Stock-Based Compensation - Additional Information (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($) shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options exercisable period	10 years
Total unrecognized compensation expense related to unvested options \| $	$ 0.7
Total unrecognized compensation expense related to unvested options, expects to recognize over estimated weighted average period	2 months 1 day
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation expense related to unvested options, expects to recognize over estimated weighted average period	1 year 8 months 8 days
Total unrecognized compensation expense related to unvested shares of restricted common stock \| $	$ 26.5
Share-based Compensation Award, Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	4 years
Share-based Compensation Award, Tranche One \| Vesting on First Anniversary
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting percentage	25.00%
Share-based Compensation Award, Tranche One \| Vesting Over Succeeding 36 Months
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	36 months
Options vesting percentage	75.00%
Share-based Compensation Award, Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	3 years
Share-based Compensation Award, Tranche Two \| Vesting on First Anniversary
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting percentage	33.33%
Share-based Compensation Award, Tranche Two \| Vesting Over Succeeding 24 Months
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period	24 months
Options vesting percentage	66.66%
Aterian 2014 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance	60,509
2018 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance	257,691
2019 Equity Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for future issuance	0
2019 Equity Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of restricted shares issued and outstanding	70.00%
2019 Equity Plan \| Share-based Compensation Award, Tranche One \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting date	Mar. 13, 2020
2019 Equity Plan \| Share-based Compensation Award, Tranche Two \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting date	Dec. 15, 2020
2019 Equity Plan \| Share-based Compensation Award, Tranche Three \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting date	Jan. 18, 2021
2019 Equity Plan \| Share-based Compensation Award, Tranche Four \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting date	Jul. 01, 2021

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