LOANS & ALLOWANCE FOR CREDIT LOSSES - SCHEDULE OF UNPAID PRINCIPAL BALANCE FOR PERFORMING AND NONACCRUAL (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 26,096,037	$ 21,551,697
Nonaccrual loans to total loans	0.60%	0.79%
Single Family - Mortgage & Warehouse
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 4,581,772	$ 4,395,278
Multifamily and Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total	2,484,290	2,940,739
Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total	8,867,851	6,937,187
Commercial & Industrial - Non-RE
Financing Receivable, Credit Quality Indicator [Line Items]
Total	9,495,647	6,795,497
Auto & Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total	666,477	482,996
Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total	25,938,907	21,381,311
Performing \| Single Family - Mortgage & Warehouse
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,523,065	4,351,082
Performing \| Multifamily and Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total	2,479,258	2,907,702
Performing \| Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total	8,853,128	6,907,964
Performing \| Commercial & Industrial - Non-RE
Financing Receivable, Credit Quality Indicator [Line Items]
Total	9,418,504	6,733,693
Performing \| Auto & Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total	664,952	480,870
Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total	157,130	170,386
Nonaccrual \| Single Family - Mortgage & Warehouse
Financing Receivable, Credit Quality Indicator [Line Items]
Total	58,707	44,196
Nonaccrual \| Multifamily and Commercial Mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total	5,032	33,037
Nonaccrual \| Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total	14,723	29,223
Nonaccrual \| Commercial & Industrial - Non-RE
Financing Receivable, Credit Quality Indicator [Line Items]
Total	77,143	61,804
Nonaccrual \| Auto & Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 1,525	$ 2,126