Stock-Based Compensation

3 Months Ended

Mar. 31, 2021

Share-based Payment Arrangement [Abstract]

The Company recorded stock-based compensation expense of $4 million and $(2) million ($3 million and $(1) million, net of tax) during the three months ended March 31, 2021 and 2020, respectively.

In June 2020, the Company granted market-based restricted stock units (“RSUs”) that vest based on absolute stock price attainment. The grant date fair value of this award is estimated using a Monte Carlo simulation model.

The weighted average assumptions used in the model are as follows:


Expected volatility of stock price						91%
Risk-free interest rate						0.18%
Valuation period						3 years
Dividend yield						—%

The activity related to RSUs consisted of (in thousands of shares):


			Number of Shares	Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Term (years)	Aggregate Intrinsic Value (in millions)
Time-based RSUs
	Outstanding at January 1, 2021		1,070	$	27.47
		Granted (a)	240	63.12
		Vested (b)	(375)	30.05
		Forfeited	(7)	25.35
	Outstanding and expected to vest at March 31, 2021 (c)		928	$	35.66	1.3	$	67
Performance-based and market-based RSUs
	Outstanding at January 1, 2021		988	$	32.41
		Granted (a)	236	62.27
		Vested (b)	—	—
		Forfeited	(272)	48.72
	Outstanding at March 31, 2021		952	$	35.14	2.0	$	69
	Outstanding and expected to vest at March 31, 2021 (c)		203	$	54.59	2.8	$	15

__________

(a)Reflects the maximum number of stock units assuming achievement of all performance-, market- and time-vesting criteria and does not include those for non-employee directors. The weighted-average fair value of time-based RSUs and performance-based and market-based RSUs granted during the three months ended March 31, 2020 was $21.67 and $21.09, respectively.

(b)The total fair value of RSUs vested during March 31, 2021 and 2020 was $11 million and $17 million, respectively.

(c)Aggregate unrecognized compensation expense related to time-based RSUs and performance-based and market-based RSUs amounted to $39 million and will be recognized over a weighted average vesting period of 1.6 years.