Principal Accounting Policies - Summary of the Disaggregated Revenues (Parenthetical) (Detail) - CNY (¥) ¥ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Freight Matching Services [Member]
Disaggregation of Revenue [Line Items]
Revenues attributable to value added tax	¥ 2,580	¥ 1,398	¥ 1,320
Value Added Tax Services [Member]
Disaggregation of Revenue [Line Items]
Revenues attributable to value added tax	¥ 40	¥ 36	¥ 39

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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