Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2020

Share-based Payment Arrangement [Abstract]

The activity related to restricted stock units (“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, 2020			847		$	36.99
		Granted ^(a)	705		21.67
		Vested ^(b)	(397)		38.14
		Forfeited	(69)		33.51
	Outstanding and expected to vest at June 30, 2020 ^(c)			1,086		$	26.85		1.4		$	25
Performance-based and market-based RSUs
	Outstanding at January 1, 2020			1,061		$	38.89
		Granted ^(a)	552		21.06
		Vested ^(b)	(73)		36.64
		Forfeited	(414)		35.16
	Outstanding at June 30, 2020			1,126		$	31.67		2.0		$	26
	Outstanding and expected to vest at June 30, 2020 ^(c)			38		$	20.70		3.0		$	1

__________

^(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 six months ended June 30, 2019 was $34.90 and $34.87, respectively.

^(b)The total fair value of RSUs vested during June 30, 2020 and 2019 was $18 million and $13 million, respectively.

^(c)Aggregate unrecognized compensation expense related to time-based RSUs and performance-based and market-based RSUs amounted to $25 million and will be recognized over a weighted average vesting period of 1.5 years.