General form of registration statement for all companies including face-amount certificate companies

Summary of Significant Accounting Policies - Net Loss per Common Share (Details)

v3.21.1
Summary of Significant Accounting Policies - Net Loss per Common Share (Details) - shares
 3 Months Ended 6 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Sep. 30, 2020
Sep. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share            
Shares excluded from the calculation of weighted average dilutive common shares because their inclusion would have been anti-dilutive 14,166,667     14,166,667    
Blade Urban Air Mobility [Member] | Stock Option            
Antidilutive Securities Excluded from Computation of Earnings Per Share            
Shares excluded from the calculation of weighted average dilutive common shares because their inclusion would have been anti-dilutive   13,323,315 11,754,833   10,040,803 7,793,765
Blade Urban Air Mobility [Member] | Convertible Preferred Stock            
Antidilutive Securities Excluded from Computation of Earnings Per Share            
Shares excluded from the calculation of weighted average dilutive common shares because their inclusion would have been anti-dilutive   22,116,811 22,116,811   22,116,811 22,116,811