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) - USD ($)	3 Months Ended				6 Months Ended	9 Months Ended		12 Months Ended
	Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	Feb. 28, 2018	Nov. 30, 2018	Feb. 28, 2019	Feb. 28, 2018	May 31, 2019	May 31, 2018	Dec. 31, 2017	Nov. 08, 2018	Jun. 07, 2018	Aug. 24, 2017	Aug. 23, 2017	Apr. 30, 2010
Summary Of Significant Accounting Policies [Line Items]
Net loss	$ (12,573,811)	$ (14,305,381)	$ (14,413,569)	$ (17,950,100)		$ (41,292,761)	$ (40,526,058)
Accumulated (deficit)	(214,432,156)					(214,432,156)			$ (173,139,396)
Balance in excess of federally insured limits	1,300,000					1,300,000			$ 1,100,000
Impairment charges						0	0
Pre-launch inventory qualified for capitalization	$ 0					$ 0
Estimated future unvested forfeitures					0.00%
Common stock, shares authorized	600,000,000					600,000,000			375,000,000			450,000,000	375,000,000	350,000,000	100,000,000
Treasury stock, par value									$ 0.001
Treasury stock, shares									159,011
Amortization of discount on convertible notes	$ 559,383			493,022		$ 676,917	1,666,017
Amortization of debt issuance costs						$ 676,917	435,609
Federal statutory income tax rate, percent						21.00%				35.00%
Effective income tax rate reconciliation, at blended income tax rate, percent						28.62%
Tax cuts and jobs act of 2017, incomplete accounting, change in tax rate, deferred tax liability, provisional income tax benefit									$ 17,497,051
Deferred income tax benefit						$ (2,826,919)	$ 0
Derivative Liability	2,826,919					$ 2,826,919
Common stock options and warrants to purchase						175,043,638	130,457,331
Interest Expense	1,050,413			$ 3,069,189		$ 2,955,386	$ 5,531,238
Convertible Notes Payable [Member]
Summary Of Significant Accounting Policies [Line Items]
Interest Expense	100,000					600,000
Scenario, Forecast [Member] \| Prostagene Llc [Member]
Summary Of Significant Accounting Policies [Line Items]
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent								21.00%
Equity Securities
Summary Of Significant Accounting Policies [Line Items]
Deferred offering costs	3,300,000					3,300,000			3,500,000
Short-Term Convertible Notes
Summary Of Significant Accounting Policies [Line Items]
Debt discount	0					0			0
Direct costs associated with the convertible notes						1,000,000			400,000
Amortization of debt issuance costs						200,000	400,000
Short-Term Convertible Notes \| Detachable Common Stock Warrants
Summary Of Significant Accounting Policies [Line Items]
Debt discount	$ 4,200,000					4,200,000			$ 1,500,000
Amortization of discount on convertible notes						$ 700,000	$ 1,600,000
Series B Convertible Preferred Stock
Summary Of Significant Accounting Policies [Line Items]
Preferred Stock Shares authorized to be issued	400,000					400,000			400,000
Common stock options and warrants to purchase	92,100					92,100			92,100
Common shares issued upon conversion of preferred stock						921,000
Maximum
Summary Of Significant Accounting Policies [Line Items]
Common stock, shares authorized											600,000,000
Preferred Stock Shares authorized to be issued	5,000,000					5,000,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Common stock, shares authorized											450,000,000