Post-effective amendment to a registration statement that is not immediately effective upon filing

Reverse Capitalization - Additional Information (Detail)

v3.22.1
Reverse Capitalization - Additional Information (Detail)
$ / shares in Units, $ in Thousands
 1 Months Ended 12 Months Ended
Aug. 16, 2021
$ / shares
shares
Aug. 31, 2021
USD ($)
$ / shares
shares
Dec. 31, 2021
USD ($)
$ / shares
Dec. 31, 2020
USD ($)
Class Of Stock [Line Items]        
Common stock, par value per share | $ / shares     $ 0.0001  
Proceeds from issuance initial public offering   $ 264,823    
Cash held in trust account   230,027    
Proceeds from Issuance or Sale of Equity   210,204    
Proceeds from issuance of financial Services obligations   245,000    
Payments of merger related costs   38,569    
Payments of Financing Costs     $ 4,717 $ 808
Selling, General and Administrative Expenses        
Class Of Stock [Line Items]        
Payments of Financing Costs   6,591    
Additional Paid In Capitals        
Class Of Stock [Line Items]        
Payments of merger related costs   $ 31,978    
First Tranches Share Trading Price [Member]        
Class Of Stock [Line Items]        
Share price | $ / shares   $ 13.00    
Second Tranches Share Trading Price [Member]        
Class Of Stock [Line Items]        
Share price | $ / shares   16.00    
Third Tranches Share Trading Price [Member]        
Class Of Stock [Line Items]        
Share price | $ / shares   19.00    
Fourth Tranches Share Trading Price [Member]        
Class Of Stock [Line Items]        
Share price | $ / shares   $ 22.00    
Old Spire Options [Member]        
Class Of Stock [Line Items]        
Exchange ratio of common stock   1.8282    
Number of consecutive trading days for determining share price   20 days    
Number of trading days for determining share price   30 days    
Closing date of warrants       5 years
Class Of Warrants and Rights Exchange Ratio   1.7058    
Pipe Investors        
Class Of Stock [Line Items]        
Payments of stock issuance costs   $ 7,142    
Pipe Investors | Pipe Subscription Agreements        
Class Of Stock [Line Items]        
Shares issued during the year, subscribed | shares   24,500,000    
Shares issued during the year, aggregate purchase price   $ 245,000    
Old Spire Warrants        
Class Of Stock [Line Items]        
Class of Warrant or Right, Outstanding | shares 909,798      
Old Spire Convertible Notes        
Class Of Stock [Line Items]        
Debt Instrument convertible conversion ratio 2.4808      
Two Thousand Twenty One Old Spire Notes        
Class Of Stock [Line Items]        
Debt Instrument convertible conversion ratio 13.6466      
Old Spire Series A Convertible Preferred Stock        
Class Of Stock [Line Items]        
Outstanding shares | shares 12,671,911      
Common stock, conversion basis one-to-one basis      
Old Spire Series B Convertible Preferred Stock        
Class Of Stock [Line Items]        
Outstanding shares | shares 4,869,754      
Common stock, conversion basis one-to-one basis      
Old Spire Series C Convertible Preferred Stock        
Class Of Stock [Line Items]        
Outstanding shares | shares 7,592,402      
Common stock, conversion basis one-to-one basis      
New Spire Class A Common Stock [Member]        
Class Of Stock [Line Items]        
Common stock, par value per share | $ / shares $ 0.0001      
Exchange ratio of common stock   1.7058    
Shares issued, price per share | $ / shares   $ 0.1236    
New Spire Class B Common Stock Member | Old Spire Founders        
Class Of Stock [Line Items]        
Common stock, par value per share | $ / shares   $ 0.0001    
Shares purchased by related party | shares   12,058,614