No definition available.

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Number of employees holding share based payment awards at the reporting date.

+ References

No definition available.

+ Details

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- Definition

The percent of the original grant amount that holders of strategic performance shares will be awarded in shares of the Company's common stock at the end of the performance period.

+ References

No definition available.

+ Details

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- Definition

Percent of executive strategic performance shares that are subject to a market condition - total shareholder return relative to industry peer companies

+ References

No definition available.

+ Details

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- Definition

Percent of executive strategic performance shares that are subject to a performance condition - revenue growth and cumulative adjusted net income

+ References

No definition available.

+ Details

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The period of time which a traded option of the reporting entity might be outstanding. The volatility of traded options is not used as a component of the expectedvolatility of outstanding share based compensation option awards as the term of these options does not correlate to the expected term of share-based option awards.

+ References

No definition available.

+ Details

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The period of time over which performance is measured to determine achievement for the performance awards.

+ References

No definition available.

+ Details

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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
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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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No definition available.

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- References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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Unrecognized cost of unvested share-based compensation awards.

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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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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 2
-Subparagraph (h)(1)(i)
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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ References

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- References

No definition available.

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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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
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- Definition

The number of grants made 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ 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 (c)(2)(i)-(ii)
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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.

+ Details

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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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.

+ Details

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ 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 (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Data Type:	xbrli:sharesItemType
Balance Type:	na
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- Definition

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.

+ 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 (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ 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 (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
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- Definition

The estimated measure of the 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (f)(2)(ii)
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (f)(2)(iv)
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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.

+ References

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (c)(1)(iii)
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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 2
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section 50
-Paragraph 2
-Subparagraph (d)(2)
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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)-(4)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average price of options that were either forfeited or expired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(1)(iv)(3)-(4)
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- Definition

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

+ References

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Employee Incentive Plans (Details) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) Employees $ / shares shares	Dec. 31, 2014 $ / shares shares	Dec. 31, 2013 $ / shares shares
Employee Incentive Plans [Abstract]
Compensation costs \| $	$ 111	$ 101	$ 88
Tax benefits \| $	$ 24	$ 12	$ 25
Number of shares of common stock available for award \| shares				8,600	10,300	13,200
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding - January 1 \| shares	7,331	7,350	8,951
Options Granted \| shares	1,410	2,012	1,890
Options Exercised \| shares	(2,146)	(1,869)	(3,107)
Options Expired or canceled \| shares	(162)	(162)	(384)
Options outstanding - December 31 \| shares	6,433	7,331	7,350
Options Exercisable - Number (in thousands) \| shares				3,414	3,919	4,217
Share Based Compensation Arrangement By Share Based Payment Award, Options Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price - Options Outstanding - January 1 \| $ / shares	$ 51.84	$ 42.24	$ 36.29
Weighted Average Exercise Price - Options Granted \| $ / shares	120.94	78.11	58.84
Weighted Average Exercise Price - Options Exercised \| $ / shares	43.63	41.29	34.99
Weighted Average Exercise Price - Options Expired or canceled \| $ / shares	86.04	64.27	43.86
Weighted Average Exercise Price - Options Outstanding - December 31 \| $ / shares	$ 68.86	$ 51.84	$ 42.24
Options Exercisable - Weighted Average Exercise Price \| $ / shares				$ 46.55	$ 38.11	$ 35.84
Information For Stock Options Exercised Details [Abstract]
Intrinsic value of options exercised \| $	$ 179	$ 84	$ 105
Cash received for options exercised \| $	94	76	109
Excess tax benefits realized from options exercised \| $	$ 33	$ 19	$ 23
Information for Outstanding Common Stock Options [Abstract]
Options Outstanding - Number (in thousands) \| shares	6,433	7,331	8,951	6,433	7,331	7,350
Options Outstanding - Total intrinsic value \| $				$ 498
Options Outstanding - Weighted Average Exercise Price \| $ / shares	$ 51.84	$ 51.84	$ 36.29	$ 68.86	$ 51.84	$ 42.24
Options Outstanding - Weighted average remaining contractual life	6 years 9 months 18 days
Options Exercisable - Number (in thousands) \| shares				3,414	3,919	4,217
Options Exercisable - Total Intrinsic Value \| $				$ 341
Options Exercisable - Weighted Average Exercise Price \| $ / shares				$ 46.55	$ 38.11	$ 35.84
Options Exercisable - Weighted Average Remaining Contractual Life	5 years 4 months 24 days
Assumptions For Fair Value of Options Granted Details [Abstract]
Dividend Yield	0.00%	0.10%	0.10%
Expected Volatility	35.00%	35.00%	40.00%
Risk-free Interest Rate	1.30%	1.30%	0.70%
Expected Option Life	4 years 3 months 18 days	4 years 3 months 18 days	4 years 6 months
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Compensation expense related to non-vested share-based awards \| $				$ 36
Period in which compensation expense will be recognized	2 years
Weighted average fair value of options granted under employee incentive plans \| $ / shares	$ 36.40	$ 23.56	$ 19.84
Employee Stock Option [Member] \| Minimum [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Award vesting period	1 year
Employee Stock Option [Member] \| Maximum [Member]
Assumptions For Fair Value of Options Granted Details [Abstract]
Remaining maturity of traded options	1 year
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Award vesting period	5 years
Award expiration period	10 years
Restricted Stock Grants And Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Nonvested, Roll Forward
Outstanding - January 1 \| shares	2,121	2,844	4,064
Awarded \| shares	352	454	525
Vested \| shares	(736)	(1,065)	(1,480)
Forfeited \| shares	(95)	(112)	(265)
Outstanding - December 31 \| shares	1,642	2,121	2,844
Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding - January 1 \| $ / shares	$ 53.59	$ 41.56	$ 35.00
Awarded \| $ / shares	121.93	78.99	59.36
Vested \| $ / shares	41.99	32.34	30.24
Forfeited \| $ / shares	68.31	52.95	39.46
Outstanding - December 31 \| $ / shares	$ 72.58	$ 53.59	$ 41.56
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Fair value of vested equity-based awards \| $	$ 92	$ 85	$ 94
Number of employees holding share based payment awards at the reporting date. \| Employees				3,900
Compensation expense related to non-vested share-based awards \| $				$ 56
Period in which compensation expense will be recognized	2 years
Strategic Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Nonvested, Roll Forward
Outstanding - January 1 \| shares	1,547	1,572	1,600
Awarded \| shares	311	450	616
Vested \| shares	(608)	(397)	(448)
Forfeited \| shares	(62)	(78)	(196)
Outstanding - December 31 \| shares	1,188	1,547	1,572
Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding - January 1 \| $ / shares	$ 59.20	$ 49.67	$ 41.92
Awarded \| $ / shares	121.78	78.50	59.84
Vested \| $ / shares	45.51	43.53	36.88
Forfeited \| $ / shares	76.33	58.41	47.52
Outstanding - December 31 \| $ / shares	$ 81.68	$ 59.20	$ 49.67
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Performance period for strategic performance shares	3 years
Fair value of vested equity-based awards \| $	$ 119	$ 57	$ 42
Strategic Performance Shares Subject to Market Conditions	50.00%
Strategic Performance Shares Subject to Performance Conditions	50.00%
Number of employees holding share based payment awards at the reporting date. \| Employees				1,300
Compensation expense related to non-vested share-based awards \| $				$ 37
Period in which compensation expense will be recognized	2 years
Strategic Performance Shares [Member] \| Minimum [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Percent of original grant awarded at end of performance period				0.00%
Strategic Performance Shares [Member] \| Maximum [Member]
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Percent of original grant awarded at end of performance period				200.00%