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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 or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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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.

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

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No definition available.

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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No definition available.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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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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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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Number of share options (or share units) exercised during the current period.

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Share-Based Compensation (Schedule Of Stock Option Activity) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Number of Shares
Options outstanding, beginning (in shares)	1,652,505	1,033,838	1,004,014
Options outstanding, December 31 (in shares)	2,216,175	1,652,505	1,033,838
Options exercisable, December 31 (in shares)	1,701,155
Weighted Average Grant Date Fair Value
Outstanding, January 1 (in usd per share)	$ 78.10	$ 83.54	$ 74.35
Outstanding, December 31 (in usd per share)	70.97	$ 78.10	$ 83.54
Exercisable, December 31 (in usd per share)	$ 74.78
Weighted Average Remaining Contractual Life (Years)
Options outstanding, December 31, 2022	2 years 9 months 21 days
Exercisable at December 31, 2022	2 years 6 months
2012 Plan
Number of Shares
Options granted (in shares)		12,500	319,669
Options exercised (in shares)		(20,000)	(512,509)
Options forfeited (in shares)	(23,000)		(16,669)
Weighted Average Grant Date Fair Value
Granted (in usd per share)		$ 69.20	$ 90.79
Exercised (in usd per share)		$ 60.52	72.98
Forfeited (in usd per share)	$ 62.33		$ 81.37
2019 Stock Option Plan
Number of Shares
Options granted (in shares)	718,000	639,500	272,331
Options exercised (in shares)	(56,832)
Options forfeited (in shares)		(13,333)	(32,998)
Options expired (in shares)	(74,498)
Weighted Average Grant Date Fair Value
Granted (in usd per share)	$ 53.62	$ 69.20	$ 89.76
Exercised (in usd per share)	53.41
Forfeited (in usd per share)	$ 77.93	$ 90.79	$ 90.79
Grant Date 2-20-2018
Number of Shares
Options outstanding, December 31 (in shares)	88,170
Weighted Average Grant Date Fair Value
Outstanding, December 31 (in usd per share)	$ 64.33
Weighted Average Remaining Contractual Life (Years)
Options outstanding, December 31, 2022	1 month 20 days
Grant Date 2-21-2019
Number of Shares
Options outstanding, December 31 (in shares)	306,837
Weighted Average Grant Date Fair Value
Outstanding, December 31 (in usd per share)	$ 79.96
Weighted Average Remaining Contractual Life (Years)
Options outstanding, December 31, 2022	1 year 1 month 20 days
Grant Date 2-21-2020
Number of Shares
Options outstanding, December 31 (in shares)	523,500
Weighted Average Grant Date Fair Value
Outstanding, December 31 (in usd per share)	$ 90.79
Weighted Average Remaining Contractual Life (Years)
Options outstanding, December 31, 2022	2 years 1 month 24 days
Grant Date 5-1-2020
Number of Shares
Options outstanding, December 31 (in shares)	7,500
Weighted Average Grant Date Fair Value
Outstanding, December 31 (in usd per share)	$ 53.76
Weighted Average Remaining Contractual Life (Years)
Options outstanding, December 31, 2022	2 years 3 months 29 days
Grant date 2-25-2021
Number of Shares
Options outstanding, December 31 (in shares)	639,000
Weighted Average Grant Date Fair Value
Outstanding, December 31 (in usd per share)	$ 69.20
Weighted Average Remaining Contractual Life (Years)
Options outstanding, December 31, 2022	3 years 1 month 28 days
Grant date 2-25-2022
Number of Shares
Options outstanding, December 31 (in shares)	626,168
Weighted Average Grant Date Fair Value
Outstanding, December 31 (in usd per share)	$ 53.41
Weighted Average Remaining Contractual Life (Years)
Options outstanding, December 31, 2022	4 years 1 month 28 days
Grant date 6-1-2022
Number of Shares
Options outstanding, December 31 (in shares)	25,000
Weighted Average Grant Date Fair Value
Outstanding, December 31 (in usd per share)	$ 59.43
Weighted Average Remaining Contractual Life (Years)
Options outstanding, December 31, 2022	4 years 5 months 1 day