Parent Company only Condensed Financial Information - Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed statements of income
Interest expense	$ (1,708)	$ (1,634)	$ (1,174)	$ (871)	$ (867)	$ (826)	$ (760)	$ (758)	$ (5,387)	$ (3,211)	$ (2,422)
Income (loss) before income taxes and equity in net income of subsidiary bank	13,977	13,832	12,018	10,472	11,646	10,819	11,672	9,832	50,299	43,969	26,601
Equity in net income of subsidiary bank:
Income tax benefit	(12,719)	(5,249)	(4,569)	(3,934)	(4,431)	(4,054)	(4,377)	(3,726)	(26,471)	(16,588)	(10,104)
Net income	$ 1,258	$ 8,583	$ 7,449	$ 6,538	7,215	6,765	7,295	6,106	23,828	27,381	16,497
Dividends and discount accretion on preferred stock						(504)	(504)	(504)		(1,512)	(1,792)
Net income available to common shareholders					$ 7,215	$ 6,261	$ 6,791	$ 5,602	23,828	25,869	14,705
HCC (Parent)
Condensed statements of income
Dividend from subsidiary bank									16,000	18,000
Other Income									114
Interest expense									(1,394)	(11)	(18)
Other expenses									(2,270)	(2,568)	(2,705)
Income (loss) before income taxes and equity in net income of subsidiary bank									12,450	15,421	(2,723)
Equity in net income of subsidiary bank:
Net income of subsidiary bank									10,078	10,897	18,081
Income tax benefit									1,300	1,063	1,139
Net income									23,828	27,381	16,497
Dividends and discount accretion on preferred stock										(1,512)	(1,792)
Net income available to common shareholders									$ 23,828	$ 25,869	$ 14,705