Stock Compensation Plans: Disclosure of Share-based Compensation Arrangements by Share-based Payment Award (Details) - $ / shares	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Shares:
Options outstanding, beginning of period (shares)	378,304	380,820
Exercised (shares)	(16,975)	(7,400)
Granted (shares)	1,000	0
Forfeited (shares)	(450)	(3,700)
Options outstanding, end of period (shares)	361,879	369,720
Weighted Average Exercise Price (in dollars per share):
Options outstanding, beginning of period (dollars per share)	$ 18.15	$ 16.03
Exercised (dollars per share)	10.03	9.55
Granted (dollars per share)	26.50	0.00
Forfeited (dollars per share)	15.99	18.03
Options outstanding, end of period (dollars per share)	$ 18.56	$ 16.14

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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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