Investment in Unconsolidated Joint Ventures (Cousins Watkins LLC) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Operating distributions from unconsolidated joint ventures	$ 10,296	$ 67,101	$ 37,379
Cousins Watkins LLC [Member]
Schedule of Equity Method Investments [Line Items]
Operating distributions from unconsolidated joint ventures	19,800
Gain (Loss) on Sale of Equity Investments	$ 2,200