UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 193,579	$ 250,280
Restricted cash	3,079	0
Accounts receivable, net of allowance for credit losses of $7,271 and $1,676, respectively	266,739	123,418
Loans and notes receivable from related parties, net of allowance for credit losses of $3,219 and $2,513, respectively	$ 198	$ 473
Financing Receivable, after Allowance for Credit Loss, Current, Related Party [Extensible Enumeration]	Related Party	Related Party
Investments in held-to-maturity debt securities, current	$ 378	$ 8,179
Prepaid expenses and other current assets	35,781	29,688
Total current assets	499,754	412,038
Loans and notes receivable from related parties, net of allowance for credit losses of $3,623 and $8,222, respectively	1,075	440
Property and equipment, net	43,561	35,695
Operating lease right-of-use assets	80,887	82,104
Intangible assets, net	11,272	2,543
Deferred tax assets	85,020	0
Goodwill	35,468	30,078
Other assets	1,711	2,242
Total assets	758,748	565,140
Current liabilities:
Accounts payable and other accrued expenses	14,228	11,998
Accrued payroll and benefits	61,718	46,332
Deferred revenue	15,601	12,522
Distributions payable to related parties	0	52,745
Operating lease liabilities, current	15,445	3,958
Notes payable to related parties, current portion	$ 54,826	$ 62,340
Notes Payable, Current, Related Party [Extensible Enumeration]	Related Party	Related Party
Other current liabilities	$ 36,479	$ 5,912
Total current liabilities	198,297	195,807
Operating lease liabilities, noncurrent	102,939	106,448
Notes payable to related parties, less current portion	$ 232,887	$ 287,745
Notes Payable, Noncurrent, Related Party [Extensible Enumeration]	Related Party	Related Party
Tax Receivable Agreement liability	$ 74,363	$ 0
Other liabilities	11,195	3,517
Total liabilities	619,681	593,517
Commitments and contingencies (Note 15)
Redeemable noncontrolling interest (Note 10)	0	106,354
Stockholders' equity (deficit):
Preferred stock, par value $0.0001 per share: 100,000,000 shares authorized, no shares issued and outstanding as of September 30, 2026 and December 31, 2025	0	0
Additional paid-in-capital	71,006	0
Accumulated deficit	(790,490)	(134,742)
Accumulated other comprehensive income	(21)	0
Total stockholders' deficit attributable to Andersen Group Inc.	(719,494)	(134,731)
Noncontrolling interest (Note 10)	858,561	0
Total stockholders' equity (deficit)	139,067	(134,731)
Total liabilities, redeemable noncontrolling interest and stockholders' equity (deficit)	758,748	565,140
Class A Common Stock
Stockholders' equity (deficit):
Common stock, value	2	1
Class B Common Stock
Stockholders' equity (deficit):
Common stock, value	$ 9	$ 10