Investment in Unconsolidated Joint Ventures (Cousins Watkins LLC) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012 Loan	Dec. 31, 2010 Loan
Schedule of Equity Method Investments [Line Items]
Variable rate basis	LIBOR
Basis spread on variable rate (percent)	1.50%
Cousins Watkins LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate cash contribution of Company in joint venture		$ 14,900,000
Number of mortgage loans obtained by joint venture (loans)		4
Mortgage loans on real estate maximum borrowing capacity		33,500,000
Maturity date of mortgage loans	Jan. 01, 2016
Extension of mortgage loans maturity, conditions	two, one-year terms, provided certain conditions are met
Percentage of loans guaranteed by Company (percent)	25.00%
Number of loans guaranteed by company (loans)	2
Internal rate of return on project (percent)	16.00%
Cash balance of joint venture	811,000
Retail [Member] | Cousins Watkins LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of real estate properties owned by venture (properties)		4
Four Loans [Member] | Cousins Watkins LLC [Member]
Schedule of Equity Method Investments [Line Items]
Outstanding balance of mortgage loan	28,200,000
Mortgages [Member] | Cousins Watkins LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate amount of loans guaranteed by Company	$ 4,100,000
Minimum [Member] | Cousins Watkins LLC [Member]
Schedule of Equity Method Investments [Line Items]
Basis spread on variable rate (percent)	2.65%
Maximum [Member] | Cousins Watkins LLC [Member]
Schedule of Equity Method Investments [Line Items]
Basis spread on variable rate (percent)	2.85%
LIBOR [Member]
Schedule of Equity Method Investments [Line Items]
Variable rate basis	LIBOR
Basis spread on variable rate (percent)	1.00%
LIBOR [Member] | Cousins Watkins LLC [Member]
Schedule of Equity Method Investments [Line Items]
Variable rate basis	LIBOR