Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Statement of Stockholders' Equity [Abstract]
Cash dividends on common stock per share (in dollars per share)	$ 0.99	$ 0.95	$ 0.91
Cash dividends on preferred stock per share (in dollars per share)	$ 48.75	$ 48.75	$ 33.45