Note 4 - Stock-based Compensation (Tables)

3 Months Ended

Mar. 31, 2024

Notes Tables

Share-Based Payment Arrangement, Cost by Plan [Table Text Block]

Millions, for the Three Months Ended March 31,	2024		2023
Stock-based compensation, before tax:
Stock options	$	4	$	4
Retention awards		17		18
ESPP		5		6
Total stock-based compensation, before tax	$	26	$	28
Excess income tax benefits from equity compensation plans	$	9	$	6

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

Weighted-Average Assumptions	2024			2023
Risk-free interest rate		4.2	%		3.9	%
Dividend yield		2.1	%		2.6	%
Expected life (years)		4.4			4.5
Volatility		28.7	%		29.3	%
Weighted-average grant-date fair value of options granted	$	61.75		$	48.31

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

	Options (thous.)		Weighted-Average Exercise Price			Weighted-Average Remaining Contractual Term (in yrs.)		Aggregate Intrinsic Value (millions)
Outstanding at January 1, 2024		2,072		$	180.56		5.9		$	135
Granted		305			248.82		N/A			N/A
Exercised		(102	)		127.77		N/A			N/A
Forfeited or expired		(5	)		223.49		N/A			N/A
Outstanding at March 31, 2024		2,270		$	192.01		6.3		$	123
Vested or expected to vest at March 31, 2024		2,251		$	191.67		6.3		$	123
Options exercisable at March 31, 2024		1,642		$	176.86		5.3		$	113

Cash Proceeds Received and Tax Benefit from Share-Based Payment Awards [Table Text Block]

Millions, for the Three Months Ended March 31,	2024			2023
Intrinsic value of stock options exercised	$	12		$	4
Cash received from option exercises		15			4
Treasury shares repurchased for employee payroll taxes		(4	)		(1	)
Income tax benefit realized from option exercises		3			1
Aggregate grant-date fair value of stock options vested		15			14

Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]

	Shares (thous.)			Weighted-Average Grant-Date Fair Value
Nonvested at January 1, 2024		996		$	207.76
Granted		211			248.77
Vested		(241	)		186.27
Forfeited		(15	)		218.56
Nonvested at March 31, 2024		951		$	222.13

Schedule of Nonvested Performance-Based Units Activity [Table Text Block]

	Shares (thous.)			Weighted-Average Grant-Date Fair Value
Nonvested at January 1, 2024		617		$	204.50
Granted		227			248.82
Vested		(119	)		204.59
Unearned		(70	)		204.45
Forfeited		(7	)		221.41
Nonvested at March 31, 2024		648		$	219.83