Shareholders' Equity (Tables)

12 Months Ended

Dec. 31, 2020

Shareholders' Equity

Summary of the components of accumulated other comprehensive income (loss), net of tax

Accumulated Other Comprehensive Income (Loss)

The following is a summary of the components of accumulated other comprehensive income (loss), net of tax (in millions):

					Accumulated
	Foreign		Pension		Other
	Currency		Liability		Comprehensive
	Translation		Adjustment		Income (Loss)
Balance at December 31, 2017	$	72.2		(45.2)		27.0
Other comprehensive income		(25.3)		11.9		(13.4)
Realized loss on reclassification		—		3.4		3.4
Balance at December 31, 2018		46.9		(29.9)		17.0
Other comprehensive income (loss)		(19.5)		(25.1)		(44.6)
Realized loss on reclassification		—		2.1		2.1
Balance at December 31, 2019		27.4	$	(52.9)	$	(25.5)
Other comprehensive income		22.0		2.3		24.3
Realized loss on reclassification		—		4.9		4.9
Balance at December 31, 2020	$	49.4	$	(45.7)	$	3.7

Schedule of the impact of stock-based compensation expense

The following presents the impact of stock-based compensation expense on our consolidated statements of income (in millions):

	2020		2019		2018
Stock options	$	1.8	$	2.7	$	4.2
Restricted stock awards		—		0.3		0.8
Restricted stock units		11.5		8.9		6.3
Total stock-based compensation	$	13.3	$	11.9	$	11.3

	2020		2019		2018
Costs of product revenue	$	2.0	$	1.8	$	1.7
Selling, general and administrative		9.3		8.3		7.9
Research and development		2.0		1.8		1.7
Total stock-based compensation	$	13.3	$	11.9	$	11.3

Schedule of stock option activity

Stock option activity is as follows:

				Weighted -
				Average
		Weighted-		Remaining	Aggregate
	Number of	Average Price		Contractual	Intrinsic Value
	Options	Per Share		Term (in Years)	(in millions) (a)
Outstanding at December 31, 2019	1,988,696	$	23.43	4.9	$	54.8
Granted	125,794		45.54
Exercised	(241,915)		20.29
Forfeited/Expired	(16,399)		20.98
Outstanding at December 31, 2020	1,856,176	$	25.32	4.2	$	53.5
Exercisable at December 31, 2020	1,546,061	$	22.14	3.9	$	49.5
Exercisable and expected to vest at December 31, 2020 (b)	1,818,104	$	24.95	4.2	$	53.1

(a) Represents the number of vested options at December 31, 2020, plus the number of unvested options at December 31, 2020 that are ultimately expected to vest based on our estimated forfeiture rate.

(b) The aggregate intrinsic value is calculated as the positive difference between the exercise price of the underlying options and the quoted price of our common stock on December 31, 2020.

Schedule of Unvested restricted stock unit activity

Unvested restricted stock unit activity is presented below:

		Weighted-
		Average Grant
	Shares	Date Fair
	Subject to	Value
	Restriction	Per Share
Outstanding at December 31, 2019	865,101	$	34.73
Granted	336,341		43.96
Vested	(336,728)		32.00
Forfeited	(59,662)		35.99
Outstanding at December 31, 2020	805,052	$	39.63