Stockholders’ Equity - Summary of Common Stock Outstanding (Details) - shares	Sep. 30, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)	195,922,639	175,912,194
Converted pre-combination Velodyne common stock outstanding
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)	85,561,252	101,849,247
Converted pre-combination Velodyne preferred stock outstanding
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)	24,772,759	24,772,759
Graf Founder shares
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)	157,900	2,575,000
Other stockholders
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)	85,430,728	46,715,188