Real Estate Investments (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Payments for Deposits on Real Estate Acquisitions		$ (2,300)
Document Fiscal Year Focus		2015
Off-market Lease, Unfavorable		13 years 2 months 12 days
Fairfield Portfolio [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage		80.00%
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value		$ 15,400
East San Marco [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
Payment to acquire business		$ 5,200
Indian Springs [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain		$ 18,300
Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value		$ 14,100
Fair Value Inputs, Cap Rate		6.07%
Fair Value Inputs, Long-term Revenue Growth Rate		3.00%
Fair Value Inputs, Discount Rate		7.00%
Wholly Owned Properties [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross		$ 86,657	$ 282,728
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums		42,799	103,187
Acquired Finite-lived Intangible Asset, Amount		64,482	20,532
Acquired Finite Lived Intangible Liability Amount		$ 14,039	$ 10,802
Wholly Owned Properties [Member] | University Commons [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition		Sep. 01, 2015
Business Acquisition, Name of Acquired Entity		University Commons
Business Acquisition Location, City and State		Boca Raton, FL
Business Acquisition, Property type		Operating
Payments to Acquire Businesses, Gross		$ 80,500
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums		42,799
Acquired Finite-lived Intangible Asset, Amount		64,482
Acquired Finite Lived Intangible Liability Amount		$ 14,039
Wholly Owned Properties [Member] | Persimmon Place [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Jan. 31, 2014
Business Acquisition, Name of Acquired Entity			Persimmon Place
Business Acquisition Location, City and State			Dublin, CA
Business Acquisition, Property type			Development
Payments to Acquire Businesses, Gross			$ 14,200
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			0
Acquired Finite-lived Intangible Asset, Amount			0
Acquired Finite Lived Intangible Liability Amount			$ 0
Wholly Owned Properties [Member] | CityLine Market Ph II [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition		Oct. 09, 2015
Business Acquisition, Name of Acquired Entity		CityLine Market Ph II
Business Acquisition Location, City and State		Dallas, TX
Business Acquisition, Property type		Development
Payments to Acquire Businesses, Gross		$ 2,157
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums		0
Acquired Finite-lived Intangible Asset, Amount		0
Acquired Finite Lived Intangible Liability Amount		$ 0
Wholly Owned Properties [Member] | Shops at Mira Vista [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Feb. 14, 2014
Business Acquisition, Name of Acquired Entity			Shops at Mira Vista
Business Acquisition Location, City and State			Austin, TX
Business Acquisition, Property type			Operating
Payments to Acquire Businesses, Gross			$ 22,500
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			319
Acquired Finite-lived Intangible Asset, Amount			2,329
Acquired Finite Lived Intangible Liability Amount			$ 291
Wholly Owned Properties [Member] | Northgate Ph II [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition		Dec. 29, 2015
Business Acquisition, Name of Acquired Entity		Northgate Ph II
Business Acquisition Location, City and State		Medford, OR
Business Acquisition, Property type		Development
Payments to Acquire Businesses, Gross		$ 4,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums		0
Acquired Finite-lived Intangible Asset, Amount		0
Acquired Finite Lived Intangible Liability Amount		$ 0
Wholly Owned Properties [Member] | Fairfield Portfolio [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Mar. 07, 2014
Business Acquisition, Name of Acquired Entity			Fairfield Portfolio (1)
Business Acquisition Location, City and State			Fairfield, CT
Business Acquisition, Property type			Operating
Payments to Acquire Businesses, Gross			$ 149,344
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			77,730
Acquired Finite-lived Intangible Asset, Amount			12,650
Acquired Finite Lived Intangible Liability Amount			$ 5,601
Wholly Owned Properties [Member] | Willow Oaks Crossing [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Jun. 02, 2014
Business Acquisition, Name of Acquired Entity			Willow Oaks Crossing
Business Acquisition Location, City and State			Concord, NC
Business Acquisition, Property type			Development
Payments to Acquire Businesses, Gross			$ 3,342
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			0
Acquired Finite-lived Intangible Asset, Amount			0
Acquired Finite Lived Intangible Liability Amount			$ 0
Wholly Owned Properties [Member] | Clybourn Commons [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Jul. 15, 2014
Business Acquisition, Name of Acquired Entity			Clybourn Commons
Business Acquisition Location, City and State			Chicago, IL
Business Acquisition, Property type			Operating
Payments to Acquire Businesses, Gross			$ 19,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			0
Acquired Finite-lived Intangible Asset, Amount			1,686
Acquired Finite Lived Intangible Liability Amount			$ 3,298
Wholly Owned Properties [Member] | Belmont Chase [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Sep. 10, 2014
Business Acquisition, Name of Acquired Entity			Belmont Chase
Business Acquisition Location, City and State			Ashburn, VA
Business Acquisition, Property type			Development
Payments to Acquire Businesses, Gross			$ 4,300
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			0
Acquired Finite-lived Intangible Asset, Amount			0
Acquired Finite Lived Intangible Liability Amount			$ 0
Wholly Owned Properties [Member] | City Line Market [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Sep. 19, 2014
Business Acquisition, Name of Acquired Entity			CityLine Market
Business Acquisition Location, City and State			Dallas, TX
Business Acquisition, Property type			Development
Payments to Acquire Businesses, Gross			$ 4,913
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			0
Acquired Finite-lived Intangible Asset, Amount			0
Acquired Finite Lived Intangible Liability Amount			$ 0
Wholly Owned Properties [Member] | East San Marco [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Oct. 24, 2014
Business Acquisition, Name of Acquired Entity			East San Marco (2)
Business Acquisition Location, City and State			Jacksonville, FL
Business Acquisition, Property type			Development
Payments to Acquire Businesses, Gross			$ 5,223
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			0
Acquired Finite-lived Intangible Asset, Amount			0
Acquired Finite Lived Intangible Liability Amount			$ 0
Wholly Owned Properties [Member] | The Village at La Floresta [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Dec. 04, 2014
Business Acquisition, Name of Acquired Entity			The Village at La Floresta
Business Acquisition Location, City and State			Brea, CA
Business Acquisition, Property type			Development
Payments to Acquire Businesses, Gross			$ 6,750
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			0
Acquired Finite-lived Intangible Asset, Amount			0
Acquired Finite Lived Intangible Liability Amount			$ 0
Wholly Owned Properties [Member] | Indian Springs [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition			Dec. 16, 2014
Business Acquisition, Name of Acquired Entity			Indian Springs (3)
Business Acquisition Location, City and State			Houston, TX
Business Acquisition, Property type			Operating
Payments to Acquire Businesses, Gross			$ 53,156
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Debt Assumed, Net of Premiums			25,138
Acquired Finite-lived Intangible Asset, Amount			3,867
Acquired Finite Lived Intangible Liability Amount			1,612
Leases, Acquired-in-Place [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		6 years 2 months 12 days
Above Market Lease [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	[1]	6 years 7 months 6 days
Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	[1]	58 years 2 months 12 days
Parent Company [Member]
Business Acquisition [Line Items]
Payments for Deposits on Real Estate Acquisitions		$ 2,250	0	$ 0
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain		0	18,271	0
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value		0	15,385	0
Mortgage loans assumed for the acquisition of real estate		$ 42,799	$ 103,187	$ 0
Parent Company [Member] | Leases, Acquired-in-Place [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		14 years 8 months 12 days	4 years 10 months 24 days
Parent Company [Member] | Above Market Lease [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	[1]	12 years 3 months 18 days	3 years 10 months 24 days
Parent Company [Member] | Off-Market Favorable Lease [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		57 years 4 months 24 days	41 years 2 months 12 days
Acquired Lease Intangible Liabilities [Member] | Parent Company [Member]
Business Acquisition [Line Items]
Off-market Lease, Unfavorable		18 years 1 month 6 days	12 years 8 months 12 days

[1] Amounts are recorded as a reduction to minimum rent.