3 years
Restricted Stock Awards (RSAs) [Member]
Stock Incentive Plans Narratives [Abstract]
Service period	3 years