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COMMITMENTS AND CONTINGENT LIABILITIES - SCHEDULE OF FUTURE COMMITTED EXPENSES (Details) $ in Thousands | 12 Months Ended
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Sep. 30, 2017 USD ($)
Long-term Purchase Commitment [Line Items] |
Current charges recoverable through BGSS | $ 98,600
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 534,913
2019 | 339,742
2020 | 178,178
2021 | 141,612
2022 | 123,149
Thereafter | 668,441
Energy Services |
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 385,277
2019 | 169,867
2020 | 59,424
2021 | 42,150
2022 | 25,486
Thereafter | 22,057
Energy Services | Natural gas purchases |
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 296,491
2019 | 114,817
2020 | 22,270
2021 | 11,488
2022 | 0
Thereafter | 0
Energy Services | Storage demand fees |
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 32,870
2019 | 22,638
2020 | 13,350
2021 | 9,041
2022 | 5,833
Thereafter | 2,746
Energy Services | Pipeline demand fees |
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 55,916
2019 | 32,412
2020 | 23,804
2021 | 21,621
2022 | 19,653
Thereafter | 19,311
Natural Gas Distribution |
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 149,636
2019 | 169,875
2020 | 118,754
2021 | 99,462
2022 | 97,663
Thereafter | 646,384
Natural Gas Distribution | Natural gas purchases |
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 51,050
2019 | 41,156
2020 | 2,514
2021 | 0
2022 | 0
Thereafter | 0
Natural Gas Distribution | Storage demand fees |
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 30,042
2019 | 26,628
2020 | 15,331
2021 | 8,231
2022 | 7,804
Thereafter | 3,903
Natural Gas Distribution | Pipeline demand fees |
Purchase Obligation, Fiscal Year Maturity [Abstract] |
2018 | 68,544
2019 | 102,091
2020 | 100,909
2021 | 91,231
2022 | 89,859
Thereafter | $ 642,481
Minimum |
Long-term Purchase Commitment [Line Items] |
Storage and pipeline capacity, fixed period | 1 year
Maximum |
Long-term Purchase Commitment [Line Items] |
Storage and pipeline capacity, fixed period | 10 years

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- Definition Minimum amount of purchase arrangement maturing after the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments. + References No definition available. + Details
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