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Interim Financial Statements - Narrative (Details) $ in Thousands, ₩ in Billions	6 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jul. 28, 2026 USD ($)	Jul. 28, 2026 KRW (₩)	Dec. 31, 2025 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Long-term finance lease liabilities	$ 87,500				$ 105,000
Unbilled receivables	309,100				294,100
Contract liabilities	393,000				390,800
Deferred revenue and customer advances	93,124				$ 69,611
Revenue recognized	27,800	$ 36,600
Letters of Credit Issued for Customer Advance Payments Received
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Customer advance payments received	100,000
Subsequent Event \| Letters of Credit Issued for Customer Advance Payments Received
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Customer advance payments received			$ 100,000
Foreign Direct Investment Cash Support Agreement \| Subsequent Event
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Potential cash grants			$ 100,000	₩ 150
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 284,600
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-07-01 \| Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-07-01 \| Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected timing of satisfaction, period	5 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected timing of satisfaction, period
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 15,300
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-07-01 \| Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected timing of satisfaction, period	5 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-07-01 \| Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected timing of satisfaction, period	10 years