PARENT COMPANY FINANCIAL INFORMATION - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net income	$ 52,505	$ 43,745	$ 21,225
Adjustments to reconcile net income to net cash used in operating activities:
Restricted stock expense	2,352	1,661	1,154
Net cash provided by operating activities	51,185	44,700	31,500
Cash flows from investing activities:
Net cash used in investing activities	(259,128)	(62,682)	(8,808)
Cash flows from financing activities:
Dividends paid on common stock	(8,589)	(5,190)	(2,557)
Common stock repurchased	(8,067)	(5,229)	0
Net proceeds from issuance of stock	0	0	(237)
Net cash provided by financing activities	601,633	27,739	44,493
Parent Company [Member]
Cash flows from operating activities:
Net income	52,505	43,745	21,225
Adjustments to reconcile net income to net cash used in operating activities:
Equity in undistributed income of Subsidiary	(41,490)	(713)	(13,006)
Restricted stock expense	2,352	1,661	1,154
Other, net	329	1,185	1,364
Net cash provided by operating activities	13,696	45,878	10,737
Cash flows from investing activities:
Investment in subsidiary bank		0	(27,000)
Net outlays for acquisitions	1,726	(32,363)	(47,041)
Net cash used in investing activities	1,726	(32,363)	(74,041)
Cash flows from financing activities:
Dividends paid on common stock	(8,589)	(5,190)	(2,557)
Repurchase of restricted stock for payment of taxes	(494)	(63)	(23)
Common stock repurchased	(8,067)	(5,229)	0
Net proceeds from issuance of stock		0	(237)
Proceeds (repayment) of borrowed funds	(707)	(173)	(16,000)
Issuance of subordinated debt	63,725	0	64,766
Net cash provided by financing activities	45,868	(10,655)	45,949
Net increase (decrease) in cash and cash equivalents	61,290	2,860	(17,355)
Cash and cash equivalents at beginning of year	5,941	3,081	20,436
Cash and cash equivalents at end of year	$ 67,231	$ 5,941	$ 3,081