Statement of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Statement of Income and Comprehensive Income [Abstract]
Net income	$ 16,751	$ 13,196
Other Comprehensive Income
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	(18)	(625)
Total Comprehensive Income	$ 16,733	$ 12,571