Equity Investments (Details) (USD $)	12 Months Ended		115 Months Ended	0 Months Ended	116 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Management Agreement With Windspeed Member	Feb. 21, 2011 Windspeed	Sep. 30, 2013 Windspeed
Equity Investments
Percentage of proceeds from certain companies in the portfolio that will go to Windspeed				100.00%
Proceeds from sale of equity investments prior to Windspeed's management fees and sharing			$ 71,042,000
Payment of management fees and sharing					12,779,000
Proceeds (after sharing) on the sale of marketable equity securities	112,000	328,000
Realized gain on the sale of marketable equity securities	112,000	203,000
Equity investments in private companies	697,000	697,000
Write-downs of equity securities	$ 0	$ 0