Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended						9 Months Ended
	Oct. 31, 2024	Jul. 31, 2024	Apr. 30, 2024	Oct. 31, 2023	Jul. 31, 2023	Apr. 30, 2023	Oct. 31, 2024	Oct. 31, 2023	Nov. 30, 2024
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 2,474	$ 2,161	$ 1,855	$ 1,206	$ 897	$ 1,145	$ 1,855	$ 1,145
Common shares issued under stock plans	13	(38)	(62)	27	(31)	(21)
Stock-based compensation expense	184	170	151	179	195	160
Settlement of liability-classified restricted common shares			3		8	1	3	9
Net income	275	282	252	241	222	161	809	624
Other comprehensive (loss) income	(11)	14	(29)	(59)	2	(15)	(26)	(72)
Repurchase and retirement of common shares	(319)	(115)	(9)	(112)	(87)	(534)
Ending balance	$ 2,616	$ 2,474	$ 2,161	$ 1,482	$ 1,206	$ 897	$ 2,616	$ 1,482
Common Stock Repurchase Program
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock repurchased and retired (in shares)	1,190,000			543,000			1,694,000	4,000,000
Repurchased shares of its common stock on the open market, average repurchase price per share (in usd per share)	$ 269.30			$ 205.70			$ 262.15	$ 200.35
November 2022 Common Stock Repurchase Program
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Amount remained available for repurchase under repurchase plans	$ 4,300			$ 4,800			$ 4,300	$ 4,800
September 2016 Common Stock Repurchase Program
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares remained available for repurchase under repurchase plans (in shares)				0				0
Subsequent Event | November 2022 Common Stock Repurchase Program
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Amount remained available for repurchase under repurchase plans									$ 4,300
Subsequent Event | November 2024 Common Stock Repurchase Program
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock repurchase authorized amount									$ 5,000
Common stock and additional paid-in capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	215,000,000	215,000,000	214,000,000	214,000,000	214,000,000	215,000,000	214,000,000	215,000,000
Beginning balance	$ 4,009	$ 3,894	$ 3,802	$ 3,531	$ 3,368	$ 3,325	$ 3,802	$ 3,325
Common shares issued under stock plans (in shares)	1,000,000		1,000,000	1,000,000		2,000,000
Common shares issued under stock plans	$ 13	(38)	$ (62)	$ 27	(31)	$ (21)
Stock-based compensation expense	$ 184	170	151	$ 179	195	160
Settlement of liability-classified restricted common shares			$ 3		8	$ 1
Repurchase and retirement of common shares (in shares)	(1,000,000)			(1,000,000)		(3,000,000)
Repurchase and retirement of common shares	$ (106)	$ (17)		$ (59)	$ (9)	$ (97)
Ending balance (in shares)	215,000,000	215,000,000	215,000,000	214,000,000	214,000,000	214,000,000	215,000,000	214,000,000
Ending balance	$ 4,100	$ 4,009	$ 3,894	$ 3,678	$ 3,531	$ 3,368	$ 4,100	$ 3,678
Accumulated other comprehensive loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(249)	(263)	(234)	(198)	(200)	(185)	(234)	(185)
Other comprehensive (loss) income	(11)	14	(29)	(59)	2	(15)
Ending balance	(260)	(249)	(263)	(257)	(198)	(200)	(260)	(257)
Accumulated deficit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(1,286)	(1,470)	(1,713)	(2,127)	(2,271)	(1,995)	(1,713)	(1,995)
Net income	275	282	252	241	222	161
Repurchase and retirement of common shares	(213)	(98)	(9)	(53)	(78)	(437)
Ending balance	$ (1,224)	$ (1,286)	$ (1,470)	$ (1,939)	$ (2,127)	$ (2,271)	$ (1,224)	$ (1,939)