Share-Based Payments - ESPP (Details) - USD ($)	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Proceeds from common shares issued pursuant to ESPP	$ 880,000	$ 887,000
ESPP
Share-based Compensation Arrangement by Share-based Payment Award
Common shares issued pursuant to employee share purchase plan (in shares)	34,320
Proceeds from common shares issued pursuant to ESPP	$ 880,000
Expected volatility	39.00%
Dividend yield	1.50%
Risk-free interest rate	0.10%
Expected life	6 months

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

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

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

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