Share-Based Compensation: (Details 2) - Options	12 Months Ended
	Sep. 30, 2015 $ / shares shares
1998 Plan
Information about stock options, by exercise price range
Options outstanding at the end of the period (in shares) | shares	53,000
Options Outstanding - Weighted-Average Remaining Contractual Life	1 year 6 months
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 8.830
Options exercisable at the end of the period (in shares) | shares	53,000
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 8.830
1998 Plan | Range of Exercise Price - $0.00 - $5.00
Information about stock options, by exercise price range
Exercise price, low end of range (in dollars per share)	0.00
Exercise price, high end of range (in dollars per share)	5.00
1998 Plan | Range of Exercise Price - $5.01 - $10.00
Information about stock options, by exercise price range
Exercise price, low end of range (in dollars per share)	5.01
Exercise price, high end of range (in dollars per share)	$ 10.00
Options outstanding at the end of the period (in shares) | shares	30,000
Options Outstanding - Weighted-Average Remaining Contractual Life	2 years 4 months 23 days
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 6.270
Options exercisable at the end of the period (in shares) | shares	30,000
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 6.270
1998 Plan | Range of Exercise Price - $10.01 - $15.00
Information about stock options, by exercise price range
Exercise price, low end of range (in dollars per share)	10.01
Exercise price, high end of range (in dollars per share)	$ 15.00
Options outstanding at the end of the period (in shares) | shares	23,000
Options Outstanding - Weighted-Average Remaining Contractual Life	4 months
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 12.166
Options exercisable at the end of the period (in shares) | shares	23,000
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 12.166
2009 Plan | Range of Exercise Price - $0.00 - $5.00
Information about stock options, by exercise price range
Exercise price, low end of range (in dollars per share)	0.00
Exercise price, high end of range (in dollars per share)	$ 5.00
Options outstanding at the end of the period (in shares) | shares	592,168
Options Outstanding - Weighted-Average Remaining Contractual Life	6 years 8 months 12 days
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 3.35
Options exercisable at the end of the period (in shares) | shares	508,834
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 3.23