Share Based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Valuation And Expense Information [Abstract]
Total Cost Of Share Based Payment Plans	$ 6,137	$ 8,640	$ 13,957
Amounts capitalized in fixed costs	2,009	3,173	4,190
Amounts charged against income, before income tax benefit	4,128	5,467	9,767
Amount of related income tax benefit recognized in income	$ 1,645	$ 2,285	$ 4,083