INCOME TAXES (Details) - USD ($)	3 Months Ended	9 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
INCOME TAXES [Abstract]
Effective income tax rate	22.40%	9.60%	21.10%	14.20%
Tax benefit for additional domestic production deductions				$ 900
Income Tax Holiday [Line Items]
Former tax holiday percentage (in hundredths)	0.00%		0.00%
Tax Holiday approximate diluted earning per share benefit (in dollars per share)			$ 0.12	$ 0.11
Foreign Country [Member] \| South Korea [Member]
Income Tax Holiday [Line Items]
Percentage of local statutory rate in effect for 2016	50.00%		50.00%
Percentage of local statutory rate in effect for 2017	50.00%		50.00%
Income tax provision reduction as a result of the tax holiday			$ 3,094,000	$ 2,717,000

Percentage applicable on federal statutory tax rate for period 4.

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Percentage applicable on federal statutory tax rate for period 3.

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The Company has been awarded a tax holiday in South Korea with respect to its manufacturing operations.

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No definition available.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319

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The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330215-122817

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Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of the difference between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

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