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ASSET RETIREMENT OBLIGATIONS (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Sep. 30, 2014 | Sep. 30, 2013
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |  |
Balance at October 1 | $ 28,711 | $ 27,983
Accretion | 2,012 | 1,892
Additions | 925 | 533
Retirements | (1,153) | (1,697)
Balance at period end | 30,495 | 28,711
Future Accretion [Abstract] |  |
2015 | 2,075 |
2016 | 2,139 |
2017 | 2,194 |
2018 | 2,248 |
2019 | 2,303 |
Total | $ 10,959 |

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- Definition The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Asset Retirement Obligation -URI http://asc.fasb.org/extlink&oid=6505190 + Details
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- Definition Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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