Related-party transactions and party in interest - Schedule of Related Party Transactions (Details) - EBP, Employer, Common Stock - EBP 004 - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
EBP, Related Party and Party-in-Interest Transactions [Line Items]
Purchases	$ 32,994,000	$ 26,842,000
Sales	31,385,000	76,847,000
Cash dividends received	12,454,000	13,302,000
Realized gains	754,000	21,943,000
Unrealized gains	$ 30,148,000	$ 114,111,000

Amount of increase (decrease) in net asset available for benefit from realized gain (loss) on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of increase in net asset available for benefit from dividend income on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Cost of investment, excluding plan interest in master trust, acquired by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Amount of selling price for investment, excluding plan interest in master trust, sold by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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