Interest (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Interest [Abstract]
Interest expense									$ (3,975)	$ (4,603)	$ (5,763)
Interest income									565	836	1,880
Interest income (expense), net	$ (822)	$ (788)	$ (830)	$ (970)	$ (984)	$ (866)	$ (1,014)	$ (903)	$ (3,410)	$ (3,767)	$ (3,883)