Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2019

Stock-Based Compensation

Schedule of stock option activity

				Weighted
				Average	Aggregate
		Weighted		Remaining	Intrinsic
		Average		Contractual	Value
	Options	Exercise Price		Term (in years)	(in millions)
Options outstanding at January 1, 2019	35,550,668	$	59.77	6.81	$	798.6
Options granted	40,000		78.12
Options exercised	(1,269,121)		37.30
Options forfeited	(40,440)		75.17
Options outstanding at March 31, 2019	34,281,107	$	60.60	6.67	$	1,160.0
Vested and non-vested options expected to vest at March 31, 2019	32,308,769	$	59.92	6.59	$	1,115.4
Exercisable options at March 31, 2019	15,053,947	$	46.98	5.17	$	714.4

Summary of status of non-vested options and changes during the year

		Weighted
		Average
		Fair Value at
	Options	Grant Date
Non-vested options at January 1, 2019	19,289,500	$	9.73
Options granted	40,000		10.48
Options vested	(61,900)		8.27
Options forfeited	(40,440)		9.74
Non-vested options at March 31, 2019	19,227,160	$	9.74

Summary of activity in the option plans

	Three Months Ended
	March 31,
	2019		2018
Total intrinsic value of stock options exercised	$	70.0	$	34.3
Total fair value of stock options vested		0.5		0.5

Schedule of restricted share activity

				Weighted Average
				Remaining
	Restricted	Fair Value at		Amortization
	Shares	Grant Date		Term (in years)
Restricted shares outstanding at January 1, 2019	14,873	$	87.89	0.39
Restricted shares granted	—		—
Restricted shares outstanding at March 31, 2019	14,873	$	87.89	0.14