Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation Expense

Stock based compensation expense for the years ended December 31, 2018, 2017 and 2016 was as follows:

	2018		2017		2016
Stock based compensation	$	133.8	$	83.1	$	78.8
Tax benefit recognized in net earnings	28.1		29.1		27.6

Weighted-Average Assumptions of Stock-Based Compensation

The weighted-average fair value of options granted in 2018, 2017 and 2016 were calculated using the following weighted-average assumptions:

	2018	2017	2016
Weighted-average fair value ($)	57.75	40.87	34.57
Risk-free interest rate (%)	2.65	2.03	1.44
Average expected option life (years)	5.32	5.26	5.20
Expected volatility (%)	18.05	18.74	21.35
Expected dividend yield (%)	0.59	0.67	0.70

Share-Based Compensation Activity

The following table summarizes the Company’s activities with respect to its share-based compensation plans for the years ended December 31, 2018 and 2017:

	Number of shares		Weighted-average exercise price per share		Weighted-average contractual term	Aggregate intrinsic value
Outstanding at January 1, 2017	3.420		$	121.31
Granted	0.609		210.56
Exercised	(0.645	)	95.14
Canceled	(0.188	)	170.75
Outstanding at December 31, 2017	3.196		140.68		6.09	$	368.6
Granted	0.723		279.10
Exercised	(0.650	)	90.43
Canceled	(0.064	)	211.57
Outstanding at December 31, 2018	3.205		180.69		6.58	$	284.0
Exercisable at December 31, 2018	1.627		$	129.39	4.71	$	223.1

Schedule of Stock-Based Compensation by Exercise Price Range

The following table summarizes information for stock options outstanding at December 31, 2018:

	Outstanding options				Exercisable options
Exercise price	Number	Average exercise price		Average remaining life (years)	Number	Average exercise price
$41.78 - $60.80	0.121	$	48.49	0.8	0.121	$	48.49
$60.80 - $91.21	0.149	72.06		2.2	0.149	72.06
$91.21 - $121.61	0.359	107.23		3.5	0.359	107.23
$121.61 - $152.01	0.436	136.54		5.1	0.436	136.54
$152.01 - $182.41	0.783	169.01		6.8	0.498	167.63
$182.41 - $212.81	0.534	201.40		8.1	0.055	186.22
$212.81 - $243.22	0.097	230.02		8.5	0.008	227.94
$243.22 - $273.62	0.027	258.82		9.0	0.001	260.01
$273.62 - $304.02	0.699	279.24		9.2	—	—
$41.78 - 304.02	3.205	$	180.69	6.6	1.627	$	129.39

Schedule of Nonvested Restricted Stock Awards Activity

A summary of the Company’s nonvested shares activity for 2018 and 2017 is as follows:

	Number of shares		Weighted-average grant date fair value
Nonvested at December 31, 2016	0.953		$	164.62
Granted	0.410		205.88
Vested	(0.387	)	155.95
Forfeited	(0.117	)	173.53
Nonvested at December 31, 2017	0.859		$	187.01
Granted	0.410		278.29
Vested	(0.492	)	204.24
Forfeited	(0.038	)	191.51
Nonvested at December 31, 2018	0.739		$	225.93