Authorized shares of common and preferred stock and stock-based compensation plans (Details) - Performance Shares - simulation simulation in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of simulations	100	100
Expected volatility	37.81%	40.60%
Expected life in years	2 years 11 months 12 days	2 years 11 months 12 days
Risk-free interest rate	1.33%	0.21%
Dividend yield	2.52%	2.66%

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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

Rate of weighted-average expected volatility for award under share-based payment arrangement.

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- Definition

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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- 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.

+ References

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