Restructuring and Other Charges, net (Accrual Activity Relating to Restructuring and Other Charges) (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Mar. 31, 2013
Restructuring [Roll Forward]
Balance at September 30, 2012	$ 1,740
Restructuring charges, net	7,551
Cash payments	(3,738)
Balance at March 31, 2013	5,553
Personnel
Restructuring [Roll Forward]
Balance at September 30, 2012	1,708
Restructuring charges, net	6,629
Cash payments	(3,542)
Balance at March 31, 2013	4,795
Facilities
Restructuring [Roll Forward]
Balance at September 30, 2012	32
Restructuring charges, net	922
Cash payments	(196)
Balance at March 31, 2013	$ 758