Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Statement of Stockholders' Equity [Abstract]
Dividends declared (in usd per share)	$ 0.70	$ 0.66
Issuance of stock (in shares)	56,802	47,141
Options exercised (in shares)	29,992	31,508

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

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