Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Net earnings	$ 61,535	$ 58,492	$ 116,444	$ 116,487
Total weighted average basic shares	157,504,000	162,535,000	156,797,000	163,075,000
Dilutive securities:
Stock options and stock award programs (in shares)	2,116,000	3,605,000	2,048,000	3,562,000
Total weighted average diluted shares	159,620,000	166,140,000	158,845,000	166,637,000
Earnings per share:
Basic	$ 0.39us-gaap_EarningsPerShareBasic	$ 0.36us-gaap_EarningsPerShareBasic	$ 0.74us-gaap_EarningsPerShareBasic	$ 0.71us-gaap_EarningsPerShareBasic
Diluted	$ 0.39us-gaap_EarningsPerShareDiluted	$ 0.35us-gaap_EarningsPerShareDiluted	$ 0.73us-gaap_EarningsPerShareDiluted	$ 0.70us-gaap_EarningsPerShareDiluted
Common stock potentially outstanding but not included in the computation of diluted earnings per share
Options to purchase shares not included in the computation of diluted earnings per share since the options were anti-dilutive (in shares)	33,592	1,460,803	1,096,594	1,460,803

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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