Organization and Significant Accounting Policies Other (Details)			12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Apr. 30, 2018 USD ($) item shares	Apr. 30, 2017 USD ($) shares	Apr. 30, 2016 USD ($) shares
Self-Insurance Liability
Estimated self-insurance liability of employee medical claim			$ 1,003,000	$ 1,133,000
Income Taxes
U.S. federal statutory income tax rate (as a percent)	21.00%	35.00%	30.40%	34.00%	35.00%
Deferred tax expense			$ 3,400,000
Revenue Recognition
Number of key factors that impact reliability of management's estimates for revenue recognition | item			2
Maximum term of contract, considered as a factor in management estimates			6 months
Research and Development
Revenue from customer funded research and development			$ 51,848,000	$ 43,615,000	$ 53,546,000
Cost of sales			36,415,000	29,790,000	34,786,000
Research and Development With Federal Government
Total estimated costs			14,200,000
Funding			6,100,000
Reimbursement amount			8,100,000
Reimbursements under the contract			4,188,000	233,000
Foreign Currency Transaction [Abstract]
Foreign currency gain (loss)			87,000	(284,000)	(63,000)
Advertising Costs
Advertising expenses			526,000	227,000	232,000
Numerator for basic earnings per share:
Continuing operations attributable to AeroVironment			22,576,000	16,633,000	15,393,000
Discontinued operations, net of tax			(2,508,000)	(4,154,000)	(6,427,000)
Net income attributable to AeroVironment			$ 20,068,000	$ 12,479,000	$ 8,966,000
Denominator for basic (loss) earnings per share:
Weighted-average common shares outstanding, excluding unvested restricted stock (in shares) | shares			23,471,241	23,059,045	22,936,413
Dilutive effect of employee stock options and unvested restricted stock (in shares) | shares			342,531	248,693	217,080
Denominator for diluted (loss) earnings per share (in shares) | shares			23,813,772	23,307,738	23,153,493
Number of shares reserved for issuance that are anti-dilutive | shares			22,000	86,000	22,000