Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2019

Share-based Payment Arrangement [Abstract]

Schedule of stock-based compensation expense and tax benefits

The following table reflects activity related to our stock-based compensation arrangements (in millions):

	Year Ended December 31,
	2019		2018		2017
Stock-based compensation expense:
Restricted stock	$	64	$	63	$	58
Performance awards	23		22		19
Stock options and other awards	2		1		—
Total stock-based compensation expense	$	89	$	86	$	77
Tax benefit recognized on stock-based compensation expense	$	19	$	18	$	27
Tax benefit realized for tax deductions resulting from exercises and vestings	17		32		44
Effect of tax deductions in excess of recognized stock-based compensation expense	7		20		24

Summary of restricted stock awards

A summary of the status of our restricted stock awards is presented in the following table.

	Number of Shares		Weighted- Average Grant-Date Fair Value Per Share
Nonvested shares as of January 1, 2019	1,176,578		$	80.70
Granted	677,482		98.75
Vested	(757,217	)	78.54
Forfeited	(4,989	)	83.18
Nonvested shares as of December 31, 2019	1,091,854		93.38

The following table reflects activity related to our restricted stock:

	Year Ended December 31,
	2019		2018		2017
Weighted-average grant-date fair value per share of restricted stock granted	$	98.75	$	92.12	$	79.32
Fair value of restricted stock vested (in millions)	74		80		71