Segment Reporting - Information about Operations in Different Segments (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting [Abstract]
Accrued capital expenditures		$ 38.1
Cash payments for accrued capital expenditures outstanding	$ 18.6

The amount of total capital as defined in the regulations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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