Stockholders' Equity - Narrative (Details)					1 Months Ended	12 Months Ended
	Dec. 21, 2021 shares	Jul. 01, 2021 shares	Mar. 16, 2021 USD ($) $ / shares shares	Dec. 02, 2020 USD ($) vote shares	Dec. 31, 2021 USD ($) vote $ / shares shares	Dec. 31, 2021 USD ($) vote $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares	Mar. 31, 2021 shares	Dec. 03, 2020 $ / shares shares	Dec. 31, 2018 shares	Dec. 31, 2015 shares
Class of Stock [Line Items]
Common stock, shares issued (in shares)										323,936,240
Common stock, shares outstanding (in shares)										323,936,240
Compensation expense | $						$ 77,684,000	$ 8,711,000	$ 2,702,000
Treasury stock, shares outstanding (in shares)					15,263,761	15,263,761	0
Preferred stock, shares outstanding (in shares)					0	0
Proceeds from exercise of warrants | $						$ 153,927,000	$ 0	0
Change in fair value of warrant liabilities | $						$ (26,126,000)	(268,266,000)	(256,000)
Vendor payments in shares in lieu of cash (in shares)						291,940
Vendor stock-in-lieu of cash program | $					$ 1,000,000	$ 1,000,000
Research and development
Class of Stock [Line Items]
Compensation expense | $						20,216,000	$ 2,098,000	$ 914,000
Daimler North America Corporation
Class of Stock [Line Items]
Prepaid expenses and other current assets | $					$ 5,200,000	5,200,000
Daimler North America Corporation | Research and development
Class of Stock [Line Items]
Compensation expense | $						$ 700,000
Private and Public Warrants
Class of Stock [Line Items]
Proceeds from exercise of warrants | $			$ 153,900,000
Public Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares)					0	0	13,333,309
Warrants exercised (in shares)									13,128,671
Remaining warrants redeemed (in shares)			204,638
Redemption price per warrant (in dollars per share) | $ / shares			$ 0.01
Private Warrants
Class of Stock [Line Items]
Warrants outstanding (in shares)					3,077,021	3,077,021	6,666,666
Warrants exercised (in shares)			3,589,645
Stock price of warrants (in dollars per share) | $ / shares					$ 11.50	$ 11.50
Other Current Liabilities
Class of Stock [Line Items]
Purchase transaction | $						$ 4,300,000
Founders Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)												26,206,837
Conversion ratio												1
Preferred stock, shares outstanding (in shares)					0	0	0	26,206,837			26,206,837
Chief Executive Officer | Gores Metropoulos
Class of Stock [Line Items]
Compensation expense | $				$ 3,000,000
Chief Executive Officer | Gores Metropoulos | Founders Preferred Stock
Class of Stock [Line Items]
Shares converted (in shares)				22,935,412
Class A Common Stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)					715,000,000	715,000,000	715,000,000
Common stock, par value (in dollars per share) | $ / shares					$ 0.0001	$ 0.0001	$ 0.0001			$ 0.0001
Common stock, shares issued (in shares)					266,076,525	266,076,525	218,818,037			218,818,037
Common stock, shares outstanding (in shares)					250,812,764	250,812,764	218,818,037			218,818,037
Common stock, votes per share | vote					1	1
Shares converted (in shares)		10,500,000
Shares repurchased (in shares) | $					$ 312,500,000	$ 312,500,000
Treasury stock, shares outstanding (in shares)					15,263,761	15,263,761
Purchase transaction | $					$ 235,900,000
Class A Common Stock | Daimler North America Corporation
Class of Stock [Line Items]
Shares issued for services (in shares)						1,500,000
Award vesting period (in years)						2 years
Class A Common Stock | Common Stock
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)					266,076,525	266,076,525	218,818,037	139,635,890			134,337,450
Shares issued for services (in shares)						291,940
Class A Common Stock | Chief Executive Officer | Gores Metropoulos
Class of Stock [Line Items]
Common stock, votes per share | vote				1
Class A Common Stock | Chief Executive Officer | Gores Metropoulos | Common Stock
Class of Stock [Line Items]
Shares converted (in shares)				82,182,791
Class B Common Stock
Class of Stock [Line Items]
Common stock, shares authorized (in shares)					121,000,000	121,000,000	121,000,000
Common stock, par value (in dollars per share) | $ / shares					$ 0.0001	$ 0.0001	$ 0.0001			$ 0.0001
Common stock, shares issued (in shares)					97,088,670	97,088,670	105,118,203			105,118,203
Common stock, shares outstanding (in shares)					97,088,670	97,088,670	105,118,203			105,118,203
Common stock, votes per share | vote					10	10
Shares issued upon conversion (in shares)	4,500,000
Class B Common Stock | Common Stock
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)					97,088,670	97,088,670	105,118,203	0			0
Class B Common Stock | Chief Executive Officer | Gores Metropoulos
Class of Stock [Line Items]
Common stock, votes per share | vote				10