Stock Option and Incentive Plan Schedule of Stock Options Status (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning Outstanding, Shares	547,129	553,312	558,823
Beginning Oustanding, Weighted Average Exercise Price	$ 96.38	$ 97.21	$ 100.43
Exercised, Shares	0	(11,447)	21,459
Exercised, Weighted Averge Exercise Price	$ 0.00	$ 92.50	$ 97.04
Canceled, Shares			(2,444)
Canceled, Weighted Average Exercise Price			$ 103.57
Special dividend adjustment (shares)		5,264	18,392
Special dividend adjustment weighted average exercise price		$ 96.38	$ 97.22
Ending Outstanding, Shares	547,129	547,129	553,312
Ending Oustanding, Weighted Average Exercise Pric	$ 96.38	$ 96.38	$ 97.21