Summary of Quarterly Results (Tables)

12 Months Ended

Dec. 31, 2011

Quarterly Financial Data Tables [Abstract]

Schedule Of Quarterly Financial Information Table Text Block

						Net Income
						Attributable		Net Income Per
						to Common		Common Share (2)
	(Amounts in thousands, except per share amounts)			Revenues		Shareholders (1)		Basic		Diluted
		2011
			December 31	$	741,815	$	69,508	$	0.38	$	0.37
			September 30		727,343		41,135		0.22		0.22
			June 30		719,624		91,913		0.50		0.49
			March 31		726,883		399,215		2.17		2.12
		2010
			December 31	$	702,836	$	243,414	$	1.33	$	1.31
			September 30		687,125		95,192		0.52		0.52
			June 30		674,192		57,840		0.32		0.31
			March 31		676,528		200,285		1.10		1.09
_______________________________
	(1)		Fluctuations among quarters resulted primarily from non-cash impairment losses, mark-to-market of derivative instruments, net gains on sale of real estate and from seasonality of business operations.
	(2)		The total for the year may differ from the sum of the quarters as a result of weighting.