Cover Page - shares	6 Months Ended
	Jun. 30, 2020	Aug. 10, 2020
Entity Information [Line Items]
Document Type	10-Q
Document Period End Date	Jun. 30, 2020
Entity Registrant Name	Cole Office & Industrial REIT (CCIT III), Inc.
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Current Fiscal Year End Date	--12-31
Entity Emerging Growth Company	true
Entity Small Business	false
Entity Ex Transition Period	true
Entity Current Report Status	Yes
Entity Shell Company	false
Entity Central Index Key	0001614976
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Class A Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		2,500,000
Class T Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		709,000