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Amount of gain (loss) on sale of financing receivable.

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LOANS HELD FOR INVESTMENT - Additional Information IV (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 13,091,077,000		$ 13,125,356,000
Recoveries	6,054,000	$ 6,700,000
Florida [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,545,362,000		2,498,164,000
GNMA [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pooled amount	41,600,000	42,200,000
Recognized gain on sale	2,400,000	1,100,000
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,914,898,000		2,908,302,000
Recoveries	354,000	217,000
Residential Portfolio Segment [Member] \| Florida [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	536,510,000		530,698,000
Residential Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,886,827,000		2,879,133,000
Residential Portfolio Segment [Member] \| Performing Financial Instruments [Member] \| Florida [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	525,237,000		519,573,000
Residential Portfolio Segment [Member] \| Performing Financial Instruments [Member] \| GSEs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans sold	0	4,100,000
Gain from sale of loans		200,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,694,843,000		3,688,358,000
Recoveries	81,000	154,000
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member] \| Florida [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,200,142,000		1,169,356,000
Purchased loans	35,700,000	15,000,000.0
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,658,956,000		3,708,876,000
Recoveries	5,566,000	6,275,000
Consumer Portfolio Segment [Member] \| Florida [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	5,856,000		5,857,000
Consumer Portfolio Segment [Member] \| Performing Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,639,239,000		3,687,442,000
Repurchase Option Program [Member] \| Past Due [Member] \| Residential Portfolio Segment [Member] \| GNMA [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	6,700,000		$ 6,700,000
Purchased loans	$ 400,000	200,000
Bulk Sale Of Fully Charged-Off Loans [Member] \| Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recoveries		$ 2,400,000