Lease Intangibles - Scheduled Amortization (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Acquired Lease Intangibles [Abstract]
Amortizable Intangible Assets, Net Carrying Amount	$ (125,050)	$ (127,571)
In-place lease intangible assets
Acquired Lease Intangibles [Abstract]
2018 (Remainder), Net Increase In Lease Revenues	6,219
2019, Net Increase In Lease Revenues	9,596
2020, Net Increase In Lease Revenues	8,830
2021, Net Increase In Lease Revenues	7,650
2022, Net Increase In Lease Revenues	7,353
Thereafter, Net Increase In Lease Revenues	57,431
Net Increase In Lease Revenues, Total	97,079
2018 (Remainder), Increase to Amortization	(19,544)
2019, Increase to Amortization	(23,316)
2020, Increase to Amortization	(17,389)
2021, Increase to Amortization	(12,760)
2022, Increase to Amortization	(8,949)
Thereafter, Increase to Amortization	(36,520)
Amortizable Intangible Assets, Net Carrying Amount	(118,478)	$ (121,072)
2018 (Remainder), Reduction of Rent Expense	44
2019, Reduction of Rent Expense	58
2020, Reduction of Rent Expense	58
2021, Reduction of Rent Expense	58
2022, Reduction of Rent Expense	58
Thereafter, Reduction of Rent Expense	346
Reduction of Rent Expense, Total	622
2018 (Remainder), Net Income (Expense)	(13,281)
2019, Net Income (Expense)	(13,662)
2020, Net Income (Expense)	(8,501)
2021, Net Income (Expense)	(5,052)
2022, Net Income (Expense)	(1,538)
Thereafter, Net Income (Expense)	21,257
Total, Net Income (Expense)	$ (20,777)