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

Reverse Capitalization - Summary of Number of Shares of Common Stock Issued (Detail)

v3.22.1
Reverse Capitalization - Summary of Number of Shares of Common Stock Issued (Detail)
Dec. 31, 2021
shares
Old Spire Common Stock  
Class Of Stock [Line Items]  
Common stock, Issued 6,405,302
Old Spire Convertible Preferred Stock  
Class Of Stock [Line Items]  
Common stock, Issued 42,873,636
Old Spire Convertible Note  
Class Of Stock [Line Items]  
Common stock, Issued 37,034,620
Old Spire Warrants Excluding Eib Warrants  
Class Of Stock [Line Items]  
Common stock, Issued 672,355
Class A Common Shares To Old Spire Stockholders  
Class Of Stock [Line Items]  
Common stock, Issued 86,985,913
New Spire Class A Common Stock Issued To Old Spire Founders  
Class Of Stock [Line Items]  
Common stock, Issued 12,058,614
New Spire Class A Common Stock Issued To Pipe Investors  
Class Of Stock [Line Items]  
Common stock, Issued 24,500,000
New Spire Class A Common Stock Held By Public Stockholders  
Class Of Stock [Line Items]  
Common stock, Issued 1,979,515
New Spire Class A Common Stock Issued To Fp Lenders  
Class Of Stock [Line Items]  
Common stock, Issued 2,468,492
New Spire Class A Common Stock Resulting From Conversion Of Navsight Class B Common Stock  
Class Of Stock [Line Items]  
Common stock, Issued 5,750,000
Class A Common Shares And Old Spire And New Spire Shares  
Class Of Stock [Line Items]  
Common stock, Issued 133,742,534
New Spire Class B Common Stock Issued To Old Spire Founders  
Class Of Stock [Line Items]  
Common stock, Issued 12,058,614
New Spire Common Stock  
Class Of Stock [Line Items]  
Common stock, Issued 145,801,148