Share-Based Compensation: (Details 2) (Options, USD $)	12 Months Ended
Sep. 30, 2014
1998 Plan
Information about stock options, by exercise price range
Options outstanding at the end of the period (in shares)	62,000
Options Outstanding - Weighted-Average Remaining Contractual Life	2 years 2 months 15 days
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 9.910
Options exercisable at the end of the period (in shares)	62,000
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 9.910
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
Options outstanding at the end of the period (in shares)	0
Options Outstanding - Weighted-Average Remaining Contractual Life	0 years
Options exercisable at the end of the period (in shares)	0
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)	30,000
Options Outstanding - Weighted-Average Remaining Contractual Life	3 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)	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)	28,500
Options Outstanding - Weighted-Average Remaining Contractual Life	1 year 1 month 29 days
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 12.523
Options exercisable at the end of the period (in shares)	28,500
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 12.523
1998 Plan \| Range of Exercise Price - $15.01 - $20.00
Information about stock options, by exercise price range
Exercise price, low end of range (in dollars per share)	$ 15.01
Exercise price, high end of range (in dollars per share)	$ 20.00
Options outstanding at the end of the period (in shares)	1,500
Options Outstanding - Weighted-Average Remaining Contractual Life	3 months 7 days
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 18.380
Options exercisable at the end of the period (in shares)	1,500
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 18.380
1998 Plan \| Range of Exercise Price - $20.01 - $25.00
Information about stock options, by exercise price range
Exercise price, low end of range (in dollars per share)	$ 20.01
Exercise price, high end of range (in dollars per share)	$ 25.00
Options outstanding at the end of the period (in shares)	2,000
Options Outstanding - Weighted-Average Remaining Contractual Life	9 months 6 days
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 20.853
Options exercisable at the end of the period (in shares)	2,000
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 20.853
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)	625,168
Options Outstanding - Weighted-Average Remaining Contractual Life	7 years 8 months 12 days
Options Outstanding - Weighted-Average Exercise Price (in dollars per share)	$ 3.28
Options exercisable at the end of the period (in shares)	345,167
Options Exercisable - Weighted-Average Exercise Price (in dollars per share)	$ 3.22

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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