Stock Plans (Tables)

6 Months Ended

Jun. 30, 2020

Share-based Payment Arrangement [Abstract]

Disclosure of share-based compensation arrangements by payment award

During the six months ended June 30, 2020 and 2019, shares granted to eligible employees and the weighted-average grant date fair value per share related to RSU awards were as follows:

	Number of Shares Granted	Weighted-Average Grant Date Fair Value Per RSU Award Granted
2020	1,692,650	$ 85.91
2019	1,643,780		$ 77.18

Compensation expense related to RSU awards was as follows:

	Compensation Expense Related to RSU Awards
(in millions)	For the Six Months Ended June 30,		For the Three Months Ended June 30,
2020	$ 68		$ 29
2019		$ 64		$ 28

During the six months ended June 30, 2020 and 2019, shares granted to eligible employees and the grant date fair value per share related to PSU awards were as follows:

	Number of Shares Granted	PSU Grant Date Fair Value Subject to Other Performance Factors Per Share		PSU Grant Date Fair Value Subject to TSR Performance Factor Per Share
2020	671,220	$ 86.04		$ 80.36
2019	625,200		$ 77.20		$ 83.59

Compensation expense related to PSU awards was as follows:

	Compensation Expense Related to PSU Awards
(in millions)	For the Six Months Ended June 30,		For the Three Months Ended June 30,
2020	$ 32		$ 9
2019		$ 33	$ 15

Schedule of assumptions used to determine the grant date fair value of the PSU awards subject to the TSR performance factor

The following assumptions were used to determine the grant date fair value of the PSU awards subject to the TSR performance factor:

	2020		2019
Risk-free interest rate (a)	1.4	%	2.4	%
Expected volatility (b)	23.5	%	21.4	%

^(a) Based on the U.S. Treasury yield curve.

^(b) Determined using the observed historical volatility.