EARNINGS PER SHARE - Discontinuing Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Numerator
Net loss	$ 0	$ (1,554)	$ (138)	$ (1,236)
Less: Net loss attributable to non-controlling interest	$ 0	$ (381)	$ (46)	$ (264)
Weighted average shares of Class A common stock outstanding - basic (in shares)	21,798,840	23,834,233	22,747,267	23,691,648
Basic net (loss) income per share (in USD per share)	$ 0	$ (0.05)	$ 0.00	$ (0.04)
Diluted net loss per share:
Reallocation of net loss assuming conversion of common units	$ 557		$ 0	$ 0
Weighted average shares of Class A common stock outstanding - basic (in shares)	21,798,840	23,834,233	22,747,267	23,691,648
Weighted average effect of dilutive securities (in shares)	8,783,747		909,373	389,584
Weighted average shares of Class A common stock outstanding - diluted (in shares)	30,582,587		23,656,640	24,081,232
Diluted net (loss) income per share (in USD per share)	$ 0	$ (0.05)	$ 0.00	$ (0.04)
Class B Common Stock
Diluted net loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)		9,408,427	8,381,681	9,720,698
Out-of-the-money Options
Diluted net loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	4,812,850	4,227,718	3,381,943	4,660,034
Employee Stock Options And Restricted Stock Units (RSUs)
Diluted net loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)		299,505
Discontinued Operations \| Class A Common Stock
Numerator
Net loss		$ (1,554)	$ (138)	$ (1,236)
Less: Net loss attributable to non-controlling interest		(381)	(46)	(264)
Net loss attributable to Class A common stockholders		$ (1,173)	$ (92)	$ (972)
Weighted average shares of Class A common stock outstanding - basic (in shares)		23,834,233	22,747,267	23,691,648
Basic net (loss) income per share (in USD per share)		$ (0.05)	$ 0.00	$ (0.04)
Diluted net loss per share:
Net loss attributable to Class A common stockholders		$ (1,173)	$ (92)	$ (972)
Reallocation of net loss assuming conversion of common units		0	(35)	0
Net loss attributable to Class A common stockholders – diluted		$ (1,173)	$ (127)	$ (972)
Weighted average shares of Class A common stock outstanding - basic (in shares)		23,834,233	22,747,267	23,691,648
Weighted average effect of dilutive securities (in shares)		0	8,381,681	0
Weighted average shares of Class A common stock outstanding - diluted (in shares)		23,834,233	31,128,948	23,691,648
Diluted net (loss) income per share (in USD per share)		$ (0.05)	$ 0.00	$ (0.04)
Discontinued Operations \| Class B Common Stock
Diluted net loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)		9,408,427		9,720,698
Discontinued Operations \| Out-of-the-money Options
Diluted net loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)		4,227,718	3,381,943	4,660,034
Discontinued Operations \| Employee Stock Options And Restricted Stock Units (RSUs)
Diluted net loss per share:
Antidilutive securities excluded from computation of earnings per share (in shares)		299,505	909,373	389,584

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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