Options and Awards Valuation Assumptions (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Fair Value Assumptions and Methodology
Options Granted	103	109	383	397
Weighted Average Risk-Free Rate	1.88%	1.29%	1.94%	1.37%
Expected Life	6 years 1 month 25 days	6 years 2 months 35 days	6 years 2 months	6 years 2 months 35 days
Weighted Average Volatility	35.40%	35.90%	35.70%	38.30%
Weighted Average Dividend Yield	0.84%	0.84%	0.84%	0.80%