Consolidated Balance Sheet Parentheticals (USD $) In Millions, except Share data, unless otherwise specified	Sep. 30, 2011	Sep. 30, 2010
Assets
Cash, securities - fair value	$ 22.7	$ 0.8
Dep and rec -exch clear org - fair value	1,408.2	906.4
Dep and rec -b/d - fair value	16.2	56.1
Accounts pay and other accrued - fair value	$ 22.3	$ 32.3
Preferred stock - par value	$ 0.01	$ 0.01
Preferred stock - authorized	1,000,000	1,000,000
Preferred stock - issued	0	0
Preferred stock - outstanding	0	0
Common stock - par value	$ 0.01	$ 0.01
Common stock - authorized	30,000,000	30,000,000
Common stock - issued	18,653,964	17,612,792
Common stock - outstanding	18,642,407	17,601,535
Treasury stock - shares	11,557	11,257