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Summary of Significant Accounting Policies - Narrative (Details) |  | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Aug. 12, 2021 USD ($) | Jun. 30, 2024 USD ($) $ / shares shares | Jun. 30, 2023 USD ($) | Mar. 31, 2023 USD ($) | Jun. 30, 2024 USD ($) segment $ / shares shares | Jun. 30, 2023 USD ($) | Dec. 31, 2023 USD ($) | Mar. 04, 2024 | Jan. 12, 2024 $ / shares
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Restricted cash, non-current |  | $ 380,000 |  |  | $ 380,000 |  | $ 373,000 |  |
Deferred fulfillment and prepaid launch costs |  | 400,000 |  |  | 400,000 |  | 1,700,000 |  |
Contract with customer, cumulative catch-up to revenue |  | 1,200,000 | $ 0 |  | 1,700,000 | $ 0 |  |  |
Contract with customer, liability |  | 1,100,000 |  |  | 1,100,000 |  | 1,000,000.0 |  |
Contract liabilities, non-current |  | 618,000 |  |  | 618,000 |  | 998,000 |  |
Service revenue |  | $ 1,209,000 | $ 1,705,000 |  | $ 1,722,000 | 1,727,000 |  |  |
Contract with customer, liability |  |  |  |  |  |  | 35,000 |  |
Warrants and rights outstanding, term (in years) |  | 5 years |  |  | 5 years |  |  | 5 years | 5 years
Payment of liability |  |  |  | $ 10,000,000 |  |  |  |  |
Exercise price (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  | $ 0.96
Estimated fair value of warrants |  | $ 3,000 |  |  | $ 3,000 |  | 3,000 |  |
Impairments of long-lived assets |  |  |  |  | 0 | $ 0 |  |  |
Defined contribution plan, cost |  |  |  |  | $ 0 |  |  |  |
Number of reportable segments | segment |  |  |  |  | 1 |  |  |  |
Number of operating segments | segment |  |  |  |  | 1 |  |  |  |
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | Geographic Distribution, Domestic |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Percentage of derived from customers |  |  |  |  | 98.00% |  |  |  |
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | Geographic Distribution, Foreign |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Percentage of derived from customers |  |  |  |  | 2.00% |  |  |  |
Common Class A |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Exchange ratio |  | 1 |  |  | 1 |  |  |  |
Exercise price (in dollars per share) | $ / shares |  | $ 575.00 |  |  | $ 575.00 |  |  |  |
Expiration period |  |  |  |  | 5 years |  |  |  |
ESPP |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Offering period |  |  |  |  | 6 months |  |  |  |
Restricted Stock Units |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Expected term |  |  |  |  | 6 months |  |  |  |
Private Placement Warrant |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Number of warrants outstanding (in shares) | shares |  | 225,450 |  |  | 225,450 |  |  |  |
Estimated fair value of warrants | $ 31,200,000 |  |  |  |  |  |  |  |
Public Warrant |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Number of warrants outstanding (in shares) | shares |  | 172,500 |  |  | 172,500 |  |  |  |
Equity related to warrants | $ 20,200,000 |  |  |  |  |  |  |  |
Prepaid Expenses and Other Current Assets |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Deferred fulfillment and prepaid launch costs |  | $ 0 |  |  | $ 0 |  | 1,300,000 |  |
Other Noncurrent Assets |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Deferred fulfillment and prepaid launch costs |  | $ 400,000 |  |  | $ 400,000 |  | $ 400,000 |  |
Patents |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Intangible asset useful life |  | 10 years |  |  | 10 years |  |  |  |
Cash Designated for Collateral |  |  |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |  |  |
Restricted cash, non-current |  | $ 400,000 |  |  | $ 400,000 |  |  |  |

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