Share-Based Payments - ESPP (Details) - USD ($)	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognition period (in years)	1 year 10 months 24 days
Proceeds from common stock issued pursuant to ESPP	$ 887,000	$ 747,000
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares issued pursuant to Employee Share Purchase Plan ( in shares)	35,307
Proceeds from common stock issued pursuant to ESPP	$ 887,000
Expected volatility	13.00%
Dividend yield	1.10%
Risk-free interest rate	1.70%
Expected life	6 months

Weighted-average period over which cost not yet recognized is expected to be recognized for 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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- Definition

The cash inflow associated with the amount received from the stock plan during the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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 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.

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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

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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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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