Debt - Narrative (Details) $ in Millions	3 Months Ended
Debt - Narrative (Details) $ in Millions	Mar. 31, 2025 USD ($)
Debt Instrument [Line Items]
Financing receivable, transfer	$ 14
Senior unsecured revolving loan facility
Debt Instrument [Line Items]
Additional borrowing capacity	1,300
Senior unsecured revolving loan facility \| Accounts Payable, Inventory Financing
Debt Instrument [Line Items]
Amount owed under revolving loan financing agreement	$ 335

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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+ Details

CDW Corp 10-Q