Note 12. Stock-Based Compensation Incentive Equity Awards Activity - Summary of Stock Options Valuation Assumptions (Details) - Options - $ / shares		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value Assumptions
Weighted average grant date fair value		$ 8.61	$ 10.81	$ 17.66
Weighted average expected volatility (a)	[1]	30.70%	31.70%	36.10%
Weighted average expected term (years) (b)	[2]	6 years 3 months	6 years 3 months	6 years 3 months
Weighted average risk-free interest rate (c)	[3]	2.00%	1.30%	1.60%
Weighted average dividend yield		1.20%	0.10%	0.00%

[1] (a)Expected volatility was based on historical volatilities of the Company and select comparable companies.

[2] (b)The expected term of the options granted represents the period of time that options are expected to be outstanding and is based on the simplified method.

[3] (c)The risk-free interest rate was based on the U.S. Treasury yield curve in effect at the time of the grant, which corresponds to the expected term of the options.