Intangible Assets (Intangibles - Future Amortization) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Future Amortization of Intangible Assets:
Weighted average remaining lease term	10 years
2019	$ 20,054
2020	15,374
2021	11,217
2022	7,646
2023	5,939
Thereafter	27,043
Finite-lived intangibles, net	87,273
Below Market Rents
Future Amortization of Intangible Liabilities:
2019	(11,645)
2020	(10,519)
2021	(8,753)
2022	(6,185)
2023	(4,844)
Thereafter	(13,272)
Finite-lived intangible liabilities, net	$ (55,218)
Weighted average remaining lease term	6 years
Above Market Ground Lease
Future Amortization of Intangible Liabilities:
2019	$ (46)
2020	(46)
2021	(46)
2022	(46)
2023	(46)
Thereafter	(1,488)
Finite-lived intangible liabilities, net	$ (1,718)
Weighted average remaining lease term	37 years
Below Market Ground Lease
Future Amortization of Intangible Assets:
2019	$ 276
2020	276
2021	276
2022	276
2023	276
Thereafter	16,412
Finite-lived intangible assets, net	$ 17,792	$ 18,067
Weighted average remaining lease term	65 years
Above Market Rents
Future Amortization of Intangible Assets:
2019	$ 5,308
2020	4,433
2021	3,374
2022	2,292
2023	1,710
Thereafter	3,336
Finite-lived intangible assets, net	$ 20,453	26,917
Weighted average remaining lease term	6 years
In Place Leases
Future Amortization of Intangible Assets:
2019	$ 26,161
2020	21,230
2021	16,366
2022	11,309
2023	8,843
Thereafter	22,055
Finite-lived intangible assets, net	$ 105,964	$ 139,548
Weighted average remaining lease term	6 years