Consolidated Statements of Equity (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Offering costs	$ 0.2		$ 3.6
Offering costs, at market	$ 2.0	$ 2.0	$ 1.1

Specific incremental costs directly attributable to a At-the-Market offering of securities which are deferred at the end of the reporting period.

No definition available.

Name:	tgtx_OfferingCostsAtMarket
Namespace Prefix:	tgtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant