Long-term debt - Narrative (Details) - Line of Credit	Jan. 25, 2024 USD ($)	Dec. 31, 2023 USD ($)
Revolving Credit Facility \| Amended And Restated Competitive Advance And Revolving Credit Agreement
Debt Instrument [Line Items]
Unused borrowing capacity		$ 1,490,000,000
Maximum borrowing capacity		1,510,000,000
Outstanding borrowing		$ 0
Revolving Credit Facility \| Amended And Restated Competitive Advance And Revolving Credit Agreement \| Subsequent Event
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 750,000,000
Debt instrument, term	5 years
Leverage ratio, step-up	0.5
Restricted cash amount requirement	$ 600,000,000
Debt instrument covenant consolidated leverage ratio	4.50
Letter of Credit \| Amended And Restated Competitive Advance And Revolving Credit Agreement \| Subsequent Event
Debt Instrument [Line Items]
Springing maturity, term	91 days
Springing maturity threshold	$ 300,000,000
Bridge Loan \| Subsequent Event
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 50,000,000

Debt Instrument, Covenant, Leverage Ratio, Maximum

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Debt Instrument, Covenant, Springing Maturity Threshold

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Debt Instrument, Covenant, Unrestricted Cash Requirement

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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