Investments in Real Estate and Real Estate Under Construction Summary of properties to be acquired (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014
Business Acquisition [Line Items]
Estimated acquisition cost	$ 40,025
Auburn Hills, Michigan [Member] | Office Building [Member]
Business Acquisition [Line Items]
Estimated acquisition cost	$ 40,025
Lease Term (Years)	14 years