Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Jul. 31, 2022	Apr. 30, 2022	Jan. 31, 2022	Jul. 31, 2021	Apr. 30, 2021	Jan. 31, 2021
Statement of Stockholders' Equity [Abstract]
Purchase of treasury shares (in shares)	448,889,000	469,604,000	147,784,000	76,724,000	127,297,000	27,347,000
Dividends declared (in dollars per share)	$ 0.51	$ 0.51	$ 0.51	$ 0.39	$ 0.39	$ 0.39