Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2021	Jul. 26, 2021
Document Information [Line Items]
Entity Central Index Key	0000702513
Entity Registrant Name	Bank of Commerce Holdings
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2021
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
Document Transition Report	false
Entity File Number	0-25135
Entity Incorporation, State or Country Code	CA
Entity Tax Identification Number	94-2823865
Entity Address, Address Line One	555 Capitol Mall, Suite 1255
Entity Address, City or Town	Sacramento
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95814
City Area Code	800
Local Phone Number	421-2575
Title of 12(b) Security	Common Stock
Trading Symbol	BOCH
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		16,894,391