Noncontrolling Interests (Details) $ / shares in Units, ft² in Thousands, $ in Thousands		3 Months Ended
	Jan. 24, 2020 property $ / shares shares	Mar. 31, 2020 USD ($) ft²	Dec. 31, 2019 USD ($)
Noncontrolling Interest [Line Items]
Total assets		$ 4,400,991	$ 4,244,945
Total liabilities		$ 1,776,604	$ 1,616,328
Square feet of real estate | ft²		6,300
Columbia Operating Partnership
Noncontrolling Interest [Line Items]
Total assets		$ 4,300,000
Total liabilities		1,900,000
101 Franklin Street
Noncontrolling Interest [Line Items]
Total assets		5,100
Total liabilities		$ 3,000
Square feet of real estate | ft²		235
Preferred OP Units
Noncontrolling Interest [Line Items]
Vesting period	4 years
Conversion rate of Preferred OP Units | property	1
Normandy Acquisition | Preferred OP Units
Noncontrolling Interest [Line Items]
Number of shares to be issued for acquisition (in shares) | shares	3,264,151
Liquidation preference (in dollars per share) | $ / shares	$ 26.50
Vesting period	4 years
Variable Interest Entity, Primary Beneficiary | Columbia Operating Partnership
Noncontrolling Interest [Line Items]
Variable interest entity percentage		97.20%
Variable Interest Entity, Primary Beneficiary | 101 Franklin Street
Noncontrolling Interest [Line Items]
Variable interest entity percentage		92.50%