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3/31/2011
USD ($)
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{fslr_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis} : Fair Value, Inputs, Level 1 [Member]
3/31/2011
USD ($)
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{fslr_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis} : Fair Value, Inputs, Level 1 [Member]
12/31/2010
USD ($)
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{fslr_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisDisclosureItemsAxis} : Fair Value, Inputs, Level 1 [Member]
3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Foreign Agency Debt [Member]
3/31/2011
USD ($)
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12/31/2010
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Supranational Debt [Member]
3/31/2011
USD ($)
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12/31/2010
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Certificates of Deposit [Member]
3/31/2011
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : US Government Agencies Debt Securities [Member]
3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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USD ($)
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USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Supranational Debt [Member]
3/31/2011
USD ($)
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12/31/2010
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : Certificates of Deposit [Member]
3/31/2011
USD ($)
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{us-gaap_ScheduleOfAvailableForSaleSecuritiesMajorTypesOfDebtAndEquitySecuritiesAxis} : US Government Agencies Debt Securities [Member]
3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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USD ($)
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USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
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12/31/2010
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3/31/2011
USD ($)
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12/31/2010
USD ($)
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3/31/2011
USD ($)
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3/31/2011
USD ($)
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