Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2020	Jan. 31, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	0-13660
Entity Registrant Name	Seacoast Banking Corporation of Florida
Entity Incorporation, State or Country Code	FL
Entity Tax Identification Number	59-2260678
Entity Address, Address Line One	815 Colorado Avenue,
Entity Address, City or Town	Stuart
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	34994
City Area Code	(772)
Local Phone Number	287-4000
Title of 12(b) Security	Common Stock
Trading Symbol	SBCF
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1,081,009,362
Entity Common Stock, Shares Outstanding		55,249,870
Documents Incorporated by Reference	Certain portions of the registrant’s Proxy Statement for the 2021 Annual Meeting of Shareholders (the “2021 Proxy Statement”) are incorporated by reference into Part III, Items 10 through 14 of this report. Other than those portions of the 2021 Proxy Statement specifically incorporated by reference herein pursuant to Items 10 through 14, no other portions of the 2021 Proxy Statement shall be deemed so incorporated.
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Central Index Key	0000730708