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Commitments and Contingencies (Details) $ in Millions, $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2017 USD ($)	Mar. 31, 2018 CAD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2014 USD ($)
Loss Contingency, Damages Sought, Value		$ 10.0
Operating Leases
Product Warranty Expense	$ 9.8
Prior To 1995 [member]
Walter Energy tax assessment				$ 33.0
IRS-Walter Energy Claim 1 [Member]
Loss Contingency, Estimate of Possible Loss			$ 554.3
IRS-Walter Energy Claim 1 Priority [Member]
Loss Contingency, Estimate of Possible Loss			229.1
IRS-Walter Energy Claim 2 [Member]
Loss Contingency, Estimate of Possible Loss			860.4
IRS-Walter Energy Claim 2 Priority [Member]
Loss Contingency, Estimate of Possible Loss			$ 535.3

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

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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