Other Assets And Deferred Charges, Net (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred Costs And Other Assets [Line Items]
Amortization expense of deferred charges	$ 5.4	$ 5.2	$ 5.6
Unsecured Revolving Credit Facility [Member]
Deferred Costs And Other Assets [Line Items]
Accumulated amortization of deferred lease origination costs	24.7
Accumulated amortization of deferred financing costs	$ 4.4