Activity Related to all Facilities and Personnel Recorded in Accrued Business Combination Costs (Detail) (USD $) In Thousands	9 Months Ended
	Jun. 30, 2011
Business Acquisition [Line Items]
Balance at September 30, 2010	$ 24,030
Charged to restructuring and other charges, net	(229)
Charged to interest expense	662
Cash payments, net of sublease receipts	(8,675)
Balance at June 30, 2011	15,788
Facilities
Business Acquisition [Line Items]
Balance at September 30, 2010	23,871
Charged to restructuring and other charges, net	(129)
Charged to interest expense	662
Cash payments, net of sublease receipts	(8,616)
Balance at June 30, 2011	15,788
Personnel
Business Acquisition [Line Items]
Balance at September 30, 2010	159
Charged to restructuring and other charges, net	(100)
Cash payments, net of sublease receipts	$ (59)