Securities (Schedule Of Amortized Cost And Estimated Fair Value Of Securities Pledged As Collateral) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Amortized Cost [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	$ 1,036,091	$ 659,925
Estimated Fair Value [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	1,046,992	674,987
FHLB Borrowings [Member] | Amortized Cost [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	487,736	0
FHLB Borrowings [Member] | Estimated Fair Value [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	488,368	0
Public Unit Deposits [Member] | Amortized Cost [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	282,464	272,016
Public Unit Deposits [Member] | Estimated Fair Value [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	284,251	274,917
Repurchase Agreements [Member] | Amortized Cost [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	239,922	353,648
Repurchase Agreements [Member] | Estimated Fair Value [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	247,306	364,593
Federal Reserve Bank [Member] | Amortized Cost [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	25,969	34,261
Federal Reserve Bank [Member] | Estimated Fair Value [Member]
Schedule of Amortized Cost and Estimated Fair Value of Securities Pledged as Collateral [Line Items]
Securities pledged as collateral	$ 27,067	$ 35,477