Borrowings - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Secured lines of credit	$ 4,000,000
FHLB borrowings	$ 245,000	$ 50,000
Average interest rate on Federal Home Loan Bank borrowings	4.20%
Weighted average interest rate on balances outstanding	4.19%
Subordinated Debt
Debt Instrument [Line Items]
Debt		$ 25,000	$ 12,300
Interest rate		3.375%	5.50%
Contractual Interest Rate		2.03%	5.33%
Fair value adjustment		$ (3,900)	$ 400
Federal Reserve Bank Advances
Debt Instrument [Line Items]
Secured lines of credit	$ 2,600,000
Federal Home Loan Bank Advances
Debt Instrument [Line Items]
Secured lines of credit	1,400,000
Trust I & II
Debt Instrument [Line Items]
Junior subordinated deferrable interest notes issued	41,200
SBCF Statutory Trust III
Debt Instrument [Line Items]
Junior subordinated deferrable interest notes issued	$ 12,400
Contractual Interest Rate	1.61%