Investment in Unconsolidated Joint Ventures (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013
SUMMARY OF FINANCIAL POSITION:
Total Assets	$ 661,206			$ 657,384
Total Debt	417,995			428,153
Total Equity	216,907			210,460
Company's Investment	87,617			84,322
SUMMARY OF OPERATIONS:
Total Revenues	78,230		113,003
Net Income (Loss)	13,976		68,750
Income (Loss) from Equity Method Investments Gross of Impairment Charges	5,343		65,862
Terminus Office Holdings [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	291,415			297,815
Total Debt	214,228			215,942
Total Equity	62,481			69,867
Company's Investment	32,157			35,885
SUMMARY OF OPERATIONS:
Total Revenues	29,354		23,842
Net Income (Loss)	314		(219)
Income (Loss) from Equity Method Investments Gross of Impairment Charges	134		(110)
EP I LLC [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	86,059			88,130
Total Debt	58,029			57,092
Total Equity	26,671			29,229
Company's Investment	23,401			25,319
SUMMARY OF OPERATIONS:
Total Revenues	9,024		5,499
Net Income (Loss)	2,102		(348)
Income (Loss) from Equity Method Investments Gross of Impairment Charges	1,577		(261)
EP II LLC [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	33,048			12,644
Total Debt	3,608			1
Total Equity	24,969			11,695
Company's Investment	19,773			9,566
Cousins Watkins LLC [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	50,226			51,653
Total Debt	27,278			27,710
Total Equity	21,775			23,081
Company's Investment	17,522			17,213
SUMMARY OF OPERATIONS:
Total Revenues	3,801		4,297
Net Income (Loss)	217		16
Income (Loss) from Equity Method Investments Gross of Impairment Charges	1,702		1,738
Charlotte Gateway Village, LLC [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	131,937			135,966
Total Debt	39,852			52,408
Total Equity	90,101			82,373
Company's Investment	11,226			11,252
SUMMARY OF OPERATIONS:
Total Revenues	25,079		25,079
Net Income (Loss)	8,635		7,931
Income (Loss) from Equity Method Investments Gross of Impairment Charges	882		882
Temco Associates, LLC [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	7,910			8,474
Total Debt	0			0
Total Equity	7,672			8,315
Company's Investment	3,659			4,083
SUMMARY OF OPERATIONS:
Total Revenues	793		437
Net Income (Loss)	157		48
Income (Loss) from Equity Method Investments Gross of Impairment Charges	(24)		(12)
CL Realty, L.L.C. [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	7,389			7,602
Total Debt	0			0
Total Equity	7,220			7,374
Company's Investment	3,614			3,704
SUMMARY OF OPERATIONS:
Total Revenues	1,240		1,246
Net Income (Loss)	846		801
Income (Loss) from Equity Method Investments Gross of Impairment Charges	410		392
Wildwood Associates
SUMMARY OF FINANCIAL POSITION:
Total Assets	21,101			21,127
Total Debt	0			0
Total Equity	20,997			21,121
Company's Investment	(1,739)	[1]		(1,689)	[1]
SUMMARY OF OPERATIONS:
Total Revenues	29		0
Net Income (Loss)	(125)		(126)
Income (Loss) from Equity Method Investments Gross of Impairment Charges	(50)		(63)
Crawford Long CPI LLC [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	30,876			32,042
Total Debt	75,000			75,000
Total Equity	(46,183)			(44,295)
Company's Investment	(21,997)	[1]		(21,071)	[1]
SUMMARY OF OPERATIONS:
Total Revenues	8,905		8,826
Net Income (Loss)	2,075		2,134
Income (Loss) from Equity Method Investments Gross of Impairment Charges	1,062		1,028
CF Murfreesboro Associates [Member]
SUMMARY OF OPERATIONS:
Total Revenues	0		8,079
Net Income (Loss)	0		48,969
Income (Loss) from Equity Method Investments Gross of Impairment Charges	(390)		23,562
Cp Venture Five LLC [Member]
SUMMARY OF OPERATIONS:
Total Revenues	0		20,192
Net Income (Loss)	0		3,056
Income (Loss) from Equity Method Investments Gross of Impairment Charges	0		17,146
CP Venture Two LLC [Member]
SUMMARY OF OPERATIONS:
Total Revenues	0		12,965
Net Income (Loss)	0		7,035
Income (Loss) from Equity Method Investments Gross of Impairment Charges	0		21,592
MSREF Terminus Two Hundred LLC [Member]
SUMMARY OF OPERATIONS:
Total Revenues	0		1,268
Net Income (Loss)	0		(172)
Income (Loss) from Equity Method Investments Gross of Impairment Charges	0		(28)
Other Equity Method Investee [Member]
SUMMARY OF FINANCIAL POSITION:
Total Assets	1,245			1,931
Total Debt	0			0
Total Equity	1,204			1,700
Company's Investment	1			60
SUMMARY OF OPERATIONS:
Total Revenues	5		1,273
Net Income (Loss)	(245)		(375)
Income (Loss) from Equity Method Investments Gross of Impairment Charges	$ 40		$ (4)

[1] Negative balances are included in deferred income on the balance sheets.