Activity Related to Restructuring Accruals (Detail) (USD $) In Thousands	12 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Restructuring Cost and Reserve [Line Items]
Beginning Balance	$ 3,509	$ 7,661	$ 12,663
Restructuring costs	1,036	2,529	12,806
Utilization	(4,252)	(6,681)	(17,808)
Ending Balance	293	3,509	7,661
Facilities
Restructuring Cost and Reserve [Line Items]
Beginning Balance	3,509	6,289	9,658
Restructuring costs	310	1,584	1,769
Utilization	(3,819)	(4,364)	(5,138)
Ending Balance		3,509	6,289
Workforce-related
Restructuring Cost and Reserve [Line Items]
Beginning Balance		1,372	3,005
Restructuring costs	726	945	11,037
Utilization	(433)	(2,317)	(12,670)
Ending Balance	$ 293		$ 1,372

Amount of cash paid in the period to fully or partially settle a specified, previously accrued type of restructuring cost.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b)(2))

-URI http://asc.fasb.org/extlink&oid=6394695&loc=d3e140904-122747

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 95-3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

Reference 5: 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Name:	us-gaap_RestructuringReserveSettledWithCash
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration