Unsecured Lines Of Credit Payable - Recognized Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Unsecured Debt [Abstract]
Line of Credit Facility, Periodic Payment, Interest	$ 3,272	$ 2,266	$ 196
Line of Credit Facility, Commitment Fee Amount	$ 1,220	$ 1,241	$ 1,267