Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Income Tax Disclosure [Abstract]
U.S. federal statutory tax rate	35.00%	35.00%		35.00%
Federal research and development credit	$ 67,000	$ 324,000	$ 200,000
Income tax expense from discontinued operations		500,000		1,100,000
Income tax benefit from discontinued operations	100,000			600,000
Net reversal of deferred tax asset valuation allowances	500,000	1,200,000
Valuation allowance				300,000
Unrecognized tax benefits including interest and penalties	900,000	1,000,000		1,000,000
Liability for unrecognized tax benefits to change significantly in the next 12 months	$ 600,000	$ 700,000		$ 800,000