Investment in Unconsolidated Joint Ventures (Crawford Long—CPI, LLC) (Details) (Crawford Long CPI LLC [Member], USD $)	3 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Mortgage Loans on Real Estate, Final Maturity Date		Jun. 01, 2023
Proceeds from Issuance of Long-term Debt	$ 14,300,000
Cash balance of joint venture		2,500,000
Secured Mortgage Note Payable [Member]
Schedule of Equity Method Investments [Line Items]
Debt Instrument, Face Amount		$ 75,000,000
Interest rate on mortgage loan (percent)		3.50%
Midtown Atlanta Georgia [Member]
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (square feet)		358,000
Emory University [Member]
Schedule of Equity Method Investments [Line Items]
Ownership Percentage of Partner in Joint Venture		50.00%