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INCOME TAXES (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016
INCOME TAXES (Details) [Line Items] |  |  |
U.S. Federal income tax provision (benefit) rate | 24.50% | 35.00% | 35.00%
Provisional income tax (expense) benefit | $ 20,587 |  |
Share-based compensation, excess tax benefit, amount | 2,193 |  |
Income Tax Benefits Reflected Reversal Of Previously Recorded Tax Liabilities | (421) | $ (122) | $ (2,172)
Valuation allowance increase (decrease) | 8,946 |  |
Undistributed Earnings of Foreign Subsidiaries | 64,204 |  |
Potential Tax Benefits Impact On Effective Tax Rate | 1,248 |  |
Liability for Uncertainty in Income Taxes, Current | 122 | 174 |
Deferred Tax Assets, Valuation Allowance | 7,597 | 1,343 |
Domestic Tax Authority [Member] |  |  |
INCOME TAXES (Details) [Line Items] |  |  |
Operating Loss Carryforwards | 6,089 | 1,264 |
Non U S Tax Purposes [Member] |  |  |
INCOME TAXES (Details) [Line Items] |  |  |
Operating Loss Carryforwards | 7,319 | 7,941 |
State and Local Jurisdiction [Member] |  |  |
INCOME TAXES (Details) [Line Items] |  |  |
Operating Loss Carryforwards | 124,442 | 114,837 |
Foreign Tax Authority [Member] |  |  |
INCOME TAXES (Details) [Line Items] |  |  |
Operating Loss Carryforwards | 5,740 | 1,762 |
New Accounting Pronouncement, Early Adoption, Effect [Member] |  |  |
INCOME TAXES (Details) [Line Items] |  |  |
Share-based compensation, excess tax benefit, amount | $ 1,299 | $ 4,440 |

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