Summarized Quarterly Financial Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Interest income	$ 48,548	$ 49,981	$ 50,238	$ 48,933	$ 44,348	$ 42,729	$ 39,180	$ 37,644	$ 197,700	$ 163,901	$ 142,930
Taxable equivalent adjustment	189	192	202	208	194	187	187	187
Interest income (FTE)	48,737	50,173	50,440	49,141	44,542	42,916	39,367	37,831
Interest expense	8,701	9,444	9,327	8,867	7,917	7,171	5,607	4,997	36,339	25,692	16,805
Net Interest Income	40,036	40,729	41,113	40,274	36,625	35,745	33,760	32,834
(Recovery of) provision for loan losses	(75)	274	(600)	(849)	(400)	(27)	(2,064)	181	(1,250)	(2,310)	3,006
Noninterest income	18,042	16,698	17,825	15,925	14,706	15,753	15,611	14,492	68,490	60,564	63,607
Noninterest expense	29,034	28,397	30,772	29,411	38,178	25,040	24,911	24,937	117,614	113,066	95,981
Income before income tax expense	29,119	28,756	28,766	27,637	13,553	26,485	26,524	22,208	113,487	88,017	90,745
Income tax expense	6,319	6,193	5,813	5,810	2,646	5,606	5,358	4,405	24,135	18,015	36,435
Interest Income Taxable Equivalent Adjustment - Tax	(189)	(192)	(202)	(208)	(194)	(187)	(187)	(187)
Net Income Available to Common Shareholders	22,611	22,371	22,751	21,619	10,713	20,692	20,979	17,616	89,352	70,002	54,310
Net earnings allocated to common shareholders	$ 22,409	$ 22,179	$ 22,554	$ 21,433	$ 10,623	$ 20,491	$ 20,768	$ 17,421	$ 88,546	$ 69,348	$ 53,719
Basic earnings per common share	$ 1.38	$ 1.36	$ 1.38	$ 1.31	$ 0.68	$ 1.34	$ 1.36	$ 1.13	$ 5.43	$ 4.50	$ 3.49
Diluted earnings per common share	$ 1.38	$ 1.36	$ 1.38	$ 1.30	$ 0.68	$ 1.33	$ 1.35	$ 1.13	$ 5.42	$ 4.49	$ 3.48
Basic	16,207	16,271	16,368	16,411	15,603	15,340	15,326	15,414	16,314	15,421	15,412
Average shares outstanding, diluted	16,230	16,289	16,386	16,429	15,618	15,358	15,345	15,436	16,333	15,439	15,436

Interest Income Expense Net Including Taxable Equivalent Adjustment

No definition available.

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Namespace Prefix:	chco_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Interest income, on a tax-equivalent basis. Tax-equivalent interest income is interest income plus the taxes that would have been paid had tax-exempt securities been taxable. This number attempts to enhance the comparability of the performance of assets that have different tax liabilities.

+ References

No definition available.