Line of Credit Facility, Letter of Credit Sub-Limit

No definition available.

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Namespace Prefix:	fslr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Total debt principal

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of debt and lease obligation, classified as current.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Period Type:	instant

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Description of the type of currency in which the debt instrument is required to be repaid.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
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Balance Type:	na
Period Type:	duration

- Definition

Description of reference rate used for variable rate of debt instrument.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtLongtermAndShorttermCombinedAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 9
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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9. Debt (Details) $ in Thousands, ₨ in Billions	1 Months Ended	6 Months Ended
9. Debt (Details) $ in Thousands, ₨ in Billions	Feb. 28, 2026 USD ($)	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2025 INR (₨)	Jan. 31, 2025 USD ($)	Jan. 31, 2025 INR (₨)	Feb. 29, 2024 USD ($)	Feb. 29, 2024 INR (₨)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 INR (₨)	Jun. 30, 2023 USD ($)	Jul. 31, 2022 USD ($)
Debt
Total debt principal		$ 37,635	$ 498,790
Less: unamortized issuance costs		0	(218)
Total debt		37,635	498,572
Current portion of debt		37,635	215,979
Noncurrent portion of debt		$ 0	282,593
Revolving Credit Facility
Debt
Debt instrument, currency		USD
Revolving credit facility		$ 0	0
Line of Credit Facility, Current Borrowing Capacity	$ 1,500,000										$ 1,000,000
Line of Credit Facility, Letter of Credit Sub-Limit	450,000	$ 150,000
Line of Credit Facility, Capacity Committed and Available	$ 150,000
Debt Instrument, Description of Variable Rate Basis	Borrowings under the Credit Facility bear interest at a rate per annum equal to, at our option, (i) the Term Secured Overnight Financing Rate (“Term SOFR”), plus a margin that ranges between 1.00% to 1.75% or (ii) an alternate base rate as defined in the credit agreement, plus a margin that ranges from 0.00% to 0.75%.
Revolving Credit Facility \| Minimum [Member]
Debt
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.10%
Revolving Credit Facility \| Maximum [Member]
Debt
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.225%
India Credit Facility
Debt
Debt instrument, currency		USD
Long-term debt, gross		$ 0	373,651
India Credit Facility \| DFC \| FS India Solar Ventures Private Limited
Debt
Line of Credit Facility, Current Borrowing Capacity												$ 500,000
India JPM Working Capital Facility
Debt
Debt instrument, currency		INR
Short-term debt		$ 19,612	26,140
India JPM Working Capital Facility \| JPMorgan Chase Bank, N.A. \| FS India Solar Ventures Private Limited
Debt
Line of Credit Facility, Current Borrowing Capacity									$ 66,000	₨ 6.2
India Citibank Working Capital Facility
Debt
Debt instrument, currency		INR
Short-term debt		$ 12,722	11,123
India Citibank Working Capital Facility \| Citibank, N.A. \| FS India Solar Ventures Private Limited
Debt
Line of Credit Facility, Current Borrowing Capacity					$ 67,800	₨ 6.4
India Credit Agricole Working Capital Facility
Debt
Debt instrument, currency		INR
Short-term debt		$ 5,301	41,157
India Credit Agricole Working Capital Facility \| Credit Agricole Corporate and Investment Bank \| FS India Solar Ventures Private Limited
Debt
Line of Credit Facility, Current Borrowing Capacity			90,100	₨ 8.5
India HSBC Working Capital Facility
Debt
Debt instrument, currency		INR
Short-term debt		$ 0	$ 46,719
India HSBC Working Capital Facility \| Hong Kong and Shanghai Banking Corporation Limited \| FS India Solar Ventures Private Limited
Debt
Line of Credit Facility, Current Borrowing Capacity							$ 86,900	₨ 8.2