Nature of Operations and Summary of Significant Accounting Policies - Revenues and Long-Term Assets Information Concerning Principal Geographic Areas (Detail) (USD $)	3 Months Ended								12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]
Net revenues	$ 4,910,000	$ 10,547,000	$ 14,541,000	$ 10,019,000	$ 7,568,000	$ 18,690,000	$ 17,737,000	$ 4,948,000	$ 40,017,000	$ 48,943,000
Long-Term Assets	7,209,000				8,157,000				7,209,000	8,157,000
United States [Member]
Segment Reporting Information [Line Items]
Net revenues									40,017,000	48,943,000
Long-Term Assets	7,209,000				7,913,000				7,209,000	7,913,000
United Kingdom [Member]
Segment Reporting Information [Line Items]
Net revenues									0	0
Long-Term Assets	$ 0				$ 244,000				$ 0	$ 244,000