Acquired Leases Intangibles (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Document Fiscal Year Focus		2015
Acquired lease intangible assets, net of amortization		$ 105,380	$ 52,365
Finite-Lived Intangible Assets, Gross		151,019	88,477
Finite-Lived Intangible Liabilities, Accumulated Accretion		(17,555)	(13,993)
Accumulated amortization		(45,639)	(36,112)
Finite-Lived Intangible Assets, Amortization Expense		$ 11,442	12,183	$ 8,709
Weighted Average Accretion Period of Intangible Liabilities (in years)		13 years 2 months 12 days
Acquired lease intangible liability accretion		$ 4,155	4,590	3,726
In-place leases, net
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		$ 77,691	71,696
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life (in years)		6 years 2 months 12 days
Finite-Lived Intangible Assets, Amortization Expense		$ 9,141	10,365	7,441
Above-market leases, net
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		$ 14,841	15,020
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life (in years)	[1]	6 years 7 months 6 days
Finite-Lived Intangible Assets, Amortization Expense	[1]	$ 1,950	1,795	1,246
Above-market ground leases, net
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		$ 58,487	1,761
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life (in years)	[1]	58 years 2 months 12 days
Finite-Lived Intangible Assets, Amortization Expense	[1]	$ 351	23	$ 22
Partnership Interest [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired lease intangible assets, net of amortization		105,380	52,365
Acquired lease intangible liabilities, net		42,034	32,143
Accumulated amortization		45,639	36,112
Acquired Lease Intangible Liabilities [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired lease intangible liabilities, net		$ 59,589	$ 46,136

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