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.

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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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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://fasb.org/us-gaap/role/ref/legacyRef
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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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No definition available.

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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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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, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of options outstanding (in shares)	18,495	15,706	15,813	16,712
Options outstanding, weighted average exercise price (in USD per share)	$ 51.15	$ 47.43	$ 41.84	$ 37.63
Options outstanding weighted average remaining contractual life, years	6 years 10 months 24 days
Number of options exercisable (in shares)	6,641	8,214
Exercisable shares, weighted avg. price (in USD per share)	$ 39.35
Exercise Price $14.62-21.05
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Lower range (in USD per share)	15.77
Upper range (in USD per share)	$ 21.05
Number of options outstanding (in shares)	665
Options outstanding, weighted average exercise price (in USD per share)	$ 15.79
Options outstanding weighted average remaining contractual life, years	11 months 12 days
Number of options exercisable (in shares)	665
Exercisable shares, weighted avg. price (in USD per share)	$ 15.79
Options exercisable, weighted average remaining contractual life, years	11 months 12 days
Exercise Price $22.45-23.86
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Lower range (in USD per share)	$ 22.45
Upper range (in USD per share)	$ 23.86
Number of options outstanding (in shares)	944
Options outstanding, weighted average exercise price (in USD per share)	$ 22.45
Options outstanding weighted average remaining contractual life, years	1 year 11 months 12 days
Number of options exercisable (in shares)	944
Exercisable shares, weighted avg. price (in USD per share)	$ 22.45
Options exercisable, weighted average remaining contractual life, years	1 year 11 months 12 days
Exercise Price $27.03-40.64
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Lower range (in USD per share)	$ 27.03
Upper range (in USD per share)	$ 40.64
Number of options outstanding (in shares)	2,699
Options outstanding, weighted average exercise price (in USD per share)	$ 37.35
Options outstanding weighted average remaining contractual life, years	3 years 5 months 26 days
Number of options exercisable (in shares)	1,857
Exercisable shares, weighted avg. price (in USD per share)	$ 35.85
Options exercisable, weighted average remaining contractual life, years	3 years 3 months 14 days
Exercise Price $45.99-53.16
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Lower range (in USD per share)	$ 45.99
Upper range (in USD per share)	$ 56.60
Number of options outstanding (in shares)	8,398
Options outstanding, weighted average exercise price (in USD per share)	$ 62.57
Options outstanding weighted average remaining contractual life, years	8 years 1 month 2 days
Number of options exercisable (in shares)	3,170
Exercisable shares, weighted avg. price (in USD per share)	$ 51.34
Options exercisable, weighted average remaining contractual life, years	5 years 6 months 10 days
Exercise Price $53.34-71.12
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Lower range (in USD per share)	$ 57.48
Upper range (in USD per share)	$ 71.12
Number of options outstanding (in shares)	5,789
Options outstanding, weighted average exercise price (in USD per share)	$ 49.76
Options outstanding weighted average remaining contractual life, years	8 years 29 days
Number of options exercisable (in shares)	5
Exercisable shares, weighted avg. price (in USD per share)	$ 63.50
Options exercisable, weighted average remaining contractual life, years	6 years 9 months 25 days