Commitments and Contingencies: (Details) (USD $)	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Capital Lease
Term of lease	5 years
Implicit interest rate (as a percent)	7.20%
Capitalized cost included in property and equipment	$ 57,450
Annual amortization	5,000	5,000	7,000
Balance due on leases	0	13,000	26,000
Operating Leases
Rent expense under operating leases	30,000	31,000	26,000
Product Liability
Product liability insurance	$ 50,000,000
Net sales \| Major Customers
Legal Proceedings
Concentration of risk (as a percent)	63.00%	61.00%	48.00%
Net sales \| Major Customers \| American Airlines, Inc. ("AAI")
Legal Proceedings
Concentration of risk (as a percent)	5.00%	8.00%	8.00%

Represents the percentage of implicit interest rate on leased assets under the capital lease.

No definition available.

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- Definition

Represents the term of capital lease.

+ References

No definition available.

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- Definition

Represents amount of insurance which is adequate to cover potential liabilities that may arise from product liability claims.

+ References

No definition available.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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- Definition

The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)

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- Definition

The charge for the use of long-lived depreciable capital leased assets for the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45031-112735

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Topic 980

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

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-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

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