Regulatory Requirements - Additional Information (Detail) - Jun. 30, 2015 - USD ($)	Total
Regulatory Capital Requirements [Abstract]
Minimum net capital required	$ 5,000
Description of minimum net capital requirements	The greater of $5,000 or 1/15 of aggregate indebtedness
Minimum net capital requirements (percent)	6.67%
Net capital	$ 11,300,000
Excess net capital	$ 10,700,000
Aggregate indebtedness to net capital ratio (percent)	0.8