Employee Benefits And Stock-Based Compensation Employee Benefits And Stock-Based Compensation (Share-based Compensation by award type) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation	$ 43,977	$ 36,649	$ 33,362
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	(2,751)	(2,993)	(2,837)
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation	32,304	29,123	28,874
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation	10,232	5,033	1,933
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation	4,192	5,307	4,436
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation	$ 0	$ 179	$ 956