Earnings Per Share (Details) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]
Average common shares outstanding - basic (in shares)	124,256	123,635	124,011	123,468
Effect of dilutive securities - share-based compensation (in shares)	794	966	835	915
Average common shares - diluted (in shares)	125,050	124,601	124,846	124,383
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive shares	1,092	1,031	1,092	1,065
Share appreciation rights [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive shares	1,050	978	1,050	1,012
Employee and director share options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total potentially dilutive shares	42	53	42	53