BASIS OF PRESENTATION - Reserves For Doubtful Collection of Long-term Receivables (Details) - Allowance for Notes Receivable - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2017	Jun. 30, 2017
Allowance for Notes, Loans and Financing Receivable, Noncurrent [Roll Forward]
Balance, beginning of period	$ 17,321	$ 16,385
Additions: Charges to bad debt expense	470	1,406
Balance, end of period	17,791	17,791
Affiliates
Allowance for Notes, Loans and Financing Receivable, Noncurrent [Roll Forward]
Balance, beginning of period	17,321	16,385
Additions: Charges to bad debt expense	470	1,406
Balance, end of period	17,791	17,791
Others
Allowance for Notes, Loans and Financing Receivable, Noncurrent [Roll Forward]
Balance, beginning of period	0	0
Additions: Charges to bad debt expense	0	0
Balance, end of period	$ 0	$ 0

Allowance for Notes, Loans and Financing Receivable, Noncurrent [Roll Forward]

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- Definition

A valuation allowance relating to a written agreement to receive money (at a specified future date(s) more than one year from the reporting date, consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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- Definition

Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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