v3.26.1
Loans Receivable And Allowance For Credit Losses (Classified Loans) (Details) - USD ($)
$ in Thousands
Mar. 31, 2026
Sep. 30, 2025
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One $ 640,990 $ 1,033,723
Year Two 954,820 560,108
Year Three 489,733 1,067,458
Year Four 877,469 1,215,877
Year Five 1,165,848 1,385,026
Prior Years 3,876,625 2,748,460
Revolving Line of Credit 127,716 117,327
Revolving Line of Credit Converted to Term Loan 7,603 8,021
Total Amortized Cost 8,140,804 8,136,000
One- to Four-Family Segment [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 118,393 233,573
Year Two 227,503 233,389
Year Three 211,670 601,344
Year Four 565,970 972,071
Year Five 933,385 1,266,835
Prior Years 3,659,951 2,607,234
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 5,716,872 5,914,446
One- to Four-Family Segment [Member] | Originated [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total Amortized Cost 3,679,335 3,776,443
One- to Four-Family Segment [Member] | Originated [Member] | Pass [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 118,393 233,573
Year Two 227,023 232,879
Year Three 210,407 296,339
Year Four 278,931 529,728
Year Five 508,747 739,138
Prior Years 2,312,503 1,722,587
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 3,656,004 3,754,244
One- to Four-Family Segment [Member] | Originated [Member] | Special Mention [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 480 0
Year Three 763 1,409
Year Four 1,501 1,099
Year Five 1,213 1,672
Prior Years 4,555 4,614
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 8,512 8,794
One- to Four-Family Segment [Member] | Originated [Member] | Substandard [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 0
Year Three 0 363
Year Four 361 568
Year Five 299 469
Prior Years 14,159 12,005
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 14,819 13,405
One- to Four-Family Segment [Member] | Correspondent Purchased [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total Amortized Cost 1,927,514 2,023,397
One- to Four-Family Segment [Member] | Correspondent Purchased [Member] | Pass [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 510
Year Three 500 301,792
Year Four 282,798 439,538
Year Five 422,286 524,927
Prior Years 1,212,420 748,902
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 1,918,004 2,015,669
One- to Four-Family Segment [Member] | Correspondent Purchased [Member] | Special Mention [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 0
Year Three 0 1,441
Year Four 1,668 523
Year Five 0 366
Prior Years 722 367
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 2,390 2,697
One- to Four-Family Segment [Member] | Correspondent Purchased [Member] | Substandard [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 0
Year Three 0 0
Year Four 711 615
Year Five 840 263
Prior Years 5,569 4,153
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 7,120 5,031
One- to Four-Family Segment [Member] | Bulk Purchased [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total Amortized Cost 110,023 114,606
One- to Four-Family Segment [Member] | Bulk Purchased [Member] | Pass [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 0
Year Three 0 0
Year Four 0 0
Year Five 0 0
Prior Years 106,343 110,862
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 106,343 110,862
One- to Four-Family Segment [Member] | Bulk Purchased [Member] | Special Mention [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 0
Year Three 0 0
Year Four 0 0
Year Five 0 0
Prior Years 1,596 1,564
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 1,596 1,564
One- to Four-Family Segment [Member] | Bulk Purchased [Member] | Substandard [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 0
Year Three 0 0
Year Four 0 0
Year Five 0 0
Prior Years 2,084 2,180
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 2,084 2,180
Commercial Segment [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 518,709 790,804
Year Two 719,945 319,284
Year Three 271,791 461,181
Year Four 307,332 239,182
Year Five 228,562 116,952
Prior Years 213,641 139,000
Revolving Line of Credit 49,776 41,536
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 2,309,756 2,107,939
Commercial Segment [Member] | Commercial Real Estate [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total Amortized Cost 2,077,923 1,898,183
Commercial Segment [Member] | Commercial Real Estate [Member] | Pass [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 439,207 639,555
Year Two 624,768 292,900
Year Three 248,004 396,152
Year Four 280,838 208,604
Year Five 200,794 111,266
Prior Years 205,043 134,388
Revolving Line of Credit 11,144 9,775
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 2,009,798 1,792,640
Commercial Segment [Member] | Commercial Real Estate [Member] | Special Mention [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 7,587
Year Two 6,847 0
Year Three 0 36,266
Year Four 0 16,060
Year Five 15,090 0
Prior Years 0 80
Revolving Line of Credit 415 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 22,352 59,993
Commercial Segment [Member] | Commercial Real Estate [Member] | Substandard [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 40,386 39,962
Year Two 0 142
Year Three 297 2,681
Year Four 2,631 0
Year Five 160 106
Prior Years 2,101 2,609
Revolving Line of Credit 198 50
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 45,773 45,550
Commercial Segment [Member] | Commercial and Industrial [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total Amortized Cost 231,833 209,756
Commercial Segment [Member] | Commercial and Industrial [Member] | Pass [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 38,932 103,700
Year Two 88,088 25,950
Year Three 23,359 26,082
Year Four 23,840 14,387
Year Five 12,409 5,555
Prior Years 6,497 1,923
Revolving Line of Credit 36,930 31,287
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 230,055 208,884
Commercial Segment [Member] | Commercial and Industrial [Member] | Special Mention [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 114 0
Year Two 0 0
Year Three 0 0
Year Four 0 44
Year Five 30 0
Prior Years 0 0
Revolving Line of Credit 220 355
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 364 399
Commercial Segment [Member] | Commercial and Industrial [Member] | Substandard [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 70 0
Year Two 242 292
Year Three 131 0
Year Four 23 87
Year Five 79 25
Prior Years 0 0
Revolving Line of Credit 869 69
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 1,414 473
Consumer Segment [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 3,888 9,346
Year Two 7,372 7,435
Year Three 6,272 4,933
Year Four 4,167 4,624
Year Five 3,901 1,239
Prior Years 3,033 2,226
Revolving Line of Credit 77,940 75,791
Revolving Line of Credit Converted to Term Loan 7,603 8,021
Total Amortized Cost 114,176 113,615
Consumer Segment [Member] | Home Equity [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total Amortized Cost 106,849 105,179
Consumer Segment [Member] | Home Equity [Member] | Pass [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 2,347 5,609
Year Two 4,961 5,532
Year Three 4,891 3,513
Year Four 3,196 3,755
Year Five 3,233 1,064
Prior Years 2,921 2,166
Revolving Line of Credit 77,486 75,067
Revolving Line of Credit Converted to Term Loan 7,490 7,937
Total Amortized Cost 106,525 104,643
Consumer Segment [Member] | Home Equity [Member] | Special Mention [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 0
Year Three 0 33
Year Four 13 0
Year Five 0 0
Prior Years 0 0
Revolving Line of Credit 64 251
Revolving Line of Credit Converted to Term Loan 79 42
Total Amortized Cost 156 326
Consumer Segment [Member] | Home Equity [Member] | Substandard [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 100
Year Two 98 0
Year Three 0 0
Year Four 0 0
Year Five 0 0
Prior Years 4 11
Revolving Line of Credit 32 57
Revolving Line of Credit Converted to Term Loan 34 42
Total Amortized Cost 168 210
Consumer Segment [Member] | Other [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Total Amortized Cost 7,327 8,436
Consumer Segment [Member] | Other [Member] | Pass [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 1,538 3,629
Year Two 2,311 1,877
Year Three 1,359 1,354
Year Four 958 824
Year Five 641 175
Prior Years 107 49
Revolving Line of Credit 358 416
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 7,272 8,324
Consumer Segment [Member] | Other [Member] | Special Mention [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 0 0
Year Two 0 0
Year Three 10 0
Year Four 0 0
Year Five 0 0
Prior Years 0 0
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost 10 0
Consumer Segment [Member] | Other [Member] | Substandard [Member]    
Financing Receivable, Credit Quality Indicator [Line Items]    
Year One 3 8
Year Two 2 26
Year Three 12 33
Year Four 0 45
Year Five 27 0
Prior Years 1 0
Revolving Line of Credit 0 0
Revolving Line of Credit Converted to Term Loan 0 0
Total Amortized Cost $ 45 $ 112