Commitments and Contingencies - Summary of Pre-Close Environmental Costs (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Feb. 28, 2014
Commitments And Contingencies Disclosure [Abstract]
Pre-Close Environmental Costs	$ 20.0
Amount spent through February 28, 2014	(15.9)
Amount included as a component of reserves for environmental remediation costs in the unaudited condensed consolidated balance sheet as of February 28, 2014	(3.3)
Remaining Pre-Close Environmental Costs	$ 0.8

Environmental Remediation Costs Included In Environmental Reserve

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration