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GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Summary (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Sep. 30, 2016 | Mar. 19, 2015
Financial Information |  |
Percentage ownership of subsidiary | 100.00% |
Unsecured senior notes issued March 19, 2015 |  |
Financial Information |  |
Debt issued | $ 500.0 | $ 500.0
Issuer Subsidiary | Unsecured senior notes issued March 19, 2015 |  |
Financial Information |  |
Debt issued | $ 500.0 |

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