Description of Business and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business TuSimple Holdings Inc. (“TuSimple” or the “Company”) is principally engaged in the operation and development of autonomous trucks and an autonomous freight network (“AFN”). The Company is headquartered in San Diego, California..
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The accompanying unaudited condensed consolidated financial statements (“Financial Statements”) have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. The condensed consolidated financial statements include the accounts of the Company and its consolidated subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. These Financial Statements should be read in conjunction with the audited consolidated financial statements and notes as of and for the year ended December 31, 2021, included in the Company's Annual Report on Form 10-K. The condensed consolidated balance sheet as of December 31, 2021, was derived from the audited consolidated financial statements as of that date, but does not include all disclosures required by GAAP. In management’s opinion, the accompanying Financial Statements reflect all normal recurring adjustments necessary for their fair presentation. Other than described below, there have been no changes to the Company’s significant accounting policies described in the Annual Report on Form 10-K for the year ended December 31, 2021 that have had a material impact on the Company’s Financial Statements.
Leases	Leases The Company accounts for leases in accordance with Accounting Standards Codification ("ASC") 842, Leases ("ASC 842"), which requires lessees to recognize on-balance sheet and disclose key information about leasing arrangements. The Company adopted ASC 842 along with all applicable ASU clarifications and improvements on January 1, 2022 using the modified retrospective transition method and used the effective date as the date of initial application. Consequently, financial information is not updated and disclosures required under ASC 842 are not provided for periods before January 1, 2022. ASC 842 provides a number of optional practical expedients in transition. The Company elected the "package of practical expedients," which permits the Company not to reassess under ASC 842 its prior conclusions about lease identification, lease classification and initial direct costs. The Company determines if a contract contains a lease based on whether it has the right to obtain substantially all of the economic benefits from the use of an identified asset and whether it has the right to direct the use of an identified asset in exchange for consideration, which relates to an asset which the Company does not own. Right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. ROU assets are recognized as the lease liability, adjusted for lease incentives received. Lease liabilities are recognized at the present value of the future lease payments at the lease commencement date. The interest rate used to determine the present value of the future lease payments is the Company’s incremental borrowing rate (“IBR”), because the interest rate implicit in most of the Company’s leases is not readily determinable. Lease payments may be fixed or variable, however, only fixed payments or in-substance fixed payments are included in the Company’s lease liability calculation. Variable lease payments are recognized in operating expenses in the period in which the obligation for those payments are incurred. The Company has lease agreements with lease and non-lease components and has elected to utilize the practical expedient to account for lease and non-lease components together as a single combined lease component. Additionally, the Company has determined that certain leases previously identified as build-to-suit leasing arrangements under legacy accounting (ASC 840), were derecognized pursuant to the transition guidance provided for build-to-suit leases in ASC 842. Accordingly, these leases have been reassessed as operating leases as of the adoption date under ASC 842, and are included on the condensed consolidated balance sheet as of March 31, 2022. The Company has leases that include one or more options to extend the lease term for up to five years and some of its leases include options to terminate the lease prior to the end of the agreed upon lease term. For purposes of calculating lease liabilities, lease terms include options to extend or terminate the lease when it is reasonably certain that the Company will exercise such options. Operating leases are included within operating lease ROU assets, operating lease liabilities, current, and operating lease liabilities, noncurrent on the Company's condensed consolidated balance sheet as of March 31, 2022. Finance leases are included in property and equipment, net, accrued expenses and other current liabilities, and other liabilities on the Company's condensed consolidated balance sheets as of March 31, 2022. The Company has elected not to present short-term leases on the consolidated balance sheet as these leases have a lease term of 12 months or less at lease inception and do not contain purchase options or renewal terms that the Company is reasonably certain to exercise. Adoption of the new lease standard on January 1, 2022 impacted the interim unaudited condensed consolidated financial statements as follows: (i) recognition of ROU assets of $32.9 million and lease liabilities of $35.1 million for operating leases, (ii) derecognition of build-to-suit lease assets and liabilities of $6.5 million and $4.4 million, respectively, with the net impact of $0.2 million recorded to accumulated deficit as of January 1, 2022, and (iii) reclassification of deferred rent and other liability balances of $2.5 million relating to its existing lease arrangements into the ROU asset balance as of January 1, 2022. The standard did not materially impact the condensed consolidated statement of operations and condensed consolidated statement of cash flows.
Reclassifications	Reclassifications Certain prior period balances have been reclassified to conform to the current period presentation in the condensed consolidated financial statements and the accompanying notes. Restricted cash has been reclassified to prepaid expenses, other current assets and accrued expenses incurred under joint development agreements have been reclassified to be presented separately from amounts due to related parties, and sales and marketing expense have been reclassified to selling, general and administrative expense.
Recently Adopted and Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements In February 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2016-02, Leases, to require lessees to recognize all leases, with limited exceptions, on the balance sheet, while recognition on the statement of operations will remain similar to legacy lease accounting, ASC 840. Subsequently, the FASB issued ASU No. 2018-10, Codification Improvements to Topic 842, ASU No. 2018-11, Targeted Improvements, ASU No. 2018-20, Narrow-Scope Improvements for Lessors, and ASU 2019-01, Codification Improvements, to clarify and amend the guidance in ASU No. 2016-02. As disclosed above, the Company adopted the ASUs on January 1, 2022 on a modified retrospective basis. Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments, as amended by subsequently issued ASUs 2018-19, 2019-04, 2019-05, 2019-10 2019-11 and 2020-02 and 2020-03 (collectively, “Topic 326”), which requires an entity to utilize a new impairment model known as the current expected credit loss (“CECL”) model to estimate its lifetime “expected credit loss” and record an allowance that, when deducted from the amortized cost basis of the financial asset, presents the net amount expected to be collected on the financial asset. The CECL model is expected to result in more timely recognition of credit losses. This guidance also requires new disclosures for financial assets measured at amortized cost, loans and available-for-sale debt securities. For the Company, the new standard is effective for annual reporting periods beginning after December 15, 2022, including interim periods within those annual periods. Early adoption is permitted. Entities will apply the standard’s provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. The Company is currently evaluating the impact the adoption of this standard will have on its consolidated financial statements. In October 2020, the FASB issue ASU No. 2020-10, Codification Improvements, which updates various codification topics by clarifying or improving disclosure requirements to align with the SEC’s regulations. For the Company, the new standard will be effective for annual reporting periods beginning after December 15, 2021 and interim periods within fiscal years beginning after December 15, 2022. The Company is currently evaluating the impact the adoption of this standard will have on its consolidated financial statements.