Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Distribution to shareholders per share	$ 0.71	$ 0.68	$ 0.68
Preferred Stock, Dividends Per Share	$ 1.53125	$ 1.53125	$ 1.53125
Preferred Stock Series C [Member] \| At The Market Offerings [Member]
Preferred Stock, Dividend Rate, Percentage	6.125%	6.125%	6.125%

Per share or unit amount of distribution to shareholders. Includes, but is not limited to, dividend and capital gain. Excludes distribution for tax return of capital.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 205
-Section 50
-Paragraph 7
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=25866437&loc=d3e10246-115837

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