Business Combinations - Pro-Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended		9 Months Ended
	Aug. 21, 2020	Mar. 13, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Business Acquisition, Pro Forma Information [Abstract]
Net interest income			$ 65,825	$ 67,090	$ 205,641	$ 198,748
Net income			$ 28,238	$ 27,557	$ 58,824	$ 73,238
EPS - basic (in dollars per share)			$ 0.51	$ 0.50	$ 1.08	$ 1.34
EPS - diluted (in dollars per share)			$ 0.51	$ 0.50	$ 1.07	$ 1.33
First Bank of the Palm Beaches
Business Acquisition, Pro Forma Information [Abstract]
Provision for credit losses excluded from pro-forma information		$ 1,800
Fourth Street Banking Company
Business Acquisition, Pro Forma Information [Abstract]
Provision for credit losses excluded from pro-forma information	$ 4,600