Stock-based Employee Compensation, Stock Option Plans, and Deferred Compensation Plan for Directors - Stock Options Issued (Details)			9 Months Ended
May 07, 2021 $ / shares	Apr. 24, 2020 $ / shares	Sep. 30, 2021 $ / shares
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Exercise price (in usd per share)			$ 41.82
Directors
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Exercise price (in usd per share)	$ 43.89	$ 50.00
Volatility	0.297	0.258
Expected life (years)	5 years	5 years
Assumed yield	4.96%	3.80%
Risk-free rate	0.77%	0.36%
Officers
Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]
Exercise price (in usd per share)	$ 43.89	$ 50.00
Volatility	0.275	0.240
Expected life (years)	7 years	7 years
Assumed yield	4.97%	3.85%
Risk-free rate	1.24%	0.51%

Share Based Compensation Arrangement by Share Based Payment Award, Fair Value Assumptions, Volatility

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- Definition

Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items]

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

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

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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