INCOME TAXES - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Deferred tax assets:
Net operating losses	$ 129,985	$ 90,330
Tax credits	29,707	22,046
Stock-based compensation	3,847	2,046
Lease liabilities	5,271	8,294
Reserves	0	379
Capitalized research and development expenses	127,402	90,202
Accruals and other temporary differences	4,575	3,000
Total deferred tax assets	300,787	216,297
Valuation allowance	(279,370)	(191,734)	$ (120,116)
Total deferred tax assets, net of valuation allowance	21,417	24,563
Deferred tax liabilities:
Depreciation	(17,106)	(16,904)
Right-of-use asset	(4,366)	(7,476)
Total deferred tax liabilities	(21,472)	(24,380)
Net deferred tax (liabilities) assets	$ (55)
Net deferred tax (liabilities) assets		$ 183