Deferred Charges and Other Assets, net - Schedule of estimated amortization of allocated values of above and below-market leases for the next five years and thereafter (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Above Market
2018	$ 13,165
2019	11,115
2020	8,418
2021	6,866
2022	5,136
Thereafter	15,183
Allocated value net	59,883
Above Market
Above Market
2018	11,109
2019	9,265
2020	8,088
2021	6,944
2022	5,370
Thereafter	63,054
Allocated value net	103,830	$ 124,346
Below Market
Below Market
2017	11,657
2018	10,400
2019	8,016
2020	6,286
2021	5,201
Thereafter	23,524
Allocated value, net	$ 65,084	$ 86,313