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
-Paragraph 2
-Subparagraph (c)(1)(iii)
-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.

+ 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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

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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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

No definition available.

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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.

+ 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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Share-Based Compensation (Schedule Of Additional Selected Information On Stock Options) (Details) - $ / shares			12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding stock options, Number of shares	3,804,095	5,630,502	3,437,910	5,874,590
Outstanding stock options, Weighted average exercise price	$ 27.30	$ 31.60	$ 26.44	$ 35.54
Outstanding stock options, Weighted average remaining contractual life (years)	3 years	3 years 36 days	4 years 1 month 12 days
Exercisable stock options, Number of shares	2,187,259	3,804,873	1,892,136
Exercisable stock options, Weighted average exercise price	$ 26.35	$ 33.86	$ 27.60
Exercise Price Range $0.32 To $19.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding stock options, Number of shares			277,859
Outstanding stock options, Weighted average exercise price			$ 17.81
Outstanding stock options, Weighted average remaining contractual life (years)			2 years 5 months
Exercisable stock options, Number of shares			277,859
Exercisable stock options, Weighted average exercise price			$ 17.81
Exercise Price Range $20.00 To $24.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding stock options, Number of shares			1,121,039
Outstanding stock options, Weighted average exercise price			$ 21.97
Outstanding stock options, Weighted average remaining contractual life (years)			4 years 5 months
Exercisable stock options, Number of shares			382,396
Exercisable stock options, Weighted average exercise price			$ 23.84
Exercise Price Range $25.00 To $29.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding stock options, Number of shares			1,877,880
Outstanding stock options, Weighted average exercise price			$ 28.35
Outstanding stock options, Weighted average remaining contractual life (years)			4 years 5 months
Exercisable stock options, Number of shares			1,088,210
Exercisable stock options, Weighted average exercise price			$ 28.14
Exercise Price Range $30.00 To $39.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding stock options, Number of shares			52,379
Outstanding stock options, Weighted average exercise price			$ 30.10
Outstanding stock options, Weighted average remaining contractual life (years)			3 years 4 months
Exercisable stock options, Number of shares			34,918
Exercisable stock options, Weighted average exercise price			$ 30.10
Exercise Price Range $45.00 To $49.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding stock options, Number of shares			70,200
Outstanding stock options, Weighted average exercise price			$ 47.10
Outstanding stock options, Weighted average remaining contractual life (years)			1 year 2 months 24 days
Exercisable stock options, Number of shares			70,200
Exercisable stock options, Weighted average exercise price			$ 47.10
Exercise Price Range $60.00 To $79.99 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding stock options, Number of shares			2,553
Outstanding stock options, Weighted average exercise price			$ 72.08
Outstanding stock options, Weighted average remaining contractual life (years)			1 month 15 days
Exercisable stock options, Number of shares			2,553
Exercisable stock options, Weighted average exercise price			$ 72.08
Exercise Price Range $82.00 To $83.38 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding stock options, Number of shares			36,000
Outstanding stock options, Weighted average exercise price			$ 83.38
Outstanding stock options, Weighted average remaining contractual life (years)			4 months 18 days
Exercisable stock options, Number of shares			36,000
Exercisable stock options, Weighted average exercise price			$ 83.38