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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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 floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Shareholders' Equity (Stock Options Outstanding And Exercisable) (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Shares	19,237	20,461	23,637	25,610
Weighted Average Exercise Price (Per Share)	$ 28.71	$ 25.26	$ 22.58	$ 20.81
Weighted Average Remaining Contractual Life (Years)	5 years 8 months 27 days
Number of Shares	8,508	10,295	14,601
Weighted Average Exercise Price (Per Share)	$ 22.04
Exercise Price $14.62-16.48 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range	14.62
Upper range	$ 16.48
Number of Shares	3,513
Weighted Average Exercise Price (Per Share)	$ 15.23
Weighted Average Remaining Contractual Life (Years)	4 years 6 months 29 days
Number of Shares	2,396
Weighted Average Exercise Price (Per Share)	$ 14.97
Weighted Average Remaining Contractual Life (Years)	3 years 11 months 1 day
Exercise Price $17.65-21.05 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range	$ 17.65
Upper range	$ 21.05
Number of Shares	2,100
Weighted Average Exercise Price (Per Share)	$ 17.67
Weighted Average Remaining Contractual Life (Years)	4 years 11 days
Number of Shares	2,085
Weighted Average Exercise Price (Per Share)	$ 17.65
Weighted Average Remaining Contractual Life (Years)	4 years
Exercise Price $22.45-23.86 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range	$ 22.45
Upper range	$ 23.86
Number of Shares	4,028
Weighted Average Exercise Price (Per Share)	$ 23.20
Weighted Average Remaining Contractual Life (Years)	5 years 11 months 5 days
Number of Shares	1,678
Weighted Average Exercise Price (Per Share)	$ 23.20
Weighted Average Remaining Contractual Life (Years)	5 years 11 months 5 days
Exercise Price $27.03-36.16 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range	$ 27.03
Upper range	$ 36.16
Number of Shares	5,515
Weighted Average Exercise Price (Per Share)	$ 32.08
Weighted Average Remaining Contractual Life (Years)	4 years 2 months 23 days
Number of Shares	2,349
Weighted Average Exercise Price (Per Share)	$ 32.32
Weighted Average Remaining Contractual Life (Years)	4 years 8 months 5 days
Exercise Price $40.64-53.34 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range	$ 40.64
Upper range	$ 53.34
Number of Shares	4,081
Weighted Average Exercise Price (Per Share)	$ 46.88
Weighted Average Remaining Contractual Life (Years)	9 years 5 months 27 days
Number of Shares	0
Weighted Average Exercise Price (Per Share)	$ 0.00