Organization (Details) ft² in Thousands	3 Months Ended
	Mar. 31, 2020 ft² property
Real Estate Properties [Line Items]
Square feet of real estate | ft²	6,300
Percent of leased office space of owned properties	97.60%
Columbia Operating Partnership
Real Estate Properties [Line Items]
General partner and majority owner, percentage	97.20%
Office Building
Real Estate Properties [Line Items]
Number of real estate properties	15
Number of properties under development	4
Asset and Property Management Services Office Space
Real Estate Properties [Line Items]
Square feet of real estate | ft²	8,000
Wholly Owned Properties | Office Building
Real Estate Properties [Line Items]
Number of real estate properties	11
Unconsolidated Properties | Office Building
Real Estate Properties [Line Items]
Number of real estate properties	8