CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (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
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ (37,152)	$ 18,405	$ 29,702	$ 14,314	$ 21,967	$ 27,448	$ 25,907	$ 22,309	$ 25,269	$ 97,631	$ 86,354
Other comprehensive income (loss):
Adjustment to pension liability, net of tax	13,106				(5,585)				13,106	(5,585)	(3,285)
Foreign currency translation	16,739	(1,776)	(15,338)	1,349	7,578	(5,004)	7,975	328	974	10,877	(1,329)
Net unrealized gain (loss) from cash flow hedges, net of tax	(926)	4,706	(745)	742	(598)	(1,288)	3,288	(1,160)	3,777	242	(5,618)
Net unrealized gain (loss) on available-for-sale securities, net of tax	3	(5)							(2)
Total other comprehensive income (loss)	28,922	2,925	(16,083)	2,091	1,395	(6,292)	11,263	(832)	17,855	5,534	(10,232)
Total comprehensive income	$ (8,230)	$ 21,330	$ 13,619	$ 16,405	$ 23,362	$ 21,156	$ 37,170	$ 21,477	$ 43,124	$ 103,165	$ 76,122