CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2016	Sep. 30, 2015
Equity:
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	350,000,000	350,000,000
Common stock, shares issued (in shares)	150,853,426	149,283,682
Treasury stock, shares (in shares)	9,751,304	6,364,706