Stock Compensation Plans (Tables)

3 Months Ended

Mar. 31, 2020

Share-based Payment Arrangement [Abstract]

Schedule of Stock-based Compensation Expense

Stock-based compensation expense for the following periods were:

In millions	Three months ended March 31
	2020			2019
Restricted stock units	$	19		$	20
Stock options	4			2
Employee stock purchase plan	2			1
Stock-based compensation expense	25			23
Tax benefit	(3		)	(3		)
Stock-based compensation expense (net of tax)	$	22		$	20

Schedule of Valuation Assumptions Used To Estimate Fair Value of Stock Options

he weighted average fair value of the option grants was $7.85 based on using a Monte-Carlo simulation model and will be recognized over the requisite service period. These option grants have a seven year contractual term that vest at the end of 36 months. For the three months ended March 31, 2019, the weighted average fair value of option grants was $8.07 with a seven year contractual term that vest ratably over four years. The table below details the assumptions used in determining the fair value of the option grants.

	Three months ended March 31
	2020			2019
Dividend yield	$	—		$	—
Risk-free interest rate	1.46		%	2.50		%
Expected volatility	33.38		%	34.79		%
Expected holding period (years)	3.7			3.9

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