Compensation Plans Outstanding Longer Term Incentive Awards (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Outstanding Long Term Incentive Awards [Line Items]
Target Shares Issuable as Long Term Incentive Awards	$ 55,203	$ 87,758
Maximum Shares Issuable as Long Term Incentive Awards	68,263	107,955
Unrecognized Compensation Cost - Long Term Incentives	$ 1,792,393	$ 949,095
Share-based Compensation Arrangement By Share-based Payment Award, Grants In Period, Weighted Average Grant Date Fair Value	$ 40,720	$ 25,260