Stock Option Plans and Share-Based Compensation Restricted Stock Awards and RSUs rollforward (Details) (USD $)					12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2013 Restricted Stock [Member]	Dec. 31, 2012 Restricted Stock [Member]	Dec. 31, 2011 Restricted Stock [Member]	Dec. 31, 2013 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2012 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2011 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2013 Range Two [Member]	Dec. 31, 2013 Range Three [Member]	Dec. 31, 2013 Range Four [Member]	Dec. 31, 2013 Range Five [Member]	Dec. 31, 2013 Range Six [Member]	Dec. 31, 2013 Range Seven [Member]	Dec. 31, 2013 Range Eight [Member]	Dec. 31, 2013 Range Nine [Member]	Dec. 31, 2013 Range Ten [Member]	Dec. 31, 2013 Range One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,143,000	4,470,000	4,693,000	4,740,000							384,000	347,000	358,000	364,000	382,000	434,000	330,000	136,000	76,000	332,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 15.82	$ 14.06	$ 13.36	$ 12.86							$ 10.65	$ 12.84	$ 13.86	$ 14.58	$ 16.79	$ 19.84	$ 22.52	$ 24.61	$ 29.16	$ 8.71
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	2,078,000										384,000	291,000	143,000	167,000	106,000	369,000	104,000	106,000	76,000	332,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 15.11										$ 10.65	$ 12.77	$ 13.94	$ 14.67	$ 16.51	$ 20.12	$ 21.50	$ 24.76	$ 29.16	$ 8.71
Number of shares [Roll Forward]
Beginning balance					58,000	68,000	77,000	389,000	287,000	308,000
Granted					55,000	67,000	68,000	190,000	274,000	145,000
Vested					(61,000)	(78,000)	(77,000)	(195,000)	(153,000)	(152,000)
Forfeited								22,000	(19,000)	(14,000)
Ending balance					52,000	58,000	68,000	362,000	389,000	287,000
Weighted-average grant date fair value per share [Roll Forward]
Beginning balance					$ 14.19	$ 14.71	$ 12.91	$ 14.09	$ 13.03	$ 12.98
Granted					$ 18.20	$ 14.19	$ 14.71	$ 19.87	$ 14.58	$ 14.39
Vested					$ 14.23	$ 14.64	$ 12.91	$ 14.31	$ 12.90	$ 14.26
Forfeited								$ 14.08	$ 14.55	$ 12.82
Ending balance					$ 18.43	$ 14.19	$ 14.71	$ 17.15	$ 14.09	$ 13.03
Vested in period, fair value					$ 1,126,670.00	$ 1,100,000.00	$ 1,100,000.00	$ 4,400,000	$ 2,300,000	$ 2,400,000
Compensation cost not yet recognized					$ 400,000			$ 5,500,000
Period for recognition					2 years			2 years 6 months