Earnings Per Share (Reconciliation of Net Earnings to Net Earnings Per Share Basic and Diluted) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share
Net earnings	$ 23,663	$ 28,302	$ 93,477	$ 95,470
Basic shares outstanding	68,323	68,922	68,506	68,973
Dilutive effect of stock options	1,107	1,397	1,192	1,473
Diluted shares outstanding	69,430	70,319	69,698	70,446
Basic earnings per share	$ 0.35	$ 0.41	$ 1.36	$ 1.38
Diluted earnings per share	$ 0.34	$ 0.40	$ 1.34	$ 1.36