XML 86 R38.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Cash and Investments in Marketable Securities - Additional Information (Detail) (USD $) | 12 Months Ended | 1 Months Ended |
--- | --- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Jul. 31, 2012 | Jul. 11, 2012
Cash and Investments in Marketable Securities [Line Items] |  |  |  |  |
Maximum maturity term for debt securities investment | Two years or less |  |  |  |
Weighted average maturity term for debt securities investment | One year or less |  |  |  |
Available-for-sale securities, sold | $ 21,700,000 us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds | $ 2,900,000 us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds | $ 5,400,000 us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds |  |
Restricted cash | 25,000,000 us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue |  |  |  |
Level 1 to level 2 transfers | 0 us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount | 0 us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount |  |  |
Level 2 to level 1 transfers | 0 us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount | 0 us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount |  |  |
Letter of credit | 2,400,000 nktr_LettersOfCreditOutstanding | 2,400,000 nktr_LettersOfCreditOutstanding |  |  |
12% Senior Secured Notes Due July 2017 [Member] |  |  |  |  |
Cash and Investments in Marketable Securities [Line Items] |  |  |  |  |
Restricted cash | $ 25,000,000 us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |
Senior secured notes, interest rate | 12.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  | 12.00%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember
Senior secured notes, maturity date | Jul. 15, 2017 |  |  | Jul. 15, 2017 |

X
- Details
Name: | nktr_CashAndInvestmentsInMarketableSecuritiesLineItems
Namespace Prefix: | nktr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Debt instrument maximum maturity period. + References No definition available. + Details
Name: | nktr_DebtInstrumentMaximumMaturityPeriod
Namespace Prefix: | nktr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Debt Instrument Weighted Average Maturity Period One + References No definition available. + Details
Name: | nktr_DebtInstrumentWeightedAverageMaturityPeriodOne
Namespace Prefix: | nktr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Letters Of Credit Outstanding + References No definition available. + Details
Name: | nktr_LettersOfCreditOutstanding
Namespace Prefix: | nktr_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceeds
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -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 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentMaturityDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. + 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 (bb) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1. + 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 (bb) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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 short-term 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. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations. + 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
Name: | us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |