Notes Payable - Narrative Part 2 (Details) $ / shares in Units, $ in Thousands				3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 05, 2024 USD ($) $ / shares shares	Aug. 02, 2024 USD ($) $ / shares	May 08, 2023 $ / shares	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) trading_day $ / shares shares	Sep. 30, 2023 USD ($) shares	Dec. 31, 2023 USD ($) $ / shares shares	Jul. 31, 2024 $ / shares	Jun. 30, 2024 $ / shares	May 09, 2023 $ / shares	Feb. 03, 2023 $ / shares
Debt Instrument [Line Items]
Exercise price (in dollars per share) | $ / shares									$ 110,400
Warrants exercised (in shares) | shares						0
Notes Payable
Debt Instrument [Line Items]
Fair value measurement with unobservable inputs reconciliation, recurring basis, liability, settlements				$ 100	$ 0	$ 200	$ 2,500
Change in fair value of earnout liability						$ (35,992)
SPA Warrants
Debt Instrument [Line Items]
Aggregate shares able to be purchased from warrants issued (in shares) | shares				15,143		15,143		13,906
Term of warrants				7 years		7 years
Warrants exercised (in shares) | shares				0		0
Junior SPA Warrants
Debt Instrument [Line Items]
Exercise price (in dollars per share) | $ / shares	$ 6.29
Aggregate shares able to be purchased from warrants issued (in shares) | shares				5,931,638		5,931,638
Term of warrants	5 years			5 years		5 years
Repurchase price (in dollars per share) | $ / shares				$ 0.01		$ 0.01
Warrants exercised (in shares) | shares				0		0
Percent of purchaser's conversion shares	100.00%
Junior SPA Warrants | Minimum
Debt Instrument [Line Items]
Number of trading days | trading_day						20
Junior SPA Warrants | Maximum
Debt Instrument [Line Items]
Number of trading days | trading_day						30
Placement Agent
Debt Instrument [Line Items]
Warrant liabilities1	$ 600
Incremental Warrants
Debt Instrument [Line Items]
Term of warrants	1 year
Class A Common Stock
Debt Instrument [Line Items]
Share price (in dollars per share) | $ / shares				$ 144,000		$ 144,000
Class A Common Stock | Common Stock
Debt Instrument [Line Items]
Exercise of warrants (in shares) | shares							5,326
Class A Common Stock | Notes Payable
Debt Instrument [Line Items]
Conversion of notes to Class A common stock						$ 44,891
Class A Common Stock | SPA Warrants
Debt Instrument [Line Items]
Exercise price (in dollars per share) | $ / shares	$ 5.24			5.24		$ 5.24		$ 29.33		$ 29.33
Class A Common Stock | SPA Warrants | Common Stock
Debt Instrument [Line Items]
Exercise of warrants (in shares) | shares								6,292
Class A Common Stock | Junior SPA Warrants
Debt Instrument [Line Items]
Exercise price (in dollars per share) | $ / shares				6.29		6.29
Aggregate shares able to be purchased from warrants issued (in shares) | shares	202,768
Share price (in dollars per share) | $ / shares				$ 12.58		$ 12.58
Notes Payable | SPA Warrants
Debt Instrument [Line Items]
Notes payable1				$ 0	1,700	$ 0	$ 1,700
Notes Payable | Junior SPA Warrants
Debt Instrument [Line Items]
Notes payable1				13,400		13,400
SPA Notes
Debt Instrument [Line Items]
Conversion price (in dollars per share) | $ / shares			$ 10,080								$ 8,568
Loss on settlement of notes payable					11,400		11,400
Debt instrument, floor price (in dollars per share) | $ / shares			$ 2,016								$ 960.00
Change in fair value of earnout liability				10,900	22,300	56,700	95,100
SPA Notes | Class A Common Stock | Notes Payable
Debt Instrument [Line Items]
Conversion of notes to Class A common stock						44,900	125,300
SPA Notes | Notes Payable
Debt Instrument [Line Items]
Conversion price (in dollars per share) | $ / shares		$ 29.33										$ 10,080
Proceeds from notes payable, net of original issuance discount						8,500		$ 231,100
Fair value measurement with unobservable inputs reconciliation, recurring basis, liability, settlements				56,400	32,100	147,100	207,700
Notes payable1				41,100	$ 95,400	41,100	95,400
Debt conversion, converted instrument, amount						96,300	$ 200,400
SPA Notes | Notes Payable | Make-Whole Amount
Debt Instrument [Line Items]
Accrued interest		$ 0
Loss on settlement of notes payable				$ (2,800)		$ (2,800)
SPA Notes | Notes Payable | Class A Common Stock
Debt Instrument [Line Items]
Conversion price (in percent)		90.00%	90.00%
Secured SPA Notes | Notes Payable
Debt Instrument [Line Items]
Debt instrument, floor price (in dollars per share) | $ / shares		$ 435.84						$ 435.84
Secured SPA Notes | Notes Payable | Minimum
Debt Instrument [Line Items]
Contractual Interest Rates				10.00%		10.00%		10.00%
Secured SPA Notes | Notes Payable | Maximum
Debt Instrument [Line Items]
Contractual Interest Rates				15.00%		15.00%		15.00%
Secured SPA Notes | Notes Payable | Make-Whole Amount
Debt Instrument [Line Items]
Conversion price (in percent)		90.00%	90.00%
Junior Secured Notes | Notes Payable
Debt Instrument [Line Items]
Fair value measurement with unobservable inputs reconciliation, recurring basis, liability, settlements				$ 600		$ 600
Junior Secured Notes | Notes Payable
Debt Instrument [Line Items]
Conversion price (in dollars per share) | $ / shares	$ 5.24
Debt instrument, floor price (in dollars per share) | $ / shares	$ 1.05
Proceeds from notes payable, net of original issuance discount						13,250
Notes payable1				9,400		9,400
Fair value, option, notes payable, aggregate amount	$ 30,000			$ 20,800		$ 20,800
Payments for secured debt purchased under agreements	22,500
Fair value, option, noncash proceeds from sale of notes payable	$ 7,500
Contractual Interest Rates				10.00%		10.00%
Junior Secured SPA Notes and Junior SPA Warrants
Debt Instrument [Line Items]
Change in fair value of notes payable and warrant liabilities				$ (3,700)		$ (3,700)