NOTE 8 - BUSINESS SEGMENT INFORMATION - Selected Financial Information on the Company's Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Total revenue	$ 88,849			$ 76,723			$ 230,303	$ 212,063
Net interest income	44,581			40,719			123,243	115,640
Provision for loan/lease losses	20,342			2,012			48,624	6,087
Net income (loss)	17,344	$ 13,739	$ 11,228	15,095	$ 13,504	$ 12,918	42,311	41,517
Goodwill	74,066			77,748			74,066	77,748	$ 74,748
Intangibles	11,902			15,529			11,902	15,529	14,970
Total assets	5,864,560			5,292,382			5,864,560	5,292,382	$ 4,909,050
Intersegment Eliminations [Member]
Total revenue	(21,839)			(22,036)			(55,342)	(54,563)
Net interest income	280						758
Net income (loss)	(21,483)			(19,280)			(54,157)	(50,897)
Total assets	(850,766)			(619,830)			(850,766)	(619,830)
Commercial Banking | QCBT | Operating Segments [Member]
Total revenue	20,856			21,230			60,083	60,148
Net interest income	16,648			13,357			46,728	38,129
Provision for loan/lease losses	7,861			948			18,583	2,941
Net income (loss)	2,455			4,870			10,664	13,560
Goodwill	3,223			3,223			3,223	3,223
Total assets	2,205,934			1,642,950			2,205,934	1,642,950
Commercial Banking | CRBT | Operating Segments [Member]
Total revenue	43,331			25,707			99,938	68,526
Net interest income	14,432			11,478			38,638	32,671
Provision for loan/lease losses	8,878			150			18,288	875
Net income (loss)	13,221			7,900			30,178	19,928
Goodwill	14,980			14,980			14,980	14,980
Intangibles	2,313			2,810			2,313	2,810
Total assets	2,012,182			1,592,896			2,012,182	1,592,896
Commercial Banking | CSB | Operating Segments [Member]
Total revenue	11,033			11,596			30,836	30,596
Net interest income	8,593			8,894			23,631	23,154
Provision for loan/lease losses	2,493			150			7,268	451
Net income (loss)	1,867			3,482			3,496	7,845
Goodwill	9,888			9,888			9,888	9,888
Intangibles	3,474			4,154			3,474	4,154
Total assets	937,016			801,596			937,016	801,596
Commercial Banking | SFCB | Operating Segments [Member]
Total revenue	10,266			8,351			28,490	23,396
Net interest income	6,159			5,056			18,002	15,707
Provision for loan/lease losses	1,110			276			4,485	1,261
Net income (loss)	2,869			2,116			6,974	5,848
Goodwill	45,975			45,975			45,975	45,975
Intangibles	6,115			7,034			6,115	7,034
Total assets	803,478			693,898			803,478	693,898
Wealth Management Segment [Member] | Operating Segments [Member]
Total revenue	3,545			4,122			11,211	12,599
Net income (loss)	1,053			926			2,860	2,667
Other Segments | Operating Segments [Member]
Total revenue	21,657			27,753			55,087	71,361
Net interest income	(1,531)			1,934			(4,514)	5,979
Provision for loan/lease losses				488				559
Net income (loss)	17,362			15,081			42,296	42,566
Goodwill				3,682				3,682
Intangibles				1,531				1,531
Total assets	$ 756,716			$ 1,180,872			$ 756,716	$ 1,180,872