Summary Of Significant Accounting Policies Summary Of Significant Accounting Policies (Earnings per share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator:
Net income	$ 41,880	$ 36,417	$ 116,699	$ 118,179
Less: earnings distributed to participating securities	(130)	0	(263)	0
Less: undistributed earnings allocated to participating securities	(159)	0	(546)	0
Numerator for basic earnings per share	41,591	36,417	115,890	118,179
Add back: undistributed Earnings Allocated to Participating Securities	159	0	546	0
Less: undistributed earnings reallocated to participating securities	(157)	0	(540)	0
Numerator for diluted earnings per share	$ 41,593	$ 36,417	$ 115,896	$ 118,179
Denominator:
Basic shares outstanding	376,072	385,389	377,410	384,813
Effect of dilutive securities	3,592	5,791	3,703	5,943
Diluted shares outstanding	379,664	391,180	381,113	390,756
Earnings Per Share [Abstract]
Earnings Per Share, Basic	$ 0.11	$ 0.09	$ 0.31	$ 0.31
Earnings Per Share, Diluted	$ 0.11	$ 0.09	$ 0.30	$ 0.30