Summary Of Significant Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Accounting Policies [Abstract]
Total interest costs incurred	$ 30,241	$ 31,250
Interest capitalized	(2,836)	(2,457)
Interest expense	27,405	28,793
Cash paid for interest, net of amounts capitalized	30,315	31,669
Cash paid for income taxes	294	177
Dividends contributed to dividend reinvestment plan	$ (450)	$ (487)