Number of warrants or rights outstanding, number of conversion.

No definition available.

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Namespace Prefix:	ktra_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_ClassOfWarrantOrRightOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares of common stock issued as dividends during the period. Excludes stock splits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Stockholders' Equity - Schedule of Outstanding Series C Agent Warrants (Detail) - $ / shares	12 Months Ended
	Jun. 30, 2022	Apr. 14, 2022	Jun. 30, 2021
Warrants exercise price		$ 0.001
Series C Warrants
Number	2,444,000		2,444,000
Number of conversion shares (in thousands)	2,100,000
Cumulative common stock dividends (in thousands)	1,470,000
Series C Warrants \| Series 1 Warrants Outstanding
Number	1,929,000
Warrants exercise price	$ 1.16
Number of conversion shares (in thousands)	1,663,000
Cumulative common stock dividends (in thousands)	1,164,000
Series C Warrants \| Series 2 Warrants Outstanding Member
Number	219,000
Warrants exercise price	$ 1.21
Number of conversion shares (in thousands)	180,000
Cumulative common stock dividends (in thousands)	126,000
Series C Warrants \| Series 3 Warrants Outstanding
Number	296,000
Warrants exercise price	$ 1.15
Number of conversion shares (in thousands)	257,000
Cumulative common stock dividends (in thousands)	180,000