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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - SALES TAX ACCOUNTING (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2017 | Mar. 31, 2016 | Mar. 31, 2017 | Mar. 31, 2016 | Jan. 01, 2017 | Dec. 31, 2016
Subsequent Event [Line Items] |  |  |  |  |  |
Sales tax | $ 16.9 | $ 13.5 | $ 28.1 | $ 20.7 |  |
NEW JERSEY |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
State sales tax, percent |  |  |  |  | 6.875% | 7.00%

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- Definition Sales Tax + References No definition available. + Details
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- Definition State Sales Tax, Percent + References No definition available. + Details
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Balance Type: | na
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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Period Type: | duration

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |