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Represents the number of reclamation obligations related to discontinued operations for which the entity remains contingently liable.

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Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Discontinued Operations (Details) $ in Thousands	3 Months Ended		9 Months Ended
Discontinued Operations (Details) $ in Thousands	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) item	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2013 USD ($)
Discontinued operations
Gain (loss) from operations of discontinued operations before income taxes	$ 440	$ (132)	$ 2,781	$ (168)
Gain (loss) on disposal	(32)	22	(3,072)	(219)
Income tax benefit (provision)	(150)	0	105	0
Income (loss) from discontinued operations, net of income taxes	258	$ (110)	$ (186)	$ (387)
Coal Cleaning Business \| Discontinued Operations, Disposed of by Sale
Discontinued operations
Remaining assets held for sale						$ 0
Number of sales transactions in which the buyer agreed to assume the lease and certain reclamation obligations \| item			1
Number of reclamation obligations \| item			1
Accrued liability for reclamation obligations	$ 9,600		$ 9,600		$ 7,400