Activity Related to Liability for Special Charges (Parenthetical) (Detail) $ in Millions	3 Months Ended
Dec. 31, 2015 USD ($)
Selling, General and Administrative Expenses
Special Charges [Line Items]
Expected sublease income	$ 0.4

The amount of revenue recognized for the period under subleasing arrangements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 55
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6584307&loc=d3e41620-112719

Name:	us-gaap_OperatingLeasesIncomeStatementSubleaseRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration