Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Summary of Stock Options Outstanding and Exercised Under Prior and Existing Stock Incentive Plans

The following is a summary of stock options outstanding and exercised under prior and existing stock incentive plans of the Company:

Year Ended December 31	Stock Options/Shares			Weighted- Average Exercise Price		Weighted-Average Remaining Contractual Term		Aggregate Intrinsic Value (in millions)
2021
Number outstanding at beginning of period		5,180,391		$	40.38
Exercised		(1,281,646	)		33.66
Cancelled(a)		(8,614	)		48.20
Number outstanding at end of period(b)		3,890,131		$	42.58		3.3	$	53
Exercisable at end of period		3,890,131		$	42.58		3.3	$	53
2020
Number outstanding at beginning of period		5,718,256		$	39.25
Exercised		(513,293	)		27.48
Cancelled(a)		(24,572	)		45.08
Number outstanding at end of period(b)		5,180,391		$	40.38		3.7	$	32
Exercisable at end of period		4,942,077		$	39.68		3.6	$	34
2019
Number outstanding at beginning of period		9,115,010		$	34.52
Exercised		(3,333,467	)		26.36
Cancelled(a)		(63,287	)		36.74
Number outstanding at end of period(b)		5,718,256		$	39.25		4.4	$	115
Exercisable at end of period		4,869,805		$	37.67		4.0	$	105

Note: The Company did not grant any stock option awards during 2021, 2020 and 2019.

(a) Options cancelled include both non-vested (i.e., forfeitures) and vested options.

(b) Outstanding options include stock-based awards that may be forfeited in future periods. The impact of the estimated forfeitures is reflected in compensation expense.

Summary of Certain Stock Option Activity

The following summarizes certain stock option activity of the Company:

Year Ended December 31 (Dollars in Millions)	2021		2020		2019
Fair value of options vested	$	3	$	7	$	10
Intrinsic value of options exercised		27		11		95
Cash received from options exercised		43		14		88
Tax benefit realized from options exercised		7		3		24

Stock Options Outstanding Additional Information

Additional information regarding stock options outstanding as of December 31, 2021, is as follows:

	Outstanding Options						Exercisable Options
Range of Exercise Prices	Shares		Weighted- Average Remaining Contractual Life (Years)		Weighted- Average Exercise Price		Shares		Weighted- Average Exercise Price
$25.01—$30.00		251,126		.1	$	28.63		251,126	$	28.63
$30.01—$35.00		446,538		1.1		33.98		446,538		33.98
$35.01—$40.00		1,051,053		4.1		39.49		1,051,053		39.49
$40.01—$45.00		1,269,994		2.7		42.43		1,269,994		42.43
$45.01—$50.00		—		—		—		—		—
$50.01—$55.01		871,420		5.1		54.96		871,420		54.96
		3,890,131		3.3	$	42.58		3,890,131	$	42.58

Summary of Company's Restricted Shares of Stock and Unit Awards

A summary of the status of the Company’s restricted shares of stock and unit awards is presented below:

	2021					2020					2019
Year Ended December 31	Shares			Weighted- Average Grant- Date Fair Value		Shares			Weighted- Average Grant- Date Fair Value		Shares			Weighted- Average Grant- Date Fair Value
Outstanding at beginning of period		6,343,313		$	51.38		6,606,833		$	48.99		6,719,298		$	48.17
Granted		4,512,995			52.54		3,552,923			53.90		3,519,474			50.45
Vested		(3,793,978	)		53.27		(3,534,770	)		49.28		(3,270,778	)		48.69
Cancelled		(249,577	)		52.83		(281,673	)		53.51		(361,161	)		50.55
Outstanding at end of period		6,812,753		$	51.04		6,343,313		$	51.38		6,606,833		$	48.99