LOANS & ALLOWANCE FOR CREDIT LOSSES - UNPAID PRINCIPAL BALANCE FOR PERFORMING AND NONACCRUAL (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Jun. 30, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 18,860,409	$ 16,652,026
Nonaccrual loans to total loans	0.65%	0.52%
Single Family - Mortgage & Warehouse
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 4,092,104	$ 4,173,833
Multifamily and Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,065,019	3,082,225
Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total	6,043,400	6,199,818
Commercial & Industrial - Non-RE
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,177,461	2,639,650
Auto & Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total	477,275	546,264
Other
Financing Receivable, Credit Quality Indicator [Line Items]
Total	5,150	10,236
Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total	18,737,901	16,564,866
Performing \| Single Family - Mortgage & Warehouse
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,037,817	4,143,119
Performing \| Multifamily and Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,027,695	3,047,122
Performing \| Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total	6,017,298	6,184,966
Performing \| Commercial & Industrial - Non-RE
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,174,472	2,636,661
Performing \| Auto & Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total	475,505	544,807
Performing \| Other
Financing Receivable, Credit Quality Indicator [Line Items]
Total	5,114	8,191
Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total	122,508	87,160
Nonaccrual \| Single Family - Mortgage & Warehouse
Financing Receivable, Credit Quality Indicator [Line Items]
Total	54,287	30,714
Nonaccrual \| Multifamily and Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total	37,324	35,103
Nonaccrual \| Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total	26,102	14,852
Nonaccrual \| Commercial & Industrial - Non-RE
Financing Receivable, Credit Quality Indicator [Line Items]
Total	2,989	2,989
Nonaccrual \| Auto & Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total	1,770	1,457
Nonaccrual \| Other
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 36	$ 2,045

Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481598/310-20-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-79

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