LOANS HELD FOR INVESTMENT - Corporation's Aging of Loans Held for Investment Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Financing Receivable, Past Due [Line Items]
Loans held for investment	$ 13,091,077	$ 13,125,356
Nonaccrual Loans with No ACL	19,046	16,391
Loans Past Due 90 days or more and Still Accruing	28,949	31,913
Financing Receivable, Nonaccrual	87,744	92,563
Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	12,863,864	12,855,903
30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	67,436	90,610
60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	43,084	54,367
Residential Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,914,898	2,908,302
Residential Portfolio Segment [Member] \| Conventional Residential Mortgage Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,826,559	2,819,582
Nonaccrual Loans with No ACL	0	0
Loans Past Due 90 days or more and Still Accruing	5,529	6,069
Financing Receivable, Nonaccrual	28,071	29,169
Residential Portfolio Segment [Member] \| Conventional Residential Mortgage Loans [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,767,996	2,758,359
Residential Portfolio Segment [Member] \| Conventional Residential Mortgage Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	0	0
Residential Portfolio Segment [Member] \| Conventional Residential Mortgage Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	24,963	25,985
Residential Portfolio Segment [Member] \| FHA/VA Government-Guaranteed Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	88,339	88,720
Nonaccrual Loans with No ACL	0	0
Loans Past Due 90 days or more and Still Accruing	15,532	15,776
Financing Receivable, Nonaccrual	0	0
Residential Portfolio Segment [Member] \| FHA/VA Government-Guaranteed Loans [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	70,773	70,781
Residential Portfolio Segment [Member] \| FHA/VA Government-Guaranteed Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	0	0
Residential Portfolio Segment [Member] \| FHA/VA Government-Guaranteed Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,034	2,163
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	195,267	265,568
Nonaccrual Loans with No ACL	956	956
Loans Past Due 90 days or more and Still Accruing	67	0
Financing Receivable, Nonaccrual	5,414	5,536
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	189,786	260,032
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	0	0
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	0	0
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,627,113	2,554,252
Nonaccrual Loans with No ACL	4,558	952
Loans Past Due 90 days or more and Still Accruing	540	933
Financing Receivable, Nonaccrual	7,442	8,382
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,617,658	2,544,283
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	1,265	141
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	208	513
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	3,694,843	3,688,358
Nonaccrual Loans with No ACL	12,447	13,752
Loans Past Due 90 days or more and Still Accruing	1,248	2,730
Financing Receivable, Nonaccrual	27,100	28,042
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	3,665,543	3,653,509
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	636	1,514
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	316	2,563
Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	3,658,956	3,708,876
Consumer Portfolio Segment [Member] \| Auto loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,023,928	2,043,011
Nonaccrual Loans with No ACL	942	631
Loans Past Due 90 days or more and Still Accruing	0	0
Financing Receivable, Nonaccrual	12,483	14,665
Consumer Portfolio Segment [Member] \| Auto loans [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	1,962,478	1,952,600
Consumer Portfolio Segment [Member] \| Auto loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	42,189	63,085
Consumer Portfolio Segment [Member] \| Auto loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	6,778	12,661
Consumer Portfolio Segment [Member] \| Finance Leases [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	881,802	892,039
Nonaccrual Loans with No ACL	143	100
Loans Past Due 90 days or more and Still Accruing	0	0
Financing Receivable, Nonaccrual	4,235	3,510
Consumer Portfolio Segment [Member] \| Finance Leases [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	861,882	871,810
Consumer Portfolio Segment [Member] \| Finance Leases [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	13,141	14,049
Consumer Portfolio Segment [Member] \| Finance Leases [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,544	2,670
Consumer Portfolio Segment [Member] \| Personal Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	330,904	335,156
Nonaccrual Loans with No ACL	0	0
Loans Past Due 90 days or more and Still Accruing	0	0
Financing Receivable, Nonaccrual	1,517	1,792
Consumer Portfolio Segment [Member] \| Personal Loans [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	323,143	325,474
Consumer Portfolio Segment [Member] \| Personal Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	4,125	5,185
Consumer Portfolio Segment [Member] \| Personal Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,119	2,705
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	280,364	293,088
Nonaccrual Loans with No ACL	0	0
Loans Past Due 90 days or more and Still Accruing	6,033	6,405
Financing Receivable, Nonaccrual	0	0
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	267,401	278,938
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	4,205	4,479
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	2,725	3,266
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	141,958	145,582
Nonaccrual Loans with No ACL	0	0
Loans Past Due 90 days or more and Still Accruing	0	0
Financing Receivable, Nonaccrual	1,482	1,467
Consumer Portfolio Segment [Member] \| Other Loans [Member] \| Current [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	137,204	140,117
Consumer Portfolio Segment [Member] \| Other Loans [Member] \| 30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	1,875	2,157
Consumer Portfolio Segment [Member] \| Other Loans [Member] \| 60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment	$ 1,397	$ 1,841

Amortized cost excluding accrued interest, of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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

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