Fair Value Measures And Other Financial Instruments (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								1 Months Ended
	Mar. 31, 2012	Mar. 31, 2012 Fair Value, Inputs, Level 2 [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member]	Mar. 31, 2012 Fixed Rate Debt [Member]	Dec. 31, 2011 Fixed Rate Debt [Member]	Mar. 31, 2012 Variable Rate Debt [Member]	Dec. 31, 2011 Variable Rate Debt [Member]	Dec. 31, 2011 Three Interest Rate Swap [Member]	Jan. 31, 2012 Fourth Interest Rate Swap [Member]	Mar. 31, 2012 Term Loans Fully Drawn [Member]	Mar. 31, 2012 Atlanta Condominium Project [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2011 Atlanta Condominium Project [Member] Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notional amounts								$ 230,000	$ 70,000
Derivative, fixed interest rate								1.55%	1.50%	3.44%
LIBOR rate									one-month
Net liabilities		2,640	2,641
Accumulated comprehensive income (loss) to interest expense, future periods	2,997
Termination payment	2,537
Fair value of debt				890,803	885,455	103,564	137,495
Carrying value of debt				834,340	835,443	104,923	135,000
Fair value of contractual obligation											$ 4,883	$ 5,348