CytoDyn Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

Summary of Significant Accounting Policies - Additional Information (Detail)		2 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Nov. 01, 2017 shares	Feb. 28, 2018 USD ($) shares	Feb. 28, 2018 USD ($) shares	Feb. 28, 2017 USD ($)	Feb. 28, 2018 USD ($) shares	Feb. 28, 2017 USD ($) shares	Dec. 31, 2017	May 31, 2017 USD ($) shares	Aug. 24, 2017 shares	Aug. 24, 2016 shares	Aug. 23, 2016 shares	Apr. 30, 2010 shares
Summary Of Significant Accounting Policies [Line Items]
Net loss			$ (17,950,100)	$ (8,112,432)	$ (40,526,058)	$ (18,934,153)
Accumulated (deficit)		$ (163,515,773)	(163,515,773)		(163,515,773)			$ (122,989,715)
Balance in excess of federally insured limits		5,200,000	5,200,000		5,200,000			1,500,000
Impairment charges			0	0	0	$ 0
Pre-launch inventory qualified for capitalization		$ 0	$ 0		$ 0			$ 0
Estimated future unvested forfeitures					0.00%
Common stock, shares authorized \| shares	200,000,000	375,000,000	375,000,000		375,000,000			350,000,000	375,000,000	350,000,000	250,000,000	100,000,000
Amortization of discount on convertible notes					$ 1,666,017
Direct costs associated with the convertible notes					400,000
Amortization of debt issuance costs					$ 435,609
Common stock options and warrants to purchase \| shares					130,457,331	77,509,269
Unrecognized benefits		$ 0	$ 0		$ 0
Federal statutory income tax rate, percent		21.00%					35.00%
Effective income tax rate reconciliation, at blended income tax rate, percent		29.00%
Tax cuts and jobs act of 2017, incomplete accounting, change in tax rate, deferred tax liability, provisional income tax benefit					14,270,089
Provision for taxes on income			0	$ 0	0	$ 0
Equity Securities
Summary Of Significant Accounting Policies [Line Items]
Deferred offering costs		$ 700,000	700,000		700,000			$ 1,800,000
Short-Term Convertible Notes
Summary Of Significant Accounting Policies [Line Items]
Debt discount								92,000
Amortization of debt issuance costs					400,000
Short-Term Convertible Notes \| Detachable Common Stock Warrants
Summary Of Significant Accounting Policies [Line Items]
Debt discount		$ 1,600,000	$ 1,600,000		1,600,000			92,000.0
Amortization of discount on convertible notes					$ 1,600,000			$ 0
Series B Convertible Preferred Stock
Summary Of Significant Accounting Policies [Line Items]
Preferred Stock Shares authorized to be issued \| shares		400,000	400,000		400,000			400,000
Common stock options and warrants to purchase \| shares		92,100	92,100		92,100			92,100
Common shares issued upon conversion of preferred stock \| shares					921,000
Maximum
Summary Of Significant Accounting Policies [Line Items]
Stockholders equity note stock split conversion ratio	0.067
Preferred Stock Shares authorized to be issued \| shares		5,000,000	5,000,000		5,000,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Stockholders equity note stock split conversion ratio	0.500