Securities (Schedule Of Contractual Maturities) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Sep. 30, 2013
Securities [Abstract]
Available-for-sale Securities, One year or less, Amortized Cost	$ 200
Available-for-sale Securities, One year through five years, Amortized Cost	510,931
Available-for-sale Securities, Five years through ten years, Amortized Cost	131,298
Available-for-sale Securities, Ten years and thereafter, Amortized Cost	203,529
Available-for-sale Securities, Amortized Cost	845,958	1,058,283
Available-for-sale Securities, One year or less, Estimated Fair Value	202
Available-for-sale Securities, One year through five years, Estimated Fair Value	508,456
Available-for-sale Securities, Five years through ten years, Estimated Fair Value	135,501
Available-for-sale Securities, Ten years and thereafter, Estimated Fair Value	213,213
Available-for-sale Securities, Estimated Fair Value	857,372	1,069,967
Held-to-maturity Securities, One year or less, Amortized Cost	5,414
Held-to-maturity Securities, One year through five years, Amortized Cost	81,251
Held-to-maturity Securities, Five years through ten years, Amortized Cost	458,521
Held-to-maturity Securities, Ten years and thereafter, Amortized Cost	1,091,857
Held-to-maturity Securities, Amortized Cost	1,637,043	1,718,023
Held-to-maturity Securities, One year or less, Estimated Fair Value	5,451
Held-to-maturity Securities, One year through five years, Estimated Fair Value	85,476
Held-to-maturity Securities, Five years through ten years, Estimated Fair Value	461,267
Held-to-maturity Securities, Ten years and thereafter, Estimated Fair Value	1,111,723
Held-to-maturity Securities, Estimated Fair Value	$ 1,663,917	$ 1,741,846