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Commitments and Contingencies (Details) CAD in Millions, $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2017 USD ($) | Mar. 31, 2017 CAD | Dec. 31, 2014 USD ($)
Loss Contingency, Damages Sought, Value | CAD |  | CAD 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, Range of Possible Loss, Maximum | 554.3 |  |
IRS-Walter Energy Claim 1 Priority [Member] |  |  |
Loss Contingency, Range of Possible Loss, Maximum | 229.1 |  |
IRS-Walter Energy Claim 2 [Member] |  |  |
Loss Contingency, Range of Possible Loss, Maximum | 860.4 |  |
IRS-Walter Energy Claim 2 Priority [Member] |  |  |
Loss Contingency, Range of Possible Loss, Maximum | $ 535.3 |  |

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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 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 + Details
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- Definition The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph ((c)(3,4)) -URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
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