Stock Compensation Plans: Disclosure of Share-based Compensation Arrangements by Share-based Payment Award (Details) - $ / shares	3 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Shares:
Options outstanding, beginning of period (shares)	421,925	406,815
Exercised (shares)	(19,815)	(8,900)
Granted (shares)	0	1,000
Forfeited (shares)	(1,800)	(11,594)
Options outstanding, end of period (shares)	400,310	387,321
Weighted Average Exercise Price (in dollars per share):
Options outstanding, beginning of period (dollars per share)	$ 23.30	$ 21.62
Exercised (dollars per share)	20.01	14.63
Granted (dollars per share)	0	27.25
Forfeited (dollars per share)	29.68	25.28
Options outstanding, end of period (dollars per share)	$ 23.43	$ 21.70

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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