Fair Value Of Financial Instruments (Schedule Of Carrying Amounts And Estimated Fair Values Of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Sep. 30, 2013
Assets:
Available-for-sale ("AFS")	$ 857,372	$ 1,069,967
HTM securities	1,663,917	1,741,846
OREO	3,278	3,882
Carrying Amount [Member]
Assets:
Cash and cash equivalents	88,424	113,886
Available-for-sale ("AFS")	857,372	1,069,967
HTM securities	1,637,043	1,718,023
Loans receivable	6,132,520	5,958,868
BOLI	60,496	59,495
FHLB stock	112,876	128,530
OREO	3,278	3,882
Liabilities:
Deposits	4,654,862	4,611,446
FHLB borrowings	2,468,420	2,513,538
Repurchase agreements	320,000	320,000
Estimated Fair Value [Member]
Assets:
Cash and cash equivalents	88,424	113,886
Available-for-sale ("AFS")	857,372	1,069,967
HTM securities	1,663,917	1,741,846
Loans receivable	6,352,851	6,132,239
BOLI	60,496	59,495
FHLB stock	112,876	128,530
OREO	3,278	3,882
Liabilities:
Deposits	4,680,230	4,646,263
FHLB borrowings	2,537,909	2,599,749
Repurchase agreements	$ 329,941	$ 333,749