v2.4.1.9

Fair Value Measurements - Assets measured (Details) (USD $) In Millions, unless otherwise specified | Dec. 04, 2014 | Aug. 28, 2014
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Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Short-term investments | $ 466 us-gaap_AvailableForSaleSecuritiesCurrent | $ 384 us-gaap_AvailableForSaleSecuritiesCurrent
Long-term marketable investments | 1,077 us-gaap_AvailableForSaleSecuritiesNoncurrent | 819 us-gaap_AvailableForSaleSecuritiesNoncurrent
Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 1,433 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1,705 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 466 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 384 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 1,077 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 819 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Restricted cash | 24 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 27 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Total assets measured at fair value on a recurring basis | 3,000 us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 2,935 us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Money market funds [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 866 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_MoneyMarketFundsMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1,281 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_MoneyMarketFundsMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Certificates of deposit [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 528 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 402 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 24 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 8 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 5 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Restricted cash | 24 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 27 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Government securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 31 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 136 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 136 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 273 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 284 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Commercial paper [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 7 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 22 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Corporate bonds [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 1 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 217 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 154 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 581 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 407 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Commercial Paper, Not Included with Cash and Cash Equivalents [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Short-term investments | 86 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperNotIncludedWithCashAndCashEquivalentsMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 85 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperNotIncludedWithCashAndCashEquivalentsMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Asset-backed securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Short-term investments | 3 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 217 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 127 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Marketable equity securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Long-term marketable investments | 1 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_EquitySecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_EquitySecuritiesMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 866 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1,281 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 1 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Restricted cash | 0 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Total assets measured at fair value on a recurring basis | 867 us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1,282 us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Money market funds [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 866 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_MoneyMarketFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1,281 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_MoneyMarketFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Certificates of deposit [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Restricted cash | 0 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Government securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Commercial paper [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Corporate bonds [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Commercial Paper, Not Included with Cash and Cash Equivalents [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Short-term investments | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperNotIncludedWithCashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperNotIncludedWithCashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Asset-backed securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Short-term investments | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 1 [Member] | Marketable equity securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Long-term marketable investments | 1 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_EquitySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_EquitySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 567 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 424 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 466 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 384 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 1,076 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 818 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Restricted cash | 24 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 27 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Total assets measured at fair value on a recurring basis | 2,133 us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1,653 us-gaap_AssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Money market funds [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_MoneyMarketFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_MoneyMarketFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Certificates of deposit [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 528 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 402 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 24 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 8 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 5 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Restricted cash | 24 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 27 us-gaap_RestrictedCashAndCashEquivalents / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Government securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 31 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 136 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 136 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 273 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 284 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_SovereignDebtMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Commercial paper [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 7 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 22 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Corporate bonds [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Cash equivalents | 1 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Short-term investments | 217 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 154 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 581 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 407 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Commercial Paper, Not Included with Cash and Cash Equivalents [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Short-term investments | 86 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperNotIncludedWithCashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 85 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_CommercialPaperNotIncludedWithCashAndCashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Asset-backed securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Short-term investments | 3 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 1 us-gaap_AvailableForSaleSecuritiesCurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Long-term marketable investments | 217 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | 127 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember
Level 2 [Member] | Marketable equity securities [Member] | Fair Value, Measurements, Recurring [Member] |  |
Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] |  |
Long-term marketable investments | $ 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_EquitySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | $ 0 us-gaap_AvailableForSaleSecuritiesNoncurrent / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_EquitySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 + Details
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- Definition Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 + Details
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 + Details
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- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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