DISCONTINUED OPERATIONS - Income Statement Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations	$ (7,646)	$ 88,329	$ (7,646)	$ 96,487
PPC [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue		45,832		166,262
Cost of goods and services		36,157		132,100
Gross profit		9,675		34,162
Selling, general and administrative expenses		13,995		26,103
Income from discontinued operations		(4,320)		8,059
Gain on sale of business		117,625		117,625
Interest expense, net		(95)		(155)
Other, net		166		(687)
Total other income (expense)		117,696		116,783
Income (loss) from discontinued operations		$ 113,376		$ 124,842

Disposal Group, Including Discontinued Operation, Interest Income (Expense)

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Disposal Group, Including Discontinued Operation, Selling, General and Administrative Expense

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Amount of costs of goods sold attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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