Parent Company Only Financial Statements (Schedule Of Statements Of Condition) (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Assets
Cash and due from banks	$ 24,176	$ 26,287
Investment securities available-for-sale	520,659	526,251
Investments in
Other assets	111,687	114,125
TOTAL ASSETS	17,456,316	17,090,785
Liabilities and shareholders' equity
Accrued expenses and other liabilities	101,709	97,845
Total liabilities	$ 15,562,392	$ 15,228,161
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares issued	0	0
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares outstanding	0	0
Preferred stock	$ 0	$ 0
Common stock, shares issued	332,318,750	332,318,750
Common stock, shares authorized	700,000,000	700,000,000
Common stock, shares outstanding	280,590,497	280,710,854
Common stock, par value	$ 0.01	$ 0.01
Common stock	$ 3,323	$ 3,323
Paid-in capital	1,757,813	1,754,365
Treasury Stock, Value	$ (774,340)	$ (772,195)
Treasury stock, at cost	51,728,253	51,607,896
Unallocated ESOP shares	$ (18,417)	$ (22,750)
Retained earnings - substantially restricted	946,776	915,489
Accumulated other comprehensive loss	(21,231)	(15,608)
Total shareholders' equity	1,893,924	1,862,624	$ 1,927,361	$ 1,844,339
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	17,456,316	17,090,785
TFS Financial Corporation
Assets
Cash and due from banks	1,679	1,556
Investment securities available-for-sale	3,923	3,844
Investments in
Prepaid federal and state taxes	92	75
Deferred income taxes	0	80
Other assets	8,662	9,277
TOTAL ASSETS	1,905,837	1,873,759
Liabilities and shareholders' equity
Accrued expenses and other liabilities	3,093	2,696
Deferred Income Tax Liabilities, Net	123	0
Total liabilities	$ 11,913	$ 11,135
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares issued	0	0
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares outstanding	0	0
Preferred stock	$ 0	$ 0
Common stock, shares issued	332,318,750	332,318,750
Common stock, shares authorized	700,000,000	700,000,000
Common stock, shares outstanding	280,590,497	280,710,854
Common stock, par value	$ 0.01	$ 0.01
Common stock	$ 3,323	$ 3,323
Paid-in capital	1,757,813	1,754,365
Treasury Stock, Value	$ (774,340)	$ (772,195)
Treasury stock, at cost	51,728,253	51,607,896
Unallocated ESOP shares	$ (18,417)	$ (22,750)
Retained earnings - substantially restricted	946,776	915,489
Accumulated other comprehensive loss	(21,231)	(15,608)
Total shareholders' equity	1,893,924	1,862,624
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	1,905,837	1,873,759
TFS Financial Corporation | Line of Credit
Liabilities and shareholders' equity
Due to non-banking affiliate	8,697	8,439
TFS Financial Corporation | Demand loan due from Third Federal Savings and Loan
Other Loans
Due from Affiliates	111,178	124,683
TFS Financial Corporation | ESOP loan receivable
Other Loans
Due from Affiliates	28,571	33,015
TFS Financial Corporation | Bank Subsidiary
Investments in
Investments in	1,743,060	1,692,789
TFS Financial Corporation | Non Bank Subsidiary
Investments in
Investments in	$ 8,672	$ 8,440