Change in fair value of warrant liability.

No definition available.

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Namespace Prefix:	nept_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Class of warrant or right number of warrants issued.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Initial warrant liability.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Residual amount allocated.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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-Topic 210
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-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Section S99
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Expiration date of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Details

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Liability Related to Warrants - Additional Information (Details) - USD ($)					12 Months Ended
	Mar. 30, 2022	Mar. 14, 2022	Feb. 19, 2021	Oct. 22, 2020	Mar. 31, 2022	Mar. 31, 2021
Class Of Warrant Or Right [Line Items]
Number of warrants issued					1,428,574	497,355
Proceeds from the issuance of shares and warrants		$ 8,000,000.0
Exercise price of warrants					$ 28.64
Warrant liability					$ 5,570,530	$ 10,462,137
Change in fair value of warrant liability					(1,572,299)
Common Shares
Class Of Warrant Or Right [Line Items]
Shares issued during period, shares		528,572
Number of shares exercisable for common share		1
Residual amount allocated					306,868
Prefunded Warrants
Class Of Warrant Or Right [Line Items]
Number of warrants issued		185,715
Exercise price of warrants		$ 0.0035
Residual amount allocated					$ 107,818
Gross proceeds from offering	$ 650
Series A Warrants
Class Of Warrant Or Right [Line Items]
Class of warrant or right, number of securities called by warrants or rights		714,286
Combined offering price		$ 20
Exercise price of warrants		$ 11.20			$ 11.20
Warrant liability					$ 3,270,816
Change in fair value of warrant liability					$ (1,572,299)
Warrants expiring date					Sep. 14, 2027
Series A Warrants \| Common Shares \| Maximum
Class Of Warrant Or Right [Line Items]
Stock issued during period, shares, conversion of units		714,286
Series A Warrants \| Black-Scholes Model
Class Of Warrant Or Right [Line Items]
Initial warrant liability					$ 4,757,559
Series B Warrants
Class Of Warrant Or Right [Line Items]
Class of warrant or right, number of securities called by warrants or rights		714,286
Combined offering price		$ 20
Exercise price of warrants		$ 11.20			$ 11.20
Warrant liability					$ 1,683,241
Change in fair value of warrant liability					$ (1,192,267)
Warrants expiring date					Mar. 14, 2028
Series B Warrants \| Common Shares \| Maximum
Class Of Warrant Or Right [Line Items]
Stock issued during period, shares, conversion of units		714,286
Series B Warrants \| Black-Scholes Model
Class Of Warrant Or Right [Line Items]
Initial warrant liability					$ 2,857,755
2020 Warrants
Class Of Warrant Or Right [Line Items]
Number of warrants issued				300,926
Exercise price of warrants				$ 78.75	$ 78.75
Warrant liability				$ 11,831,000	$ 309,769	6,174,137
Residual amount allocated				$ 23,169,000
Change in fair value of warrant liability					$ (5,877,802)	(5,893,160)
Warrants expiring date				Oct. 22, 2025	Oct. 22, 2025
2021 Warrants
Class Of Warrant Or Right [Line Items]
Number of warrants issued			196,429
Exercise price of warrants			$ 78.75		$ 78.75
Warrant liability			$ 6,288,998		$ 306,704	4,288,000
Residual amount allocated			$ 48,711,002
Change in fair value of warrant liability					$ (3,990,948)	$ (1,976,093)
Warrants expiring date			Aug. 19, 2026		Aug. 19, 2026