XML 40 R30.htm IDEA: XBRL DOCUMENT v3.22.2.2
Summary of Significant Accounting Policies - Additional Information (Details)
 3 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended
Sep. 02, 2020
$ / shares
Sep. 30, 2022
USD ($)
$ / shares
shares
Sep. 30, 2021
USD ($)
Jun. 30, 2021
shares
Sep. 30, 2022
USD ($)
Segment
$ / shares
shares
Sep. 30, 2021
USD ($)
Dec. 31, 2021
USD ($)
$ / shares
Sep. 30, 2018
Agreement
Summary Of Significant Accounting Policies [Line Items]                
Goodwill or other intangible assets   $ 0     $ 0      
Number of operating agreements of joint venture parties | Agreement               2
Restricted cash   17,500,000     17,500,000   $ 17,500,000  
Cancellation charges incurred related to purchase of equipment   11,300,000     11,300,000      
Impairment of long-lived assets   7,800,000     $ 7,806,000      
Number of reportable segment | Segment         1      
Number of operating segment | Segment         1      
Provision for income taxes   0 $ 0   $ 0 $ 0    
Current income tax expense (benefit)   0 0   0 0    
Deferred income tax expense (benefit)   0 $ 0   0 $ 0    
Accrued Liabilities                
Summary Of Significant Accounting Policies [Line Items]                
Estimated loss contingency   $ 3,500,000     $ 3,500,000      
Legacy Quantum Scape                
Summary Of Significant Accounting Policies [Line Items]                
Business combination, effective date of acquisition         Nov. 25, 2020      
Business combination, date of acquisition agreement         Sep. 02, 2020      
Business combination exchange ratio 4.02175014920              
Public Warrants                
Summary Of Significant Accounting Policies [Line Items]                
Warrant exercisable number of shares | shares   1     1      
Warrants sold | shares         11,499,989      
Warrants exercise price per share | $ / shares   $ 11.50     $ 11.50      
Minimum percentage of class A stockholders required for settlement of shares   50.00%     50.00%      
Private Placement Warrants                
Summary Of Significant Accounting Policies [Line Items]                
Warrants sold | shares         6,650,000      
Warrant issued in connection with the closing of business combination | shares         75,000      
Class A Common Stock                
Summary Of Significant Accounting Policies [Line Items]                
Common stock, par value | $ / shares   $ 0.0001     $ 0.0001   $ 0.0001  
Number of shares purchased | shares         218,200      
Class A Common Stock | Legacy Quantum Scape                
Summary Of Significant Accounting Policies [Line Items]                
Common stock, par value | $ / shares $ 0.0001              
Class A Common Stock | 2020 Equity Employee Stock Purchase Plan                
Summary Of Significant Accounting Policies [Line Items]                
Common stock reserved for future issuance | shares   11,600,000     11,600,000      
Class A Common Stock | 2020 Equity Employee Stock Purchase Plan | Maximum                
Summary Of Significant Accounting Policies [Line Items]                
Purchase of common stock | shares       1,000        
Class B Common Stock                
Summary Of Significant Accounting Policies [Line Items]                
Common stock, par value | $ / shares   $ 0.0001     $ 0.0001   $ 0.0001  
Class B Common Stock | Legacy Quantum Scape                
Summary Of Significant Accounting Policies [Line Items]                
Common stock, par value | $ / shares $ 0.0001              
US Government Money Market Fund and Marketable Securities                
Summary Of Significant Accounting Policies [Line Items]                
Investment securities   $ 231,900,000     $ 231,900,000   $ 227,800,000  
U.S. Government and Agency Securities                
Summary Of Significant Accounting Policies [Line Items]                
Investment securities   616,500,000     $ 616,500,000   $ 722,300,000  
JVA                
Summary Of Significant Accounting Policies [Line Items]                
Percentage of joint venture holders voting interest         21.60%   19.80%  
Contribution in exchange for equity interests   $ 1,700,000     $ 1,700,000      
Equity interests percentage   50.00%     50.00%