PARENT COMPANY STATEMENTS (CONDENSED BALANCE SHEETS) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Other assets	$ 28,439	$ 31,153
Total assets	4,682,976	4,290,025
LIABILITIES
Subordinated debt	30,928	30,928
STOCKHOLDERS' EQUITY	468,578	426,978	$ 392,812	$ 361,296
Total liabilities and stockholders' equity	4,682,976	4,290,025
Parent Company [Member]
ASSETS
Deposits with Lake City Bank	850	3,467
Deposits with other depository institutions	4,969	4,636
Cash	5,819	8,103
Investments in banking subsidiary	482,585	441,389
Investments in other subsidiaries	3,552	3,471
Other assets	7,789	5,206
Total assets	499,745	458,169
LIABILITIES
Dividends payable and other liabilities	239	263
Subordinated debt	30,928	30,928
STOCKHOLDERS' EQUITY	468,578	426,978
Total liabilities and stockholders' equity	$ 499,745	$ 458,169