Components of Rental Income and Expense (Components Of Rental Expenses) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Component of Operating Other Cost and Expense [Line Items]
Repairs and maintenance	$ 46,600	$ 41,550	$ 41,873
Utilities	19,219	19,201	18,817
Management fees and costs	16,250	15,167	14,989
Payroll	9,237	8,691	8,067
Bad debt expense	442	2,173	2,643
Ground rent	1,916	2,189	2,047
Insurance	6,811	6,267	5,254
Marketing	8,664	7,321	6,868
Other operating	9,556	10,057	8,806
Rental expenses	$ 118,695	$ 112,616	$ 109,364