Loans Receivable And Allowance For Credit Losses (Allowance For Credit Losses) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				$ 31,527
Beginning Balance	$ 15,312	$ 23,397	$ 19,823
Charge-offs	(10)	(19)	(30)	(689)
Recoveries	185	71	250	207
Provision for credit losses	796	(2,725)	(3,760)	(5,560)
Ending Balance	16,283	20,724	16,283	20,724
Adoption of CECL [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				(4,761)
Balance at October 1, 2020 [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				26,766
One- to Four-Family Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				9,243
Beginning Balance	4,079	3,988	3,978
Charge-offs	0	(18)	(4)	(163)
Recoveries	126	49	137	140
Provision for credit losses	360	(71)	454	(889)
Ending Balance	4,565	3,948	4,565	3,948
One- to Four-Family Segment [Member] | Adoption of CECL [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				(4,383)
One- to Four-Family Segment [Member] | Balance at October 1, 2020 [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				4,860
One- to Four-Family Segment [Member] | Originated [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				6,085
Beginning Balance	1,709	1,536	1,612
Charge-offs	0	(18)	(4)	(142)
Recoveries	126	49	137	140
Provision for credit losses	69	(32)	159	(96)
Ending Balance	1,904	1,535	1,904	1,535
One- to Four-Family Segment [Member] | Originated [Member] | Adoption of CECL [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				(4,452)
One- to Four-Family Segment [Member] | Originated [Member] | Balance at October 1, 2020 [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				1,633
One- to Four-Family Segment [Member] | Correspondent Purchased [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				2,691
Beginning Balance	2,129	1,705	2,062
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for credit losses	308	34	375	(585)
Ending Balance	2,437	1,739	2,437	1,739
One- to Four-Family Segment [Member] | Correspondent Purchased [Member] | Adoption of CECL [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				(367)
One- to Four-Family Segment [Member] | Correspondent Purchased [Member] | Balance at October 1, 2020 [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				2,324
One- to Four-Family Segment [Member] | Bulk Purchased [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				467
Beginning Balance	241	747	304
Charge-offs	0	0	0	(21)
Recoveries	0	0	0	0
Provision for credit losses	(17)	(73)	(80)	(208)
Ending Balance	224	674	224	674
One- to Four-Family Segment [Member] | Bulk Purchased [Member] | Adoption of CECL [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				436
One- to Four-Family Segment [Member] | Bulk Purchased [Member] | Balance at October 1, 2020 [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				903
Commercial Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				21,800
Beginning Balance	11,031	19,157	15,652
Charge-offs	0	0	(10)	(515)
Recoveries	52	18	101	38
Provision for credit losses	407	(2,642)	(4,253)	(4,597)
Ending Balance	11,490	16,533	11,490	16,533
Commercial Segment [Member] | Adoption of CECL [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				(193)
Commercial Segment [Member] | Balance at October 1, 2020 [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				21,607
Consumer Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				484
Beginning Balance	202	252	193
Charge-offs	(10)	(1)	(16)	(11)
Recoveries	7	4	12	29
Provision for credit losses	29	(12)	39	(74)
Ending Balance	$ 228	$ 243	$ 228	243
Consumer Segment [Member] | Adoption of CECL [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				(185)
Consumer Segment [Member] | Balance at October 1, 2020 [Member] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning Balance				$ 299