Impact of Adoption of New Accounting Standards - Balance Sheet (Details) - USD ($)	Jul. 28, 2018	May 01, 2018	Apr. 30, 2018	Jul. 29, 2017	Apr. 30, 2017
Current assets:
Cash and cash equivalents	$ 170,788,000		$ 143,517,000	$ 117,473,000	$ 79,904,000
Short-term investments	118,303,000		113,649,000
Accounts receivable, net of allowance for doubtful accounts of $1,080 at April 30, 2018	13,802,000		56,813,000
Unbilled receivables and retentions (inclusive of related party unbilled receivables of $3,145 at April 30, 2018)	59,870,000		16,872,000
Inventories, net	42,244,000		37,425,000
Prepaid expenses and other current assets	5,196,000		5,103,000
Current assets of discontinued operations			25,668,000
Total current assets	410,203,000		399,047,000
Long-term investments	36,712,000		40,656,000
Property and equipment, net	19,347,000		19,219,000
Deferred income taxes	11,800,000		11,494,000
Other assets	2,299,000		3,002,000
Total assets	480,361,000		473,418,000
Current liabilities:
Accounts payable	12,939,000		21,340,000
Wages and related accruals	10,624,000		16,851,000
Income taxes payable	8,898,000		4,085,000
Customer advances	1,627,000		3,564,000
Other current liabilities	6,664,000		6,954,000
Current liabilities of discontinued operations			9,294,000
Total current liabilities	40,752,000		62,088,000
Deferred rent	1,476,000		1,536,000
Other non-current liabilities	958,000		622,000
Deferred tax liability	67,000		67,000
Liability for uncertain tax positions	49,000		49,000
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.0001 par value: Authorized shares—10,000,000; none issued or outstanding at April 30, 2018
Common stock, $0.0001 par value: Authorized shares—100,000,000 Issued and outstanding shares—23,908,736 at April 30, 2018	2,000		2,000
Additional paid-in capital	170,789,000		170,139,000
Accumulated other comprehensive income (loss)	16,000		(21,000)
Retained earnings	266,243,000		238,913,000
Total AeroVironment stockholders' equity	437,050,000		409,033,000
Noncontrolling interest	9,000		23,000
Total equity	437,059,000		409,056,000
Total liabilities and stockholders' equity	$ 480,361,000		473,418,000
Effect of the Adoption of ASC Topic 606 | ASU 2014-09
Current assets:
Unbilled receivables and retentions (inclusive of related party unbilled receivables of $3,145 at April 30, 2018)			3,796,000
Inventories, net			(1,215,000)
Current assets of discontinued operations			(2,681,000)
Total current assets			(100,000)
Deferred income taxes			326,000
Other assets			281,000
Total assets			507,000
Current liabilities:
Customer advances			1,419,000
Other current liabilities			62,000
Current liabilities of discontinued operations			110,000
Total current liabilities			1,591,000
Stockholders' equity:
Retained earnings		$ (1,084,000)	(1,084,000)
Total AeroVironment stockholders' equity			(1,084,000)
Total equity			(1,084,000)
Total liabilities and stockholders' equity			507,000
As Reported
Current assets:
Cash and cash equivalents				$ 117,473,000	$ 79,904,000
As Reported | ASU 2014-09
Current assets:
Cash and cash equivalents			143,517,000
Short-term investments			113,649,000
Accounts receivable, net of allowance for doubtful accounts of $1,080 at April 30, 2018			56,813,000
Unbilled receivables and retentions (inclusive of related party unbilled receivables of $3,145 at April 30, 2018)			13,076,000
Inventories, net			38,640,000
Prepaid expenses and other current assets			5,103,000
Current assets of discontinued operations			28,349,000
Total current assets			399,147,000
Long-term investments			40,656,000
Property and equipment, net			19,219,000
Deferred income taxes			11,168,000
Other assets			2,721,000
Total assets			472,911,000
Current liabilities:
Accounts payable			21,340,000
Wages and related accruals			16,851,000
Income taxes payable			4,085,000
Customer advances			2,145,000
Other current liabilities			6,892,000
Current liabilities of discontinued operations			9,184,000
Total current liabilities			60,497,000
Deferred rent			1,536,000
Other non-current liabilities			622,000
Deferred tax liability			67,000
Liability for uncertain tax positions			49,000
Stockholders' equity:
Common stock, $0.0001 par value: Authorized shares—100,000,000 Issued and outstanding shares—23,908,736 at April 30, 2018			2,000
Additional paid-in capital			170,139,000
Accumulated other comprehensive income (loss)			(21,000)
Retained earnings			239,997,000
Total AeroVironment stockholders' equity			410,117,000
Noncontrolling interest			23,000
Total equity			410,140,000
Total liabilities and stockholders' equity			$ 472,911,000