v3.26.1

Stock-Based Compensation - Non-options (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended		12 Months Ended
	Nov. 04, 2025	Apr. 08, 2025	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Weighted average price
Share-based compensation costs			$ 435	$ 180
BTI RSU
Number of shares
Outstanding, beginning balance (in shares)			107,000
Granted (in shares)		66,000	409,000
Vested (in shares)			(1,000)
Cancelled (in shares)			(3,000)
Outstanding, ending balance (in shares)			512,000		107,000
Weighted average price
Vesting period		1 year
Unrecognized stock-based compensation expense			$ 597	537
Fair value, non-option			$ 1
BTI RSU \| RSU vesting 100% at one year anniversary
Number of shares
Granted (in shares)			409,000
Weighted average price
Granted, Weighted average price (in dollars per share)			$ 1.86
BTI RSU \| RSU vesting 25% at one year and remaining in 12 quarters
Weighted average price
Vesting period			4 years
Vesting (as a percent)			25.00%
BTI RSU \| Nonemployee consultant
Weighted average price
Vesting period	2 years
OnkosXcel PSU
Number of shares
Outstanding, beginning balance (in shares)			1,072
Granted (in shares)			0		15
Cancelled (in shares)			0
Forfeited (in shares)			0
Outstanding, ending balance (in shares)			1,072		1,072
Vested aggregate (in shares)			1,037
Weighted average price
Outstanding, Weighted average price beginning balance (in dollars per share)			$ 5,663
Granted, Weighted average price (in dollars per share)			0
Cancelled, Weighted average price (in dollars per share)			0
Forfeited, Weighted average price (in dollars per share)			0
Vested, Weighted average price (in dollars per share)			$ 5,605
Outstanding, Weighted average price ending balance (in dollars per share)					$ 5,663
Vesting period			48 months
Unrecognized stock-based compensation expense			$ 58	319
OnkosXcel RSUs
Number of shares
Outstanding, beginning balance (in shares)			135
Granted (in shares)			0
Vested (in shares)			(2)
Cancelled (in shares)			0
Outstanding, ending balance (in shares)			133		135
Weighted average price
Unrecognized stock-based compensation expense			$ 12	$ 420

The number of equity-based payment instruments, excluding stock (or unit) options, that were cancelled during the reporting period.

+ References

No definition available.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a cancelled event.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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BioXcel Therapeutics, Inc. 10-Q