Acquired Intangibles Assets and Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Finite-lived intangible assets
Gross Carrying Value	$ 158,867	$ 158,867
Accumulated Amortization	(62,245)	(49,416)
Net Carrying Value	96,622	109,451
Acquired below market leases - as Lessor
Gross Carrying Value	809	809
Accumulated Amortization	(552)	(375)
Net Carrying Value	257	434
Acquired Intangible Liabilities
Acquired intangible liabilities	17,009	17,009
Accumulated Amortization	(4,701)	(3,755)
New Carrying Value	$ 12,308	$ 13,254
Minimum
Acquired below market leases - as Lessor
Useful Lives	3 years	3 years
Acquired above market leases - as Lessee
Useful Lives	11 years	11 years
Maximum
Acquired below market leases - as Lessor
Useful Lives	4 years	4 years
Acquired above market leases - as Lessee
Useful Lives	12 years	12 years
Customer Relationships
Finite-lived intangible assets
Gross Carrying Value	$ 95,705	$ 95,705
Accumulated Amortization	(26,474)	(20,512)
Net Carrying Value	$ 69,231	$ 75,193
Customer Relationships | Minimum
Finite-lived intangible assets
Useful Lives	1 year	1 year
Customer Relationships | Maximum
Finite-lived intangible assets
Useful Lives	12 years	12 years
In Place Leases
Finite-lived intangible assets
Gross Carrying Value	$ 32,066	$ 32,066
Accumulated Amortization	(16,581)	(12,987)
Net Carrying Value	$ 15,485	$ 19,079
In Place Leases | Minimum
Finite-lived intangible assets
Useful Lives	6 months	6 months
In Place Leases | Maximum
Finite-lived intangible assets
Useful Lives	10 years	10 years
Solar Power Agreement
Finite-lived intangible assets
Useful Lives	17 years	17 years
Gross Carrying Value	$ 13,747	$ 13,747
Accumulated Amortization	(3,437)	(2,830)
Net Carrying Value	10,310	10,917
Acquired Intangible Liabilities
Acquired intangible liabilities	13,747	13,747
Accumulated Amortization	(3,437)	(2,830)
New Carrying Value	$ 10,310	$ 10,917
Platform Intangible
Finite-lived intangible assets
Useful Lives	3 years	3 years
Gross Carrying Value	$ 9,600	$ 9,600
Accumulated Amortization	(9,600)	(8,133)
Net Carrying Value		1,467
Acquired favorable leases
Finite-lived intangible assets
Gross Carrying Value	4,649	4,649
Accumulated Amortization	(3,053)	(2,328)
Net Carrying Value	$ 1,596	$ 2,321
Acquired favorable leases | Minimum
Finite-lived intangible assets
Useful Lives	6 months	6 months
Acquired favorable leases | Maximum
Finite-lived intangible assets
Useful Lives	8 years	8 years
Tradenames
Finite-lived intangible assets
Useful Lives	3 years	3 years
Gross Carrying Value	$ 3,100	$ 3,100
Accumulated Amortization	(3,100)	(2,626)
Net Carrying Value		474
Above Market Leases
Acquired Intangible Liabilities
Acquired intangible liabilities	2,453	2,453
Accumulated Amortization	(712)	(550)
New Carrying Value	$ 1,741	$ 1,903