Capital Structure - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023 $ / shares shares	Dec. 31, 2022 $ / shares shares	Mar. 12, 2021 shares
Class Of Stock [Line Items]
Preferred stock, par value | $ / shares	$ 0.0001
Temporary equity, shares authorized	432,000,000		432,000,000
Common stock, shares authorized	422,000,000	422,000,000	422,000,000
Preferred stock, shares authorized	10,000,000		10,000,000
Preferred Stock, Conversion Basis	1:1 basis
Description of prior to business combination	Prior to the Business Combination, Aeva had shares of $0.001 par value Series Seed, Series A, Series A-1, and Series B preferred stock outstanding, all of which were convertible into shares of common stock of the pre-combination Aeva on a 1:1 basis, subject to certain anti-dilution protections. Upon the Closing, the outstanding shares of preferred stock were converted into common stock of Aeva, Inc., and then into common stock of the Company at a ratio of 1:9.07659, the exchange rate established in the BCA.
Preferred stock, shares issued	0
Pre-combination Aeva preferred stock outstanding	0
Common Stock Par Or Stated Value Per Share | $ / shares	$ 0.0001	$ 0.0001
Minimum
Class Of Stock [Line Items]
Conversion Ratio	1
Maximum
Class Of Stock [Line Items]
Conversion Ratio	9.07659
Series B Preferred Stock [Member]
Class Of Stock [Line Items]
Preferred stock, par value | $ / shares	$ 0.001
Public Warrants [Member]
Class Of Stock [Line Items]
Class of Warrant or Right, Outstanding	12,074,876
Common Stock Par Or Stated Value Per Share | $ / shares	$ 11.5
Series A warrants [Member]
Class Of Stock [Line Items]
Class of Warrant or Right, Outstanding	15,000,000
Common Stock Par Or Stated Value Per Share | $ / shares	$ 1
Private Warrants [Member]
Class Of Stock [Line Items]
Class of Warrant or Right, Outstanding	384,000
Common Stock Par Or Stated Value Per Share | $ / shares	$ 11.5