Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Earnings Per Share
Net income	$ 17,813	$ 17,563
Income allocated to participating securities	(50)	(60)
Net income available to common stockholders	$ 17,763	$ 17,503
Total basic average common shares outstanding	142,881,977	147,882,707
Total diluted average common shares outstanding	142,883,041	147,882,809
Net earnings per share:
Basic	$ 0.12	$ 0.12
Diluted	$ 0.12	$ 0.12
Antidilutive stock options, excluded from the diluted average common shares outstanding calculation	2,403,917	2,471,473
Average Common Shares Outstanding [Member]
Earnings Per Share
Total basic average common shares outstanding	142,881,528	147,881,207
Average Committed ESOP Shares Outstanding [Member]
Earnings Per Share
Total basic average common shares outstanding	449	1,500
Effect Of Dilutive Stock Options [Member]
Earnings Per Share
Total diluted average common shares outstanding	1,064	102