Consolidated Statements of Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended	6 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Distribution to shareholders per share	$ 0.18	$ 0.17	$ 0.35	$ 0.34
Preferred stock, dividends per share	$ 0.3828125	$ 0.3828125	$ 0.765625	$ 0.765625
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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