Employee Benefit Plans - Fair Value Assumptions (Details) - $ / shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Options granted (in shares)	89,000	101,000
Weighted Average Exercise Price: Options granted (in usd per share)	$ 19.21	$ 20.39
Weighted average fair value of options (in usd per share)	$ 7.72	$ 5.54
Expected life in years	8 years 4 months 17 days	8 years 7 months 28 days
Expected volatility	43.69%	27.13%
Risk-free interest rate	1.14%	1.55%
Dividend yield	1.68%	1.61%
Restricted Stock \| 2019 Equity Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award
Options granted (in shares)	281,500

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 estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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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

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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- Definition

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

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No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

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

+ References

No definition available.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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