Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of Additional Stock-Based Compensation Disclosures

Stock-based compensation expense and the related tax benefits were as follows:

	2017		2016		2015
Stock-based compensation expense	$	281.3	$	255.3	$	217.8
Tax benefit	70.5		89.4		76.2

Share-based Compensation Awards, Fair Value Assumptions Used

The weighted-average fair values of the SVA units granted during the years ended December 31, 2017, 2016, and 2015 were $66.25, $48.68, and $54.81, respectively, determined using the following assumptions:

(Percents)	2017		2016		2015
Expected dividend yield	2.50	%	2.00	%	2.50	%
Risk-free interest rate	1.38		0.92		0.79
Volatility	22.91		21.68		20.37