Share-Based Payments - ESPP (Details) - USD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Proceeds from common shares issued pursuant to ESPP	$ 1,102,000	$ 1,458,000	$ 1,594,000
ESPP
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares authorized	2,100,000
Option to purchase	$ 25,000
Percentage of discount	15.00%
Common shares available for issuance	1,700,000
Common shares issued pursuant to employee share purchase plan (in shares)	84,673	79,040	64,321
Proceeds from common shares issued pursuant to ESPP	$ 1,100,000	$ 1,500,000	$ 1,600,000
Risk-free interest rate			0.10%
Award term	6 months	6 months	6 months
Minimum \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award
Expected volatility	30.00%	23.00%	22.00%
Dividend yield	2.40%	1.60%	1.50%
Risk-free interest rate	4.70%	0.20%
Maximum \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award
Expected volatility	37.00%	30.00%	39.00%
Dividend yield	6.30%	4.10%	3.10%
Risk-free interest rate	5.40%	2.40%

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Value of Share Per Employee

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- Definition

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

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Discount rate from fair value on purchase date that participants pay for shares.

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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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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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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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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