Restructuring-Related Charges and Accruals - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 214
Workforce-related
Restructuring Cost and Reserve [Line Items]
Restructuring charges	203	165
Facilities and other
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 49

Reserve increase representing the amount charged against earnings in the period for a specified incurred and estimated type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 146

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)(2)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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