Net Loss Per Share Attributable to Common Stockholders - Summary of Potentially Dilutive Securities (Details) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive common stock equivalents have been excluded from the computation of diluted net loss per share	18,100,000	68,109,671
Preferred Stock [Member] | Old Owlet [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive common stock equivalents have been excluded from the computation of diluted net loss per share		61,809,312
Common Stock Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive common stock equivalents have been excluded from the computation of diluted net loss per share	18,100,000
Common Stock Warrants [Member] | Old Owlet [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive common stock equivalents have been excluded from the computation of diluted net loss per share		942,623
Preferred Stock Warrants [Member] | Old Owlet [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive common stock equivalents have been excluded from the computation of diluted net loss per share		889,765
Convertible Notes [Member] | Old Owlet [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive common stock equivalents have been excluded from the computation of diluted net loss per share		4,467,971