| Member's/Stockholder's Equity (Deficit) - Summary of Ownership of XPO LLC (Details) | 9 Months Ended | 
|---|---|
| Sep. 30, 2021  shares | |
| Subsidiary of Limited Liability Company or Limited Partnership [Line Items] | |
| Units Owned | 46,861,288 | 
| XPO Inc. | |
| Subsidiary of Limited Liability Company or Limited Partnership [Line Items] | |
| Units Owned | 23,898,042 | 
| Redeemable Noncontrolling Interests | |
| Subsidiary of Limited Liability Company or Limited Partnership [Line Items] | |
| Units Owned | 22,963,246 | 
| XPO LLC | |
| Subsidiary of Limited Liability Company or Limited Partnership [Line Items] | |
| Ownership percentage | 100.00% | 
| XPO LLC | XPO Inc. | |
| Subsidiary of Limited Liability Company or Limited Partnership [Line Items] | |
| Ownership percentage | 51.00% | 
| XPO LLC | Redeemable Noncontrolling Interests | |
| Subsidiary of Limited Liability Company or Limited Partnership [Line Items] | |
| Ownership percentage | 49.00% | 
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- Definition Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Number of stock or units eligible for distribution to members or limited partners of the limited liability company (LLC) or limited partnership (LP). No definition available. 
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- Definition 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. No definition available. 
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