Note 21: Stock Compensation Plans: Schedule of Fair Value Option Pricing Model Assumptions (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Details
Expected dividends per share	$ 1,270	$ 950	$ 880
Risk-free interest rate	2.86%	2.03%	1.27%
Expected life of options	5 years	5 years	5 years
Expected volatility	17.61%	23.49%	22.08%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 8.30	$ 10.04	$ 6.59

The estimated amount of dividends to be paid to holders of the underlying shares (expected dividends) over the option's term. Dividends are taken into account because payment of dividends to shareholders reduces the fair value of the underlying shares, and option holders generally do not receive dividends.

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-Section 50
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-Subparagraph (f)(2)(iii)
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- Definition

Discloses use of the simplified method to calculate the expected term that stock option awards under the specified plan will exist before being exercised or terminated, the reason and justification for its use, and the periods for which the method was used if it was not used in all periods presented.

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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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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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No definition available.

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