Restructuring Costs (Details 2) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Mar. 31, 2012	Sep. 30, 2011
Activity in the restructuring cost liability accrual
Balance at the beginning of the year	$ 4,438	$ 0
Costs incurred	1,357	7,370
Costs paid	(3,444)	(2,932)
Balance at the end of the year	$ 2,351	$ 4,438