Capital Stock (Tables)

6 Months Ended

Jun. 30, 2023

Banking Regulation, Total Capital [Abstract]

Summary of Cash Dividend Activity

A summary of our cash dividend activity for the six months ended June 30, 2023 and 2022 is as follows: 

Declaration Date	Record Date	Payment Date	Cash Dividend per Share	Total
Six Months Ended June 30, 2023
January 24, 2023	March 10, 2023	March 24, 2023	$1.48	$	351
April 18, 2023	June 9, 2023	June 23, 2023	$1.48	$	350
Six Months Ended June 30, 2022
January 25, 2022	March 10, 2022	March 25, 2022	$1.28	$	309
April 19, 2022	June 10, 2022	June 24, 2022	$1.28	$	309

Summary of Share Repurchases

A summary of common stock repurchases for the six months ended June 30, 2023 and 2022 is as follows:

	Six Months Ended June 30
	2023		2022
Shares repurchased	2.7		2.5
Average price per share	$	466.62	$	471.72
Aggregate cost	$	1,268	$	1,169
Authorization remaining at the end of the period	$	5,608	$	3,022

Summary of Stock Option Activity

A summary of stock option activity for the six months ended June 30, 2023 is as follows:

	Number of Shares	Weighted- Average Option Price per Share		Weighted- Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Outstanding at January 1, 2023	2.8	$	293.28
Granted	0.6	469.05
Exercised	(0.2)	268.35
Forfeited or expired	—	391.44
Outstanding at June 30, 2023	3.2	323.85		6.51	$	402
Exercisable at June 30, 2023	2.1	265.51		5.31	$	376

Summary of Nonvested Restricted Stock Activity Including Restricted Stock Units

A summary of the status of nonvested restricted stock activity, including restricted stock units and performance units, for the six months ended June 30, 2023 is as follows:

	Restricted Stock Shares and Units	Weighted- Average Grant Date Fair Value per Share
Nonvested at January 1, 2023	1.2	$	357.21
Granted	0.6	469.60
Vested	(0.6)	301.18
Forfeited	—	405.25
Nonvested at June 30, 2023	1.2	422.67

Summary of Weighted-Average Assumptions Used to Estimate the Fair Value of Options Granted During the Periods

The following weighted-average assumptions were used to estimate the fair values of options granted during the six months ended June 30, 2023 and 2022:

	Six Months Ended June 30
	2023		2022
Risk-free interest rate	3.95	%	1.97	%
Volatility factor	29.00	%	29.00	%
Quarterly dividend yield	0.316	%	0.282	%
Weighted-average expected life (years)	4.40		5.10

Schedule of Weighted-Average Fair Values Determined for the Periods

The following weighted-average fair values per option or share were determined for the six months ended June 30, 2023 and 2022: 

	Six Months Ended June 30
	2023		2022
Options granted during the period	$	127.13	$	116.80
Restricted stock awards granted during the period	469.60		452.78