ALLOWANCE FOR LOAN LOSSES: (Details 5) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	$ 31,590	$ 16,682
Current	2,634,852	1,944,526
BALANCE AT END OF YEAR	2,666,442	1,961,208
Commercial & Industrial
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	5,030	1,782
Current	594,925	518,239
BALANCE AT END OF YEAR	599,955	520,021
Farmland
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	2,221	2,659
Current	137,730	104,981
BALANCE AT END OF YEAR	139,951	107,640
Non Farm, Non Residential
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	3,853	57
Current	398,854	188,706
BALANCE AT END OF YEAR	402,707	188,763
Agriculture
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	405	388
Current	162,794	148,345
BALANCE AT END OF YEAR	163,199	148,733
All Other Commercial
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	109	33
Current	288,845	208,633
BALANCE AT END OF YEAR	288,954	208,666
First Liens
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	9,202	5,267
Current	375,924	231,684
BALANCE AT END OF YEAR	385,126	236,951
Home Equity
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	221	273
Current	70,813	39,378
BALANCE AT END OF YEAR	71,034	39,651
Junior Liens
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	564	420
Current	54,533	49,111
BALANCE AT END OF YEAR	55,097	49,531
Multifamily
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	0
Current	148,282	109,609
BALANCE AT END OF YEAR	148,282	109,609
All Other Residential
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	1,972	24
Current	22,510	9,146
BALANCE AT END OF YEAR	24,482	9,170
Motor Vehicle
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	7,741	5,552
Current	347,950	309,238
BALANCE AT END OF YEAR	355,691	314,790
All Other Consumer
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	272	227
Current	31,692	27,456
BALANCE AT END OF YEAR	31,964	27,683
30 to 59 Days Past Due
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	21,801	10,229
30 to 59 Days Past Due | Commercial & Industrial
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	2,885	1,017
30 to 59 Days Past Due | Farmland
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	132	515
30 to 59 Days Past Due | Non Farm, Non Residential
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	3,749	0
30 to 59 Days Past Due | Agriculture
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	277	41
30 to 59 Days Past Due | All Other Commercial
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	30
30 to 59 Days Past Due | First Liens
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	6,452	3,365
30 to 59 Days Past Due | Home Equity
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	124	155
30 to 59 Days Past Due | Junior Liens
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	384	132
30 to 59 Days Past Due | Multifamily
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	0
30 to 59 Days Past Due | All Other Residential
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	1,082	0
30 to 59 Days Past Due | Motor Vehicle
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	6,488	4,766
30 to 59 Days Past Due | All Other Consumer
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	228	208
60 to 89 Days Past Due
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	3,421	1,718
60 to 89 Days Past Due | Commercial & Industrial
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	766	420
60 to 89 Days Past Due | Farmland
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	8
60 to 89 Days Past Due | Non Farm, Non Residential
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	104	0
60 to 89 Days Past Due | Agriculture
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	128	0
60 to 89 Days Past Due | All Other Commercial
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	3
60 to 89 Days Past Due | First Liens
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	1,292	429
60 to 89 Days Past Due | Home Equity
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	63	8
60 to 89 Days Past Due | Junior Liens
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	43	225
60 to 89 Days Past Due | Multifamily
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	0
60 to 89 Days Past Due | All Other Residential
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	9
60 to 89 Days Past Due | Motor Vehicle
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	983	609
60 to 89 Days Past Due | All Other Consumer
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	42	7
Greater than 90 Days Past Due
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	6,368	4,735
Greater than 90 Days Past Due | Commercial & Industrial
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	1,379	345
Greater than 90 Days Past Due | Farmland
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	2,089	2,136
Greater than 90 Days Past Due | Non Farm, Non Residential
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	57
Greater than 90 Days Past Due | Agriculture
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	347
Greater than 90 Days Past Due | All Other Commercial
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	109	0
Greater than 90 Days Past Due | First Liens
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	1,458	1,473
Greater than 90 Days Past Due | Home Equity
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	34	110
Greater than 90 Days Past Due | Junior Liens
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	137	63
Greater than 90 Days Past Due | Multifamily
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	0	0
Greater than 90 Days Past Due | All Other Residential
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	890	15
Greater than 90 Days Past Due | Motor Vehicle
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	270	177
Greater than 90 Days Past Due | All Other Consumer
Aging of recorded investment in loans by past due category and class of loans
Total Past Due	$ 2	$ 12