LOANS PAYABLE (Details) $ in Thousands		9 Months Ended
Feb. 28, 2019 USD ($) loan	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
Payment of loan payable		$ (14,590)
Prime Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rate ( as a percent)	4.75%
Prime Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rate ( as a percent)	10.25%
Term Loan [Member]
Debt Instrument [Line Items]
Maximum term loan facility	$ 60,000
Amount drawn on first advance	30,000
Additional advances not drawn	30,000
Minimum amount raised from unrestricted cash proceeds	150,000
Expected prepayment on outstanding advances	$ 5,000
Prepayment charge (as a percent)	3.50%
Payment of loan payable		14,600
Interest on past due outstanding (as a percent)	4.00%
Term Loan [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Amount of monthly principal payments		2,500
Term Loan [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Number of advances \| loan	4
Amount of monthly principal payments		$ 2,700
Term Loan [Member] \| Within First twelve Months Of Closing Date [Member]
Debt Instrument [Line Items]
Prepayment charge (as a percent)	3.00%
Term Loan [Member] \| After Twelve Months But On Or Before Twenty Four Months [Member]
Debt Instrument [Line Items]
Prepayment charge (as a percent)	1.50%
Term Loan [Member] \| After Twenty Four Months Of Closing Date [Member]
Debt Instrument [Line Items]
Prepayment charge (as a percent)	0.00%

Amount of additional advances for each draw.

No definition available.

Name:	tgtx_AdditionalAdvancesForEachDraw
Namespace Prefix:	tgtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount drawn on first advance.

+ References

No definition available.

+ Details

Name:	tgtx_DebtInstrumentFirstAdvanceDrawn
Namespace Prefix:	tgtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Minimum amount raised from unrestricted cash proceeds.

+ References

No definition available.

+ Details

Name:	tgtx_MinimumAmountRaisedFromUnrestrictedCashProceeds
Namespace Prefix:	tgtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Minimum amount of expected prepayment of debt.

+ References

No definition available.

+ Details

Name:	tgtx_MinimumExpectedPrepaymentOfDebt
Namespace Prefix:	tgtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of advances.

+ References

No definition available.

+ Details

Name:	tgtx_NumberOfAdvances
Namespace Prefix:	tgtx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of Interest On Past Due Outstanding.

+ References

No definition available.

+ Details

Name:	tgtx_PercentageOfInterestOnPastDueOutstanding
Namespace Prefix:	tgtx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of prepayment charge.

+ References

No definition available.

+ Details

Name:	tgtx_PercentageOfPrepaymentCharge
Namespace Prefix:	tgtx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ 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
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentPeriodicPaymentPrincipal
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow (outflow) from long-term debt wholly or partially secured by collateral. Excludes tax exempt secured debt.

+ References

No definition available.

+ Details

Name:	us-gaap_ProceedsFromRepaymentsOfSecuredDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
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Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentAxis=tgtx_TermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_ExtinguishmentOfDebtAxis=tgtx_WithinFirstTwelveMonthsOfClosingDateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

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