FAIR VALUE - QUANTITATIVE INFORMATION ABOUT LEVEL 3 FAIR VALUE MEASURMENTS (RECURRING) (Details) $ in Thousands	Sep. 30, 2023 USD ($) year	Jun. 30, 2023 USD ($) year
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities – Non-agency MBS	$ 236,726	$ 232,350
Securities – Available-for-Sale: Non-Agency RMBS
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities – Non-agency MBS	206,076	205,005
Level 3
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities – Non-agency MBS	206,076	205,005
Servicing rights	29,338	25,443
Recurring
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities – Non-agency MBS	236,726	232,350
Servicing rights	29,338	25,443
Recurring \| Securities – Available-for-Sale: Non-Agency RMBS
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities – Non-agency MBS	206,076	205,005
Recurring \| Level 3
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities – Non-agency MBS	206,076	205,005
Servicing rights	29,338	25,443
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities – Non-agency MBS	$ 206,076	$ 205,005
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Constant Prepayment Rate \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.000	0.000
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Constant Prepayment Rate \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.581	0.597
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Constant Prepayment Rate \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.349	0.320
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Constant Default Rate \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.000	0.000
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Constant Default Rate \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.076	0.075
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Constant Default Rate \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.024	0.024
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Loss Severity \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.000	0.000
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Loss Severity \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.687	0.687
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Projected Loss Severity \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.285	0.285
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Discount Rate \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.026	0.026
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Discount Rate \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.065	0.075
Recurring \| Level 3 \| Securities – Available-for-Sale: Non-Agency RMBS \| Discount Rate \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Securities available-for-sale, measurement input	0.026	0.027
Recurring \| Level 3 \| Servicing Rights
Fair Value, Option, Quantitative Disclosures [Line Items]
Servicing rights	$ 29,338	$ 25,443
Recurring \| Level 3 \| Servicing Rights \| Projected Constant Prepayment Rate \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input	0.048	0.061
Recurring \| Level 3 \| Servicing Rights \| Projected Constant Prepayment Rate \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input	0.399	0.401
Recurring \| Level 3 \| Servicing Rights \| Projected Constant Prepayment Rate \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input	0.130	0.126
Recurring \| Level 3 \| Servicing Rights \| Discount Rate \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input	0.095	0.095
Recurring \| Level 3 \| Servicing Rights \| Discount Rate \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input	0.115	0.115
Recurring \| Level 3 \| Servicing Rights \| Discount Rate \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input	0.098	0.096
Recurring \| Level 3 \| Servicing Rights \| Life (in years) \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input \| year	1.7	1.8
Recurring \| Level 3 \| Servicing Rights \| Life (in years) \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input \| year	15.8	10.9
Recurring \| Level 3 \| Servicing Rights \| Life (in years) \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgage servicing right, measurement input \| year	7.4	7.7

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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