Favorable and Unfavorable Acquired Lease Contracts, net - Future Amortization (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 14.6	$ 15.1	$ 15.2
Weighted Average Life (Years)	11 years 6 months
Expected future amortization of lease contract rights
2017	$ 7.2
2018	5.3
2019	5.2
2020	5.2
2021	5.2
2022 and Thereafter	33.2
Acquired Intangible Assets, Net	61.3	75.9
Expected future (accretion) of lease contract rights
2017	(9.0)
2018	(7.3)
2019	(4.8)
2020	(3.7)
2021	(2.7)
2022 and Thereafter	(12.7)
Total acquired fair value of lease contracts, net	(40.2)	(50.3)
Expected future amortization (accretion) of lease contract rights
2017	2.6
2018	3.3
2019	1.2
2020	0.6
2021	0.3
2022 and Thereafter	2.2
Off Market Lease Unfavorable, Net	(10.2)
Favorable
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 1.8	$ 0.9
Weighted Average Life (Years)	11 years 10 months 24 days	11 years 1 month 6 days	10 years 9 months 18 days
Expected future amortization of lease contract rights
2017	$ 6.4
2018	4.0
2019	3.6
2020	3.1
2021	2.4
2022 and Thereafter	10.5
Acquired Intangible Assets, Net	$ 30.0	$ 38.1
Unfavorable
Finite-Lived Intangible Assets [Line Items]
Weighted Average Life (Years)	10 years 6 months	10 years 1 month 6 days	9 years 9 months 18 days