Intangibles Schedule of Intangible Asset Amortization Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Finite-Lived Intangible Assets, Amortization Expense [Line Items]
Amortization of Intangible Assets	$ 14,922,000	$ 12,694,000	$ 8,815,000
Ground Lease [Member]
Schedule of Finite-Lived Intangible Assets, Amortization Expense [Line Items]
Amortization of Intangible Assets	809,000	600,000	0
Leases, Acquired-in-Place [Member]
Schedule of Finite-Lived Intangible Assets, Amortization Expense [Line Items]
Amortization of Intangible Assets	13,812,000	11,559,000	8,299,000
Franchise Rights [Member]
Schedule of Finite-Lived Intangible Assets, Amortization Expense [Line Items]
Amortization of Intangible Assets	$ 301,000	$ 535,000	$ 516,000