Fair Value Of Financial Instruments (Schedule Of Carrying Amounts And Estimated Fair Values Of Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Assets:
AFS Securities	$ 740,462	$ 1,384,482
Significant Unobservable Inputs (Level 3) [Member]
Assets:
Loans receivable	1,100		$ 4,100
Carrying Amount [Member]
Assets:
Cash and cash equivalents	320,357	245,605
AFS Securities	740,462	1,384,482
Loans receivable	7,947,510	7,970,949
FHLB stock	110,166	110,714
Interest rate swaps	6,487	13,018
Liabilities:
Deposits	6,021,595	6,051,220
Borrowings	2,373,064	2,879,125
Estimated Fair Value [Member]
Assets:
Cash and cash equivalents	320,357	245,605
AFS Securities	740,462	1,384,482
Loans receivable	7,561,055	7,358,462
FHLB stock	110,166	110,714
Interest rate swaps	6,487	13,018
Liabilities:
Deposits	6,003,615	6,004,975
Borrowings	2,331,484	2,802,849
Estimated Fair Value [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets:
Cash and cash equivalents	320,357	245,605
AFS Securities	213,758	0
Loans receivable	0	0
FHLB stock	110,166	110,714
Interest rate swaps	0	0
Liabilities:
Deposits	3,282,768	3,321,028
Borrowings	0	0
Estimated Fair Value [Member] | Significant Other Observable Inputs (Level 2) [Member]
Assets:
Cash and cash equivalents	0	0
AFS Securities	526,704	1,384,482
Loans receivable	0	0
FHLB stock	0	0
Interest rate swaps	6,487	13,018
Liabilities:
Deposits	2,720,847	2,683,947
Borrowings	2,331,484	2,802,849
Estimated Fair Value [Member] | Significant Unobservable Inputs (Level 3) [Member]
Assets:
Cash and cash equivalents	0	0
AFS Securities	0	0
Loans receivable	7,561,055	7,358,462
FHLB stock	0	0
Interest rate swaps	0	0
Liabilities:
Deposits	0	0
Borrowings	$ 0	$ 0