Acquired Intangibles Assets and Liabilities - Amortization (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Acquired Intangible Assets and Liabilities
Amortization of acquired above and below-market leases, net	$ 200	$ 100	$ 479	$ 201
Amortization of all other identified intangible assets	4,600	$ 4,100	9,300	$ 8,600
Estimated amortization of acquired favorable and unfavorable leases Rental Expense
2017 (July - December)	108		108
2018	216		216
2019	216		216
2020	216		216
2021	216		216
Thereafter	1,039		1,039
Total	2,011		2,011
Finite Lived Intangible Assets Liabilities Amortization
Above Market Lease Net	2,011		2,011		$ 2,119
Estimated amortization of all other identified intangible assets
Net Carrying Value	119,384		119,384		129,754
Acquired favorable leases
Estimated amortization of all other identified intangible assets
Net Carrying Value	2,933		2,933		3,639
Acquired favorable leases
Estimated amortization of acquired favorable and unfavorable leases Rental Revenue
2017 (July - December)	493		493
2018	682		682
2019	479		479
2020	647		647
2021	46		46
Thereafter	33		33
Total	2,380		2,380
All other identified intangible assets
Estimated amortization of all other identified intangible assets
2017 (July - December)	8,916		8,916
2018	14,574		14,574
2019	11,965		11,965
2020	11,379		11,379
2021	10,137		10,137
Thereafter	48,159		48,159
Net Carrying Value	105,130		105,130
Solar Power Agreement
Estimated amortization of all other identified intangible assets
Net Carrying Value	$ 11,321		$ 11,321		$ 11,725