Intangible Assets and Liabilities - Summary of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Assets:
Gross	$ 490,329	$ 478,914
Accumulated amortization	(219,334)	(182,149)
Total	$ 270,995	$ 296,765
Weighted Average Remaining Amortization in Years	16 years 7 months 6 days	15 years 2 months 12 days
Liabilities:
Gross	$ 33,822	$ 18,045
Accumulated amortization	(7,211)	(5,620)
Total	$ 26,611	$ 12,425
Weighted Average Remaining Amortization in Years	38 years	17 years 1 month 6 days
Below market leases
Liabilities:
Gross	$ 22,240	$ 14,188
Weighted Average Remaining Amortization in Years	27 years 2 months 12 days	11 years 6 months
Above market leasehold interests
Liabilities:
Gross	$ 11,582	$ 3,857
Weighted Average Remaining Amortization in Years	53 years 8 months 12 days	32 years 1 month 6 days
In place leases
Assets:
Gross	$ 249,824	$ 231,370
Weighted Average Remaining Amortization in Years	11 years	8 years 9 months 18 days
Tenant relationships
Assets:
Gross	$ 180,925	$ 187,918
Weighted Average Remaining Amortization in Years	10 years 4 months 24 days	10 years 3 months 18 days
Above market leases
Assets:
Gross	$ 24,974	$ 26,676
Weighted Average Remaining Amortization in Years	6 years	5 years 6 months
Below market leasehold interests
Assets:
Gross	$ 34,606	$ 32,950
Weighted Average Remaining Amortization in Years	63 years	67 years 3 months 18 days