Share Tracking Awards Plans (Tables) - Share tracking award plans (STAP)

3 Months Ended

Mar. 31, 2017

Awards granted under the STAP

Schedule of assumptions to measure the fair value of outstanding STAP awards

	March 31, 2017		March 31, 2016
Expected volatility	36.3	%	37.4	%
Risk-free interest rate	1.4	%	0.9	%
Expected term of awards (in years)	2.4		3.2
Expected dividend yield	0.0	%	0.0	%

Summary of the activity and status of STAP awards

	Number of Awards		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in Years)	Aggregate Intrinsic Value (in millions)
Outstanding at January 1, 2017	5,113,838		$	91.51
Granted	—		—
Exercised	(463,183	)	75.15
Forfeited	(85,086	)	95.82
Outstanding at March 31, 2017	4,565,569		$	93.09	6.3	$	227.1
Exercisable at March 31, 2017	2,811,258		$	94.42	6.1	$	136.0
Unvested as of March 31, 2017	1,754,311		$	90.94	6.6	$	91.2

Schedule of share-based compensation benefit recognized in connection with STAP awards

Share-based compensation benefit recognized in connection with STAP awards is as follows (in millions):

	Three Months Ended March 31,
	2017			2016
Cost of product sales	$	(1.7	)	$	(12.0	)
Research and development	(5.8		)	(37.4		)
Selling, general and administrative	(17.1		)	(98.5		)
Share-based compensation benefit before taxes	$	(24.6	)	$	(147.9	)
Related income tax expense	9.0			52.4
Share-based compensation benefit, net of taxes	$	(15.6	)	$	(95.5	)