Real Estate Investments (Summary of Intangible Assets and Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Intangible assets:
Gross Carrying Amount	$ 184,806	$ 192,454
Accumulated Amortization	52,005	38,884
Net Carrying Amount	132,801	153,570
Intangible liabilities:
Gross Carrying Amount	83,827	84,837
Accumulated Amortization	9,308	6,734
Net Carrying Amount	74,519	78,103
In-place leases [Member]
Intangible assets:
Gross Carrying Amount	161,464	168,293
Accumulated Amortization	46,091	34,298
Net Carrying Amount	115,373	133,995
Above-market lease assets [Member]
Intangible assets:
Gross Carrying Amount	21,764	22,583
Accumulated Amortization	5,856	4,547
Net Carrying Amount	15,908	18,036
Below Market Ground Lease [Member]
Intangible assets:
Gross Carrying Amount	1,578	1,578
Accumulated Amortization	58	39
Net Carrying Amount	$ 1,520	$ 1,539