Business Combinations - Purchase Price (Details) $ / shares in Units, shares in Thousands, $ in Thousands				12 Months Ended
	Oct. 01, 2025 USD ($) $ / shares shares	Jul. 11, 2025 USD ($) $ / shares shares	Jan. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2023 USD ($)
Business Combination [Line Items]
Fair value of Professional options converted				$ 10,300
Villages Bancorporation, Inc.
Business Combination [Line Items]
Number of shares receiving stock (in shares) | shares	550
Per share exchange ratio for shares receiving stock	38.5000
Multiplied by common stock price per share (in dollars per share) | $ / shares	$ 30.50
Value of SBCF stock issued	$ 645,785
Number of shares receiving cash (in shares) | shares	183
Per share cash consideration for shares receiving cash (in dollars per share) | $ / shares	$ 1,000
Cash consideration paid to shareholders, including cash paid for fractional shares	$ 183,360
Total purchase price	$ 829,145
Preferred stock to common stock ratio	0.001
Villages Bancorporation, Inc. | Common Stock
Business Combination [Line Items]
Number of shares of SBCF stock issued (in shares) | shares	9,923
Villages Bancorporation, Inc. | Preferred Stock
Business Combination [Line Items]
Number of shares of SBCF stock issued (in shares) | shares	11
Heartland Bancshares, Inc
Business Combination [Line Items]
Number of shares receiving stock (in shares) | shares		378
Per share exchange ratio for shares receiving stock		4.9263
Number of shares of SBCF stock issued (in shares) | shares		1,862
Multiplied by common stock price per share (in dollars per share) | $ / shares		$ 29.29
Value of SBCF stock issued		$ 54,547
Number of shares receiving cash (in shares) | shares		378
Per share cash consideration for shares receiving cash (in dollars per share) | $ / shares		$ 147.10
Cash consideration paid to shareholders, including cash paid for fractional shares		$ 55,623
Cash paid to option holders		1,054
Total purchase price		$ 111,224
Professional Holding Corp.
Business Combination [Line Items]
Number of shares receiving stock (in shares) | shares			14,358
Per share exchange ratio for shares receiving stock			0.8909
Number of shares of SBCF stock issued (in shares) | shares			12,792
Multiplied by common stock price per share (in dollars per share) | $ / shares			$ 32.11
Value of SBCF stock issued			$ 410,738
Cash paid for fractional shares			5
Fair value of Professional options converted			10,304
Total purchase price			$ 421,047