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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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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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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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

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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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.

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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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Shareholders' Equity (Stock Options Outstanding And Exercisable) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Shares	20,461	23,637	25,610	27,043
Weighted Average Exercise Price (Per Share)	$ 25.26	$ 22.58	$ 20.81	$ 20.06
Weighted Average Remaining Contractual Life (Years)	5 years 9 months 15 days
Number of Shares	10,295	14,601	9,760
Weighted Average Exercise Price (Per Share)	$ 20.58
Exercise Price $14.62-15.77 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range	$ 14.62
Upper range	$ 15.77
Number of Shares	4,073
Weighted Average Exercise Price (Per Share)	$ 15.19
Weighted Average Remaining Contractual Life (Years)	5 years 5 months 23 days
Number of Shares	2,915
Weighted Average Exercise Price (Per Share)	$ 14.95
Weighted Average Remaining Contractual Life (Years)	5 years 8 months 9 days
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	3,534
Weighted Average Exercise Price (Per Share)	$ 18.20
Weighted Average Remaining Contractual Life (Years)	3 years 8 months 16 days
Number of Shares	3,519
Weighted Average Exercise Price (Per Share)	$ 18.27
Weighted Average Remaining Contractual Life (Years)	4 years 5 months 27 days
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	4,399
Weighted Average Exercise Price (Per Share)	$ 23.20
Weighted Average Remaining Contractual Life (Years)	6 years 11 months 5 days
Number of Shares	1,960
Weighted Average Exercise Price (Per Share)	$ 21.92
Weighted Average Remaining Contractual Life (Years)	4 years 4 months 6 days
Exercise Price $27.03-32.49 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range	$ 27.03
Upper range	$ 32.49
Number of Shares	4,073
Weighted Average Exercise Price (Per Share)	$ 30.95
Weighted Average Remaining Contractual Life (Years)	2 years 8 months 5 days
Number of Shares	1,901
Weighted Average Exercise Price (Per Share)	$ 26.57
Weighted Average Remaining Contractual Life (Years)	5 years 1 month 2 days
Exercise Price $33.73-40.64 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range	$ 33.73
Upper range	$ 40.64
Number of Shares	4,382
Weighted Average Exercise Price (Per Share)	$ 37.10
Weighted Average Remaining Contractual Life (Years)	9 years 6 months
Number of Shares	0
Weighted Average Exercise Price (Per Share)	$ 31.17
Weighted Average Remaining Contractual Life (Years)	4 years