Real Estate and Lease Intangibles - Summary of Aggregate Amortization for Above and Below Market Ground And Retail Lease Intangibles (Details) $ in Thousands	Sep. 30, 2017 USD ($)
Finite-lived intangible assets, amortization expense, remainder of fiscal year 2017	$ (1,100)
Finite-lived intangible assets, amortization expense, year 2018	(4,392)
Finite-lived intangible assets, amortization expense, year 2019	(4,392)
Finite-lived intangible assets, amortization expense, year 2020	(4,392)
Finite-lived intangible assets, amortization expense, year 2021	(4,392)
Finite-lived intangible assets, amortization expense, year 2022	(4,436)
Ground Lease [Member]
Finite-lived intangible assets, amortization expense, remainder of fiscal year 2017	(1,116)
Finite-lived intangible assets, amortization expense, year 2018	(4,463)
Finite-lived intangible assets, amortization expense, year 2019	(4,463)
Finite-lived intangible assets, amortization expense, year 2020	(4,463)
Finite-lived intangible assets, amortization expense, year 2021	(4,463)
Finite-lived intangible assets, amortization expense, year 2022	(4,463)
Retail Lease [Member]
Finite lived intangible assets amortization income, reminder of fiscal year 2017	16
Finite-lived intangible assets; amortization income, year 2018	71
Finite-lived intangible assets; amortization income, year 2019	71
Finite-lived intangible assets; amortization income, year 2020	71
Finite-lived intangible assets; amortization income, year 2021	71
Finite-lived intangible assets; amortization income, year 2022	$ 27