Securities (Schedule Of Estimated Fair Value And Gross Unrealized Losses Of Securities In Continuous Unrealized Loss Position) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013 security	Sep. 30, 2013 security
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Count	21	19
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Estimated Fair Value	$ 484,635	$ 426,482
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	9,601	7,213
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Count	3	2
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Estimated Fair Value	40,005	26,750
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Unrealized Losses	1,724	844
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Estimated Fair Value	810,794	711,590
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	27,883	16,998
Held-to-maturity Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Estimated Fair Value	22,741
Held-to-maturity Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Unrealized Losses	1,559
Less Than 12 Months [Member]
Schedule of Investments [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Count	54	43
Equal to or Greater Than 12 Months [Member]
Schedule of Investments [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Count	3
GSE Debentures [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Count	21	19
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Estimated Fair Value	484,635	426,482
Available-for-sale Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	9,601	7,213
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Count	2	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Estimated Fair Value	37,596	24,327
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Unrealized Losses	1,554	673
Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Count	1	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Estimated Fair Value	2,409	2,423
Available-for-sale Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Unrealized Losses	170	171
MBS [Member]
Schedule of Investments [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Estimated Fair Value	806,066	710,291
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	27,862	16,984
Held-to-maturity Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Estimated Fair Value	22,741
Held-to-maturity Securities, Continuous Unrealized Loss Position, Equal to or Greater Than 12 Months, Unrealized Losses	1,559
MBS [Member] | Less Than 12 Months [Member]
Schedule of Investments [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Count	46	40
MBS [Member] | Equal to or Greater Than 12 Months [Member]
Schedule of Investments [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Count	3
Municipal Bonds [Member]
Schedule of Investments [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Estimated Fair Value	4,728	1,299
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less Than 12 Months, Unrealized Losses	$ 21	$ 14
Municipal Bonds [Member] | Less Than 12 Months [Member]
Schedule of Investments [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Count	8	3