Acquired Intangible Assets and Liabilities (Schedule of Estimated Annual Amortization of Below Market Leases) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Total	$ 86,888	$ 101,114
Below-Market Leases, Net of Above-Market Leases
Finite-Lived Intangible Assets [Line Items]
Remainder of 2016	2,164
2017	7,060
2018	5,499
2019	5,659
2020	7,473
Thereafter	34,479
Total	$ 62,334