Stockholders' Equity - Narrative (Details) $ / shares in Units, $ in Thousands					3 Months Ended		9 Months Ended
	May 15, 2023 USD ($) shares	May 09, 2023 USD ($) shares	May 08, 2023 USD ($) shares	Feb. 28, 2023 USD ($)	Sep. 30, 2023 USD ($) classOfStock vote $ / shares shares	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) classOfStock vote $ / shares shares	Sep. 30, 2022 USD ($)	Dec. 31, 2022 shares
Class of Stock [Line Items]
Number of classes of stock | classOfStock					2		2
Sale of stock, gross proceeds | $					$ 904	$ 1,102	$ 2,553	$ 2,846
Vendor payments in shares in lieu of cash (in shares)							6,505,012
Vendor payments in stock in lieu of cash, liability | $					$ 6,100		$ 6,100
Pony. AI, Inc
Class of Stock [Line Items]
Vendor payments in shares in lieu of cash (in shares)							1,564,822
Private Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares)									1,668,269
Warrants exercised (in shares)					0		0
Share per warrant (in shares)					1		1
Stock price of warrants (in dollars per share) | $ / shares					$ 11.50		$ 11.50
Equity Financing Program
Class of Stock [Line Items]
Stock issuance sales agreement, authorized offering amount | $				$ 75,000
Sale of stock, gross proceeds | $					$ 9,107		$ 38,711
Class A Common Stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)					715,000,000		715,000,000
Common stock, par value (in dollars per share) | $ / shares					$ 0.0001		$ 0.0001
Common stock, shares issued (in shares)					325,908,478		325,908,478
Common stock, shares outstanding (in shares)					304,045,028		304,045,028
Common stock, votes per share | vote					1		1
Sale of stock, shares issued in transaction	1,652,892		1,652,892
Sale of stock, gross proceeds | $	$ 10,000		$ 10,000
Granted (in shares)		1,652,892
Option to purchase additional shares granted amount | $		$ 10,000
Class A Common Stock | Equity Financing Program
Class of Stock [Line Items]
Sale of stock (in shares)					1,833,829		5,599,121
Sale of stock, gross proceeds | $					$ 9,100		$ 38,700
Common stock available for future issuance | $					$ 35,900		$ 35,900
Class B Common Stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)					121,000,000		121,000,000
Common stock, par value (in dollars per share) | $ / shares					$ 0.0001		$ 0.0001
Common stock, shares issued (in shares)					97,088,670		97,088,670
Common stock, shares outstanding (in shares)					97,088,670		97,088,670
Common stock, votes per share | vote					10		10