Basis of Presentation and Summary of Significant Accounting Policies (Narrative) (Details) $ / shares in Units, $ in Thousands, ft² in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2016 USD ($) state $ / shares	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Jun. 30, 2016 USD ($) state $ / shares	Jun. 30, 2015 USD ($)	Jul. 01, 2016 ft² property state	Apr. 28, 2016 USD ($) $ / shares	Dec. 31, 2015 USD ($) $ / shares
Entity Information [Line Items]
Number of states in which office properties are located | state	6			6
Percentage of noncontrolling interest in operating partnerships	4.10%			4.10%
Common stock, par value (in dollars per share) | $ / shares	$ 0.001			$ 0.001				$ 0.001
Possible termination fee if the Merger Agreement is terminated							$ 65,000
Possible expense incurred if the Merger Agreement is terminated							$ 20,000
Impairment loss on real estate	$ 0	$ 4,400	$ 1,000	$ 0	$ 5,400
Parkway Properties LP
Entity Information [Line Items]
Company's Ownership %	95.90%			95.90%
Variable Interest Entity, Primary Beneficiary | Fund II
Entity Information [Line Items]
Total assets of consolidated VIE	$ 544,600			$ 544,600				$ 536,500
Total liabilities of consolidated VIE	$ 299,300			$ 299,300				$ 294,100
Common Stock | Cousins Properties Inc.
Entity Information [Line Items]
Common stock, par value (in dollars per share) | $ / shares							$ 1.00
Common Stock | Parkway Properties Inc. | Cousins Properties Inc.
Entity Information [Line Items]
Possible conversion right to existing shareholders of Parkway Properties Inc							1.63
Limited Voting Preferred Stock | Cousins Properties Inc.
Entity Information [Line Items]
Preferred stock, par value (in dollars per share) | $ / shares							$ 1.00
Limited Voting Preferred Stock | Parkway Properties Inc. | Cousins Properties Inc.
Entity Information [Line Items]
Possible conversion right to existing shareholders of Parkway Properties Inc							1.63
Subsequent Event
Entity Information [Line Items]
Number of office and parking properties | property						34
Number of states in which office properties are located | state						6
Net rentable area (sqft) | ft²						14.0
Subsequent Event | Subsidiaries
Entity Information [Line Items]
Net rentable area (sqft) | ft²						2.7