CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Statement of Stockholders' Equity [Abstract]
Cash dividends declared and paid, quarterly, per as-converted share	$ 0.165	$ 0.14	$ 0.12