Capital and Financing Transactions - Summary of Mortgage Notes Payable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Note Balance	$ 1,218,458
Unamortized premium, net	19,878	$ 27,842
Parkway Properties
Debt Instrument [Line Items]
Monthly Payment	6,459
Note Balance	1,238,336	1,339,450
Total Wholly Owned
Debt Instrument [Line Items]
Monthly Payment	5,082
Note Balance	$ 949,034	1,037,992
Westshore Corporate Center
Debt Instrument [Line Items]
Fixed rate	2.50%
Maturity Date	May 01, 2015
Monthly Payment	$ 0
Note Balance	$ 0	14,091
Teachers Insurance and Annuity Associations (5 properties)
Debt Instrument [Line Items]
Fixed rate	6.20%
Maturity Date	Jan. 01, 2016
Monthly Payment	$ 0
Note Balance	$ 0	68,884
John Hancock Facility (2 properties)
Debt Instrument [Line Items]
Fixed rate	7.60%
Maturity Date	Jun. 01, 2016
Monthly Payment	$ 0
Note Balance	$ 0	17,398
3350 Peachtree
Debt Instrument [Line Items]
Fixed rate	7.30%
Maturity Date	Mar. 05, 2017
Monthly Payment	$ 0
Note Balance	$ 0	32,185
One Orlando Centre
Debt Instrument [Line Items]
Fixed rate	4.60%
Maturity Date	May 11, 2017
Monthly Payment	$ 265
Note Balance	$ 54,000	54,000
One Congress Plaza
Debt Instrument [Line Items]
Fixed rate	3.20%
Maturity Date	Jun. 11, 2017
Monthly Payment	$ 649
Note Balance	$ 128,000	128,000
San Jacinto Center
Debt Instrument [Line Items]
Fixed rate	3.20%
Maturity Date	Jun. 11, 2017
Monthly Payment	$ 509
Note Balance	$ 101,000	101,000
The Pointe
Debt Instrument [Line Items]
Fixed rate	4.00%
Maturity Date	Feb. 10, 2019
Monthly Payment	$ 112
Note Balance	$ 23,364	23,500
Corporate Center IV
Debt Instrument [Line Items]
Fixed rate	4.60%
Maturity Date	Apr. 08, 2019
Monthly Payment	$ 223
Note Balance	$ 35,491	36,000
Citrus Center
Debt Instrument [Line Items]
Fixed rate	6.30%
Maturity Date	Jun. 01, 2020
Monthly Payment	$ 153
Note Balance	$ 20,645	21,138
Stein Mart
Debt Instrument [Line Items]
Fixed rate	6.50%
Maturity Date	Aug. 01, 2020
Monthly Payment	$ 81
Note Balance	$ 10,778	11,041
Phoenix Tower
Debt Instrument [Line Items]
Fixed rate	3.90%
Maturity Date	Mar. 01, 2023
Monthly Payment	$ 417
Note Balance	$ 78,555	80,000
Deerwood North and South
Debt Instrument [Line Items]
Fixed rate	3.90%
Maturity Date	Apr. 01, 2023
Monthly Payment	$ 276
Note Balance	$ 84,500	84,500
Lincoln Place
Debt Instrument [Line Items]
Fixed rate	3.60%
Maturity Date	Jun. 11, 2016
Monthly Payment	$ 293
Note Balance	$ 48,030	48,670
CityWestPlace I & II
Debt Instrument [Line Items]
Fixed rate	3.50%
Maturity Date	Jul. 06, 2016
Monthly Payment	$ 738
Note Balance	$ 114,460	116,111
CityWestPlace III & IV
Debt Instrument [Line Items]
Fixed rate	4.30%
Maturity Date	Mar. 05, 2020
Monthly Payment	$ 512
Note Balance	$ 90,334	91,889
San Felipe Plaza
Debt Instrument [Line Items]
Fixed rate	4.30%
Maturity Date	Dec. 01, 2018
Monthly Payment	$ 576
Note Balance	$ 107,877	109,585
Two Buckhead Plaza
Debt Instrument [Line Items]
Fixed rate	2.60%
Maturity Date	Oct. 01, 2017
Monthly Payment	$ 278
Note Balance	52,000	0
Total Fund II
Debt Instrument [Line Items]
Monthly Payment	1,377
Note Balance	$ 269,424	273,616
3344 Peachtree | Subsidiaries
Debt Instrument [Line Items]
Fixed rate	5.30%
Maturity Date	Oct. 01, 2017
Monthly Payment	$ 485
Note Balance	$ 80,986	82,907
Hayden Ferry Lakeside I | Subsidiaries
Debt Instrument [Line Items]
Fixed rate	4.50%
Maturity Date	Jul. 25, 2018
Monthly Payment	$ 112
Note Balance	$ 21,536	21,887
Hayden Ferry Lakeside II & IV | Subsidiaries
Debt Instrument [Line Items]
Fixed rate	4.00%
Maturity Date	Jul. 25, 2018
Monthly Payment	$ 227
Note Balance	$ 46,064	46,875
Hayden Ferry Lakeside III | Subsidiaries
Debt Instrument [Line Items]
Variable rate	2.20%
Maturity Date	Jul. 25, 2018
Monthly Payment	$ 58
Note Balance	$ 31,271	481
245 Riverside | Subsidiaries
Debt Instrument [Line Items]
Fixed rate	5.20%
Maturity Date	Mar. 31, 2019
Monthly Payment	$ 0
Note Balance	$ 0	9,166
Two Ravinia | Subsidiaries
Debt Instrument [Line Items]
Fixed rate	5.00%
Maturity Date	May 20, 2019
Monthly Payment	$ 0
Note Balance	$ 0	22,100
Two Liberty Place | Subsidiaries
Debt Instrument [Line Items]
Fixed rate	5.20%
Maturity Date	Jun. 10, 2019
Monthly Payment	$ 495
Note Balance	$ 89,567	$ 90,200