Share repurchases (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		1 Months Ended	3 Months Ended
	May 08, 2025	May 12, 2025	Mar. 31, 2025	Mar. 31, 2024	Sep. 05, 2024
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock (in shares)			3,660	2,119
Treasury Stock, Value, Acquired, Cost Method			$ 550,222	$ 240,117
Treasury Stock Acquired, Average Cost Per Share			$ 148.94	$ 112.76
Stock Repurchase Program, Authorized Amount					$ 2,000,000
Open Market Purchases
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock (in shares)			3,457	2,119
Treasury Stock, Value, Acquired, Cost Method			$ 518,221	$ 240,117
Treasury Stock Acquired, Average Cost Per Share			$ 148.53	$ 112.76
Berkshire Repurchases
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock (in shares)			203	0
Treasury Stock, Value, Acquired, Cost Method			$ 32,001	$ 0
Treasury Stock Acquired, Average Cost Per Share			$ 156.01	$ 0
Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock (in shares)		1,730
Treasury Stock, Value, Acquired, Cost Method		$ 259,152
Treasury Stock Acquired, Average Cost Per Share		$ 148.34
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 1,132,566
Subsequent Event | Berkshire
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock (in shares)	1,146
Treasury Stock, Value, Acquired, Cost Method	$ 170,263
Treasury Stock Acquired, Average Cost Per Share	$ 147.11