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Capital stock (Details) - USD ($)									3 Months Ended							9 Months Ended		12 Months Ended
	Sep. 11, 2025	Jun. 18, 2025	Mar. 11, 2025	Feb. 06, 2025	Sep. 11, 2024	Jun. 10, 2024	Mar. 11, 2024	Feb. 08, 2024	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Equity, Class of Treasury Stock [Line Items]
Stock repurchase authorized amount									$ 2,750,000,000							$ 2,750,000,000
Shares repurchased and retired (in shares)																3,919,239	4,720,308
Common stock shares repurchased price per share (in usd per share)																$ 46.68	$ 35.50
Expenses related to stock purchase																$ 978,000	$ 294,000
Stock repurchase program, remaining authorized repurchase amount									$ 464,061,000							$ 464,061,000
Increase in quarterly cash dividend (in percentage)				11.00%				11.00%
Dividend declared (in usd per share)									$ 0.17	$ 0.17	$ 0.17	$ 0.1525	$ 0.1525	$ 0.1525	$ 0.1375	$ 0.51	$ 0.4575		$ 0.61	$ 0.55
Dividends common stock	$ 29,293,000	$ 29,624,000	$ 29,784,000		$ 26,939,000	$ 27,337,000	$ 27,492,000		$ 29,293,000			$ 26,939,000				$ 88,701,000	$ 81,768,000
Forecast
Equity, Class of Treasury Stock [Line Items]
Dividend declared (in usd per share)																		$ 0.68
Share Repurchase Open Market
Equity, Class of Treasury Stock [Line Items]
Aggregate amount of common stock shares repurchased																182,944,000	$ 167,562,000
Q1 2025
Equity, Class of Treasury Stock [Line Items]
Stock repurchase authorized amount									$ 500,000							$ 500,000

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