Subsequent Events- Additional Information (Details) $ / shares in Units, $ in Thousands		3 Months Ended
	Mar. 05, 2025 USD ($) PerTonne Tonnes $ / shares	Mar. 31, 2025	Apr. 01, 2025 USD ($)
Subsequent Event [Line Items]
Debt Instrument, Description		The Notes will mature on April 1, 2030 and bear an initial conversion price of $3.78 per share, which represents a 43% premium to Lithium Americas’ 5-day VWAP on the New York Stock Exchange ended on March 5, 2025. The Company will initially pay interest on the Notes in-kind or in cash at a rate of 9.875% per annum until the maturity of the Notes. Under the terms of the PPA, Orion will receive fixed payments of $128 per tonne ($152 per tonne assuming draw of the Delayed Draw Notes) of the total lithium produced each year at Thacker Pass for a period of 72 quarters after first production. Orion will receive additional variable payments of 0.96% of total gross revenue (1.14% of total gross revenue assuming draw of the Delayed Draw Notes) for the life of the mine. Both fixed and variable payments will only apply to the first 41,500 tonnes of lithium produced each year and are subject to certain adjustments relating to total Phase 1 project costs. The production payments are also subject to certain adjustments related to the tonnage of battery-grade lithium carbonate equivalent sold. The variable payments are also subject to certain adjustments related to the future price of lithium.
Maturity date	Apr. 01, 2030
Initial conversion price | $ / shares	$ 3.78
Percentage of premium of convertible notes	43.00%
Percentage rate of Notes in-kind or in cash	9.875%
Commited contribution			$ 191,600
General Motors Holdings LLC [Member]
Subsequent Event [Line Items]
Commited contribution			100,000
PPA [Member]
Subsequent Event [Line Items]
Fixed and variable payments recieved | Tonnes	41,500
Fixed payments received | PerTonne	128
Percentage of additional variable payments recieved on total gross revenue	0.96%
Delayed Draw Notes [Member] | PPA [Member]
Subsequent Event [Line Items]
Fixed payments received | PerTonne	152
Percentage of additional variable payments recieved on total gross revenue	1.14%
Orion Resource Partners LP (Orion) [Member]
Subsequent Event [Line Items]
Aggregate principal amount	$ 195,000
Long-Term debt, term	2 years
Orion Resource Partners LP (Orion) [Member] | Thacker Pass [Member]
Subsequent Event [Line Items]
Amount paid for exchange	$ 25,000
Additional commitment amount	30,000
Amount of initial investment	$ 220,000
Subsequents Events [Member]
Subsequent Event [Line Items]
Commited contribution			191,600
Subsequents Events [Member] | General Motors Holdings LLC [Member]
Subsequent Event [Line Items]
Commited contribution			100,000
Subsequents Events [Member] | Orion Resource Partners LP (Orion) [Member] | Phase 1 of Thacker Pass [Member]
Subsequent Event [Line Items]
Investments			$ 250,000