Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues:
Total revenues	$ 69,821	$ 69,383	$ 128,056
Transaction-based expenses:
Transaction-based expenses	(431)	(483)	(3,034)
Total revenues, less transaction-based expenses	69,390	68,900	125,022
Operating expenses:
Compensation and benefits	106,593	145,514	94,654
Professional services	11,905	14,265	12,450
Acquisition-related transaction costs	0	5,113	882
Advertising and market development	3,486	4,754	5,090
Rent and occupancy	4,884	5,455	3,744
Technology and communications	14,507	11,489	8,243
General and administrative	12,510	11,324	4,358
Depreciation and amortization	6,954	6,026	5,390
Total operating expenses	160,839	203,940	134,811
Operating loss	(91,449)	(135,040)	(9,789)
Interest and other income (expenses):
Interest income (expenses), net	6,421	2,681	(2,307)
(Loss) gain from change in fair value of warrant liabilities	(6,465)	19,836	(6,064)
Other income, net	763	945	47
Total interest and other income (expenses)	719	23,462	(8,324)
Loss before provision for income taxes	(90,730)	(111,578)	(18,113)
Provision for income taxes	819	327	386
Net loss	(91,549)	(111,905)	(18,499)
Net loss attributable to noncontrolling interest	(1,328)	(46)	0
Net loss attributable to Forge Global Holdings, Inc.	$ (90,221)	$ (111,859)	$ (18,499)
Earnings Per Share [Abstract]
Basic (in dollars per share)	$ (0.52)	$ (0.78)	$ (0.34)
Diluted (in dollars per share)	$ (0.52)	$ (0.80)	$ (0.34)
Weighted-average shares used in computing net loss per share attributable to Forge Global Holdings, Inc. common stockholders:
Basic (in shares)	173,402,167	143,839,981	54,295,304
Diluted (in shares)	173,402,167	145,013,346	54,295,304
Marketplace revenue
Revenues:
Total revenues	$ 25,790	$ 40,665	$ 107,723
Custodial administration fees
Revenues:
Total revenues	$ 44,031	$ 28,718	$ 20,333