EARNINGS PER SHARE - Schedule of Discontinuing Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Numerator
Net (loss) income	$ (217)	$ 19,421	$ (355)	$ 18,185
Less: Net (loss) income attributable to non-controlling interest	$ (79)	$ 6,129	$ (125)	$ 5,865
Weighted average shares of Class A common stock outstanding - basic (in shares)	19,419,792	24,345,826	21,638,108	23,909,714
Basic net (loss) income per share (in USD per share)	$ (0.01)	$ 0.55	$ (0.01)	$ 0.52
Diluted net (loss) income per share:
Reallocation of net (loss) income assuming conversion of common units	$ 0	$ 4,214	$ 0	$ 5,716
Weighted average shares of Class A common stock outstanding - basic (in shares)	19,419,792	24,345,826	21,638,108	23,909,714
Weighted average effect of dilutive securities (in shares)	123,819	9,590,295	647,521	10,273,553
Weighted average shares of Class A common stock outstanding - diluted (in shares)	19,543,611	33,936,121	22,285,629	34,183,267
Diluted net (loss) income per share (in USD per share)	$ (0.01)	$ 0.55	$ (0.01)	$ 0.49
Class B Common Stock
Diluted net (loss) income per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	8,381,681		8,381,681
Out-of-the-money Options
Diluted net (loss) income per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	6,911,778	4,362,416	4,601,639	4,436,416
Discontinued Operations \| Class A Common Stock
Numerator
Net (loss) income	$ (217)	$ 19,421	$ (355)	$ 18,185
Less: Net (loss) income attributable to non-controlling interest	(79)	6,129	(125)	5,865
Net (loss) income attributable to Class A common stockholders	$ (138)	$ 13,292	$ (230)	$ 12,320
Weighted average shares of Class A common stock outstanding - basic (in shares)	19,419,792	24,345,826	21,638,108	23,909,714
Basic net (loss) income per share (in USD per share)	$ (0.01)	$ 0.55	$ (0.01)	$ 0.52
Diluted net (loss) income per share:
Net (loss) income attributable to Class A common stockholders	$ (138)	$ 13,292	$ (230)	$ 12,320
Reallocation of net (loss) income assuming conversion of common units	(60)		(95)	4,459
Net (loss) income attributable to Class A common stockholders – diluted	$ (198)		$ (325)	$ 16,779
Weighted average shares of Class A common stock outstanding - basic (in shares)	19,419,792	24,345,826	21,638,108	23,909,714
Weighted average effect of dilutive securities (in shares)	8,381,681		8,381,681	10,273,553
Weighted average shares of Class A common stock outstanding - diluted (in shares)	27,801,473	24,345,826	30,019,789	34,183,267
Diluted net (loss) income per share (in USD per share)	$ (0.01)		$ (0.01)	$ 0.49
Discontinued Operations \| Class B Common Stock
Diluted net (loss) income per share:
Antidilutive securities excluded from computation of earnings per share (in shares)		8,637,499
Discontinued Operations \| Out-of-the-money Options
Diluted net (loss) income per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	6,911,778	4,362,416	4,601,639	4,436,416
Discontinued Operations \| Employee Stock Options And Restricted Stock Units (RSUs)
Diluted net (loss) income per share:
Antidilutive securities excluded from computation of earnings per share (in shares)	123,819	952,796	647,521

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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