Per Share Data (Calculation Of Basic And Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Number of common share equivalent securities excluded from the diluted earnings per share calculation	2,200,000	3,500,000	2,200,000	2,500,000
Income from continuing operations attributable to common shareholders	$ 48,956	$ 19,083	$ 79,941	$ 73,041
Amount allocated to participating securities	(696)	(210)	(1,335)	(1,099)
Income from continuing operations attributable to common shareholders, net of amount allocated to participating securities	48,260	18,873	78,606	71,942
Income from discontinued operations, including gain on sale, attributable to common shareholders	23,216	2,680	55,707	37,480
Net income attributable to common shareholders, as adjusted	71,476	21,553	134,313	109,422
Income from continuing operations attributable to common shareholders, as adjusted - per share	$ 0.55	$ 0.23	$ 0.90	$ 0.88
Income from discontinued operations, including gain on sale, attributable to common shareholders	$ 0.27	$ 0.03	$ 0.64	$ 0.46
Net income attributable to common shareholders, as adjusted - per share	$ 0.82	$ 0.26	$ 1.54	$ 1.34
Weighted average number of common shares outstanding - basic	87,191,000	83,223,000	86,949,000	81,554,000
Income allocated to common units	315	0	645	572
Income from continuing operations attributable to common shareholders, as adjusted	48,575	18,873	79,251	72,514
Income from discontinued operations allocated to common units	0	0	0	784
Net income attributable to common shareholders, as adjusted	$ 71,791	$ 21,553	$ 134,958	$ 110,778
Income from continuing operations attributable to common shareholders, as adjusted - per share	$ 0.55	$ 0.23	$ 0.90	$ 0.87
Income from discontinued operations, including gain on sale, attributable to common shareholders - per share	$ 0.26	$ 0.03	$ 0.63	$ 0.46
Net income attributable to common shareholders, as adjusted - per share	$ 0.81	$ 0.26	$ 1.53	$ 1.33
Common share options and share awards granted	467,000	623,000	519,000	652,000
Common units	814,000	0	815,000	1,127,000
Weighted average number of common shares outstanding - diluted	88,472,000	83,846,000	88,283,000	83,333,000

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method and incremental common shares attributable to participating nonvested shares with non-forfeitable dividend rights using the two class method.

No definition available.