Share-Based Payments - Employee Stock Purchase Plan (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Stock Issued During Period, Shares, Employee Stock Purchase Plans	26,000	26,000
Employee Stock [Member]
Stock Issued During Period, Shares, Employee Stock Purchase Plans		25,575
Proceeds from Stock Plans		$ 747,000
Measurement Input, Price Volatility [Member] \| Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate		28.00%
Measurement Input, Expected Dividend Rate [Member] \| Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate		2.60%
Measurement Input, Risk Free Interest Rate [Member] \| Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate		2.40%
Measurement Input, Expected Term [Member] \| Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term		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 risk-free interest rate assumption that is used in valuing an option on its own shares.

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Weighted average expected volatility rate of share-based compensation awards.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

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