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Commitments and Contingencies (Details) CAD in Millions, $ in Millions	3 Months Ended		9 Months Ended			12 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2016 CAD	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)
Loss Contingency, Damages Sought, Value | CAD				CAD 10.0
Operating Leases
Proceeds from Sale of Productive Assets			$ 0.2		$ 4.9
Loss on Walter receivable	$ 0.0	$ 11.6	0.0		$ 11.6	$ 11.6
Prior To 1995 [member]
Walter Energy tax assessment						$ 33.0
IRS-Walter Energy Claim 1 [Member]
Loss Contingency, Range of Possible Loss, Maximum	554.3		554.3
IRS-Walter Energy Claim 1 Priority [Member]
Loss Contingency, Range of Possible Loss, Maximum	229.1		229.1
IRS-Walter Energy Claim 2 [Member]
Loss Contingency, Range of Possible Loss, Maximum	860.4		860.4
IRS-Walter Energy Claim 2 Priority [Member]
Loss Contingency, Range of Possible Loss, Maximum	$ 535.3		$ 535.3

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Total amount of tax claimed for issues at a former affiliate.

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Amount of direct write-downs of accounts receivable charged against the allowance.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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