<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.22.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>907</ContextCount>
  <ElementCount>594</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>196</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>5</UnitCount>
  <MyReports>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001001 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DocumentandEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>0002002 - Document - Audit Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/AuditInformation</Role>
      <ShortName>Audit Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1001003 - Statement - Consolidated Statements of Financial Position</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ConsolidatedStatementsofFinancialPosition</Role>
      <ShortName>Consolidated Statements of Financial Position</ShortName>
      <MenuCategory>Uncategorized</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1002004 - Statement - Consolidated Statements of Financial Position (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ConsolidatedStatementsofFinancialPositionParenthetical</Role>
      <ShortName>Consolidated Statements of Financial Position (Parenthetical)</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1003005 - Statement - Consolidated Statements of Operations and Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ConsolidatedStatementsofOperationsandComprehensiveIncome</Role>
      <ShortName>Consolidated Statements of Operations and Comprehensive Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1004006 - Statement - Consolidated Statements of Stockholder???s Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ConsolidatedStatementsofStockholdersEquity</Role>
      <ShortName>Consolidated Statements of Stockholder???s Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1005007 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ConsolidatedStatementsofCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>2101101 - Disclosure - Business and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/BusinessandBasisofPresentation</Role>
      <ShortName>Business and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2102102 - Disclosure - Significant Accounting Policies and Pronouncements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/SignificantAccountingPoliciesandPronouncements</Role>
      <ShortName>Significant Accounting Policies and Pronouncements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2105103 - Disclosure - Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/Investments</Role>
      <ShortName>Investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2126104 - Disclosure - Derivative Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DerivativeInstruments</Role>
      <ShortName>Derivative Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2133105 - Disclosure - Fair Value of Assets and Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/FairValueofAssetsandLiabilities</Role>
      <ShortName>Fair Value of Assets and Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2139106 - Disclosure - Deferred Policy Acquisition Costs</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DeferredPolicyAcquisitionCosts</Role>
      <ShortName>Deferred Policy Acquisition Costs</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2143107 - Disclosure - Policyholders' Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/PolicyholdersLiabilities</Role>
      <ShortName>Policyholders' Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2148108 - Disclosure - Certain Long-Duration Contracts With Guarantees</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/CertainLongDurationContractsWithGuarantees</Role>
      <ShortName>Certain Long-Duration Contracts With Guarantees</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2154109 - Disclosure - Reinsurance</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/Reinsurance</Role>
      <ShortName>Reinsurance</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2161110 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2167111 - Disclosure - Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/Equity</Role>
      <ShortName>Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2172112 - Disclosure - Statutory Net Income and Surplus and Dividend Restrictions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/StatutoryNetIncomeandSurplusandDividendRestrictions</Role>
      <ShortName>Statutory Net Income and Surplus and Dividend Restrictions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2174113 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2179114 - Disclosure - Commitments and Contingent Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/CommitmentsandContingentLiabilities</Role>
      <ShortName>Commitments and Contingent Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2181115 - Disclosure - Schedule I - Summary of Investments Other Than investments in Related Parties</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ScheduleISummaryofInvestmentsOtherThaninvestmentsinRelatedParties</Role>
      <ShortName>Schedule I - Summary of Investments Other Than investments in Related Parties</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2203201 - Disclosure - Significant Accounting Policies and Pronouncements (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/SignificantAccountingPoliciesandPronouncementsPolicies</Role>
      <ShortName>Significant Accounting Policies and Pronouncements (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.prudential.com/role/SignificantAccountingPoliciesandPronouncements</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2306301 - Disclosure - Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsTables</Role>
      <ShortName>Investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/Investments</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2327302 - Disclosure - Derivative Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DerivativeInstrumentsTables</Role>
      <ShortName>Derivative Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/DerivativeInstruments</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2334303 - Disclosure - Fair Value of Assets and Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesTables</Role>
      <ShortName>Fair Value of Assets and Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/FairValueofAssetsandLiabilities</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2340304 - Disclosure - Deferred Policy Acquisition Costs (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DeferredPolicyAcquisitionCostsTables</Role>
      <ShortName>Deferred Policy Acquisition Costs (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/DeferredPolicyAcquisitionCosts</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2344305 - Disclosure - Policyholders' Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/PolicyholdersLiabilitiesTables</Role>
      <ShortName>Policyholders' Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/PolicyholdersLiabilities</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2349306 - Disclosure - Certain Long-Duration Contracts With Guarantees (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/CertainLongDurationContractsWithGuaranteesTables</Role>
      <ShortName>Certain Long-Duration Contracts With Guarantees (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/CertainLongDurationContractsWithGuarantees</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2355307 - Disclosure - Reinsurance (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ReinsuranceTables</Role>
      <ShortName>Reinsurance (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/Reinsurance</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2362308 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/IncomeTaxes</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2368309 - Disclosure - Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/EquityTables</Role>
      <ShortName>Equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/Equity</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2375310 - Disclosure - Related Party Transactions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/RelatedPartyTransactionsTables</Role>
      <ShortName>Related Party Transactions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.prudential.com/role/RelatedPartyTransactions</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2404401 - Disclosure - Significant Accounting Policies and Pronouncements (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/SignificantAccountingPoliciesandPronouncementsNarrativeDetails</Role>
      <ShortName>Significant Accounting Policies and Pronouncements (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/SignificantAccountingPoliciesandPronouncementsPolicies</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2407402 - Disclosure - Investments (Fixed Maturities Securities Excluding Investments Classified as Trading) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsFixedMaturitiesSecuritiesExcludingInvestmentsClassifiedasTradingDetails</Role>
      <ShortName>Investments (Fixed Maturities Securities Excluding Investments Classified as Trading) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2408403 - Disclosure - Investments (Fair Value and Losses by Investment Category and Length of Time in a Loss Position) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsFairValueandLossesbyInvestmentCategoryandLengthofTimeinaLossPositionDetails</Role>
      <ShortName>Investments (Fair Value and Losses by Investment Category and Length of Time in a Loss Position) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2409404 - Disclosure - Investments (Amortized Cost and Fair Value of Fixed Maturities by Contractual Maturities) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsAmortizedCostandFairValueofFixedMaturitiesbyContractualMaturitiesDetails</Role>
      <ShortName>Investments (Amortized Cost and Fair Value of Fixed Maturities by Contractual Maturities) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2410405 - Disclosure - Investments (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsNarrativeDetails</Role>
      <ShortName>Investments (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2411406 - Disclosure - Investments (Fixed Maturities Securities Proceeds) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsFixedMaturitiesSecuritiesProceedsDetails</Role>
      <ShortName>Investments (Fixed Maturities Securities Proceeds) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2412407 - Disclosure - Investments (Credit Losses Recognized In Earnings on Fixed Maturity Securities Held by the Company) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsCreditLossesRecognizedInEarningsonFixedMaturitySecuritiesHeldbytheCompanyDetails</Role>
      <ShortName>Investments (Credit Losses Recognized In Earnings on Fixed Maturity Securities Held by the Company) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2413408 - Disclosure - Investments (Commercial Mortgage and Other Loans) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsCommercialMortgageandOtherLoansDetails</Role>
      <ShortName>Investments (Commercial Mortgage and Other Loans) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2414409 - Disclosure - Investments (Allowance for Credit Losses) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsAllowanceforCreditLossesDetails</Role>
      <ShortName>Investments (Allowance for Credit Losses) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2415410 - Disclosure - Investments (Credit Quality Indicators) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsCreditQualityIndicatorsDetails</Role>
      <ShortName>Investments (Credit Quality Indicators) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2416411 - Disclosure - Investments (Analysis of Past Due Commercial Mortgage, Agricultural, and Other Loans) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsAnalysisofPastDueCommercialMortgageAgriculturalandOtherLoansDetails</Role>
      <ShortName>Investments (Analysis of Past Due Commercial Mortgage, Agricultural, and Other Loans) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2417412 - Disclosure - Investments (Other Invested Assets) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsOtherInvestedAssetsDetails</Role>
      <ShortName>Investments (Other Invested Assets) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2418413 - Disclosure - Investments (Equity Method Investments, Statement of Financial Position) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsEquityMethodInvestmentsStatementofFinancialPositionDetails</Role>
      <ShortName>Investments (Equity Method Investments, Statement of Financial Position) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2419414 - Disclosure - Investments (Equity Method Investments, Statement of Operations) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsEquityMethodInvestmentsStatementofOperationsDetails</Role>
      <ShortName>Investments (Equity Method Investments, Statement of Operations) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2420415 - Disclosure - Investments (Accrued Investments Income) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsAccruedInvestmentsIncomeDetails</Role>
      <ShortName>Investments (Accrued Investments Income) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2421416 - Disclosure - Investments (Net Investment Income) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsNetInvestmentIncomeDetails</Role>
      <ShortName>Investments (Net Investment Income) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2422417 - Disclosure - Investments (Realized Investment Gains Losses Net) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsRealizedInvestmentGainsLossesNetDetails</Role>
      <ShortName>Investments (Realized Investment Gains Losses Net) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2423418 - Disclosure - Investments (Net Unrealized Gains Losses on Investments by Asset Class) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsNetUnrealizedGainsLossesonInvestmentsbyAssetClassDetails</Role>
      <ShortName>Investments (Net Unrealized Gains Losses on Investments by Asset Class) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2424419 - Disclosure - Investments (Repurchase Agreements and Securities Lending) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsRepurchaseAgreementsandSecuritiesLendingDetails</Role>
      <ShortName>Investments (Repurchase Agreements and Securities Lending) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2425420 - Disclosure - Investments (Securities Pledged) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/InvestmentsSecuritiesPledgedDetails</Role>
      <ShortName>Investments (Securities Pledged) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/InvestmentsTables</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2428421 - Disclosure - Derivative Instruments (Gross Notional Amount and Fair Value of Derivatives Contracts) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DerivativeInstrumentsGrossNotionalAmountandFairValueofDerivativesContractsDetails</Role>
      <ShortName>Derivative Instruments (Gross Notional Amount and Fair Value of Derivatives Contracts) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/DerivativeInstrumentsTables</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2429422 - Disclosure - Derivative Instruments (Offsetting Balance Sheet) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DerivativeInstrumentsOffsettingBalanceSheetDetails</Role>
      <ShortName>Derivative Instruments (Offsetting Balance Sheet) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/DerivativeInstrumentsTables</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2430423 - Disclosure - Derivative Instruments (Financial Statement Classification and Impact of Derivatives Used in Qualifying and Non-qualifying Hedge Relationships) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DerivativeInstrumentsFinancialStatementClassificationandImpactofDerivativesUsedinQualifyingandNonqualifyingHedgeRelationshipsDetails</Role>
      <ShortName>Derivative Instruments (Financial Statement Classification and Impact of Derivatives Used in Qualifying and Non-qualifying Hedge Relationships) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/DerivativeInstrumentsTables</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2431424 - Disclosure - Derivative Instruments (Current Period Cash Flow Hedges in AOCI (loss) before Taxes) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DerivativeInstrumentsCurrentPeriodCashFlowHedgesinAOCIlossbeforeTaxesDetails</Role>
      <ShortName>Derivative Instruments (Current Period Cash Flow Hedges in AOCI (loss) before Taxes) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/DerivativeInstrumentsTables</ParentRole>
      <Position>57</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2432425 - Disclosure - Derivative Instruments (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DerivativeInstrumentsNarrativeDetails</Role>
      <ShortName>Derivative Instruments (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/DerivativeInstrumentsTables</ParentRole>
      <Position>58</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2435426 - Disclosure - Fair Value of Assets and Liabilities (Balances of Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesBalancesofAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails</Role>
      <ShortName>Fair Value of Assets and Liabilities (Balances of Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesTables</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2436427 - Disclosure - Fair Value of Assets and Liabilities (Quantitative Info for Level 3 Inputs) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesQuantitativeInfoforLevel3InputsDetails</Role>
      <ShortName>Fair Value of Assets and Liabilities (Quantitative Info for Level 3 Inputs) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesTables</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2437428 - Disclosure - Fair Value of Assets and Liabilities (Changes in Level 3 Assets and Liabilities) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesChangesinLevel3AssetsandLiabilitiesDetails</Role>
      <ShortName>Fair Value of Assets and Liabilities (Changes in Level 3 Assets and Liabilities) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesTables</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2438429 - Disclosure - Fair Value of Assets and Liabilities (Financial Instruments where Carrying Amounts and Fair Values May Differ) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesFinancialInstrumentswhereCarryingAmountsandFairValuesMayDifferDetails</Role>
      <ShortName>Fair Value of Assets and Liabilities (Financial Instruments where Carrying Amounts and Fair Values May Differ) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/FairValueofAssetsandLiabilitiesTables</ParentRole>
      <Position>62</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2441430 - Disclosure - Deferred Policy Acquisition Costs (Balance of and Changes in DAC) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/DeferredPolicyAcquisitionCostsBalanceofandChangesinDACDetails</Role>
      <ShortName>Deferred Policy Acquisition Costs (Balance of and Changes in DAC) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/DeferredPolicyAcquisitionCostsTables</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2445432 - Disclosure - Policyholders' Liabilities (Future Policy Benefits) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/PolicyholdersLiabilitiesFuturePolicyBenefitsDetails</Role>
      <ShortName>Policyholders' Liabilities (Future Policy Benefits) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/PolicyholdersLiabilitiesTables</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2446433 - Disclosure - Policyholders' Liabilities (Policyholders Account Balances) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/PolicyholdersLiabilitiesPolicyholdersAccountBalancesDetails</Role>
      <ShortName>Policyholders' Liabilities (Policyholders Account Balances) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/PolicyholdersLiabilitiesTables</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2447434 - Disclosure - Policyholders' Liabilities (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/PolicyholdersLiabilitiesNarrativeDetails</Role>
      <ShortName>Policyholders' Liabilities (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/PolicyholdersLiabilitiesTables</ParentRole>
      <Position>66</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2450435 - Disclosure - Certain Long-Duration Contracts with Guarantees (Variable Annuity, Variable Life, Variable Universal Life and Universal Life Contracts) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/CertainLongDurationContractswithGuaranteesVariableAnnuityVariableLifeVariableUniversalLifeandUniversalLifeContractsDetails</Role>
      <ShortName>Certain Long-Duration Contracts with Guarantees (Variable Annuity, Variable Life, Variable Universal Life and Universal Life Contracts) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2451436 - Disclosure - Certain Long-Duration Contracts With Guarantees (Separate Account Investment Options) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/CertainLongDurationContractsWithGuaranteesSeparateAccountInvestmentOptionsDetails</Role>
      <ShortName>Certain Long-Duration Contracts With Guarantees (Separate Account Investment Options) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/CertainLongDurationContractsWithGuaranteesTables</ParentRole>
      <Position>68</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2452437 - Disclosure - Certain Long-Duration Contracts with Guarantees (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/CertainLongDurationContractswithGuaranteesNarrativeDetails</Role>
      <ShortName>Certain Long-Duration Contracts with Guarantees (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2453438 - Disclosure - Certain Long-Duration Contracts with Guarantees (Liabilities for Guarantee Benefits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/CertainLongDurationContractswithGuaranteesLiabilitiesforGuaranteeBenefitsDetails</Role>
      <ShortName>Certain Long-Duration Contracts with Guarantees (Liabilities for Guarantee Benefits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2456439 - Disclosure - Reinsurance (Balance Sheet Reinsurance Results) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ReinsuranceBalanceSheetReinsuranceResultsDetails</Role>
      <ShortName>Reinsurance (Balance Sheet Reinsurance Results) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/ReinsuranceTables</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2457440 - Disclosure - Reinsurance (Reinsurance Recoverable by Counterparty) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ReinsuranceReinsuranceRecoverablebyCounterpartyDetails</Role>
      <ShortName>Reinsurance (Reinsurance Recoverable by Counterparty) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/ReinsuranceTables</ParentRole>
      <Position>72</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2458441 - Disclosure - Reinsurance (Income Statement Reinsurance Results) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ReinsuranceIncomeStatementReinsuranceResultsDetails</Role>
      <ShortName>Reinsurance (Income Statement Reinsurance Results) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/ReinsuranceTables</ParentRole>
      <Position>73</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2459442 - Disclosure - Reinsurance (Life Insurance In Force) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ReinsuranceLifeInsuranceInForceDetails</Role>
      <ShortName>Reinsurance (Life Insurance In Force) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/ReinsuranceTables</ParentRole>
      <Position>74</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2460443 - Disclosure - Reinsurance (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ReinsuranceNarrativeDetails</Role>
      <ShortName>Reinsurance (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/ReinsuranceTables</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2463444 - Disclosure - Income Taxes (Components of Income Tax Expense (Benefit)) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/IncomeTaxesComponentsofIncomeTaxExpenseBenefitDetails</Role>
      <ShortName>Income Taxes (Components of Income Tax Expense (Benefit)) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/IncomeTaxesTables</ParentRole>
      <Position>76</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2464445 - Disclosure - Income Taxes (Reconciliation To Effective Rate) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/IncomeTaxesReconciliationToEffectiveRateDetails</Role>
      <ShortName>Income Taxes (Reconciliation To Effective Rate) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/IncomeTaxesTables</ParentRole>
      <Position>77</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>2465446 - Disclosure - Income Taxes (Deferred Tax Assets and Liabilities) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/IncomeTaxesDeferredTaxAssetsandLiabilitiesDetails</Role>
      <ShortName>Income Taxes (Deferred Tax Assets and Liabilities) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/IncomeTaxesTables</ParentRole>
      <Position>78</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>2466447 - Disclosure - Income Taxes (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/IncomeTaxesNarrativeDetails</Role>
      <ShortName>Income Taxes (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/IncomeTaxesTables</ParentRole>
      <Position>79</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>2469448 - Disclosure - Equity (Accumulated Other Comprehensive Income (Loss)) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/EquityAccumulatedOtherComprehensiveIncomeLossDetails</Role>
      <ShortName>Equity (Accumulated Other Comprehensive Income (Loss)) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/EquityTables</ParentRole>
      <Position>80</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>2470449 - Disclosure - Equity (Reclassification out of Accumulated Other Comprehensive Income (Loss)) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/EquityReclassificationoutofAccumulatedOtherComprehensiveIncomeLossDetails</Role>
      <ShortName>Equity (Reclassification out of Accumulated Other Comprehensive Income (Loss)) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/EquityTables</ParentRole>
      <Position>81</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>2471450 - Disclosure - Equity (Net Unrealized Investment Gains (Losses) in AOCI) on AFS Fixed Maturity Securities with OTTI, Allowance for Credit Losses and All Other Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/EquityNetUnrealizedInvestmentGainsLossesinAOCIonAFSFixedMaturitySecuritieswithOTTIAllowanceforCreditLossesandAllOtherInvestmentsDetails</Role>
      <ShortName>Equity (Net Unrealized Investment Gains (Losses) in AOCI) on AFS Fixed Maturity Securities with OTTI, Allowance for Credit Losses and All Other Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/EquityTables</ParentRole>
      <Position>82</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>2473451 - Disclosure - Statutory Net Income and Surplus and Dividend Restrictions (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/StatutoryNetIncomeandSurplusandDividendRestrictionsNarrativeDetails</Role>
      <ShortName>Statutory Net Income and Surplus and Dividend Restrictions (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/StatutoryNetIncomeandSurplusandDividendRestrictions</ParentRole>
      <Position>83</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>2476452 - Disclosure - Related Party Transactions (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/RelatedPartyTransactionsNarrativeDetails</Role>
      <ShortName>Related Party Transactions (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/RelatedPartyTransactionsTables</ParentRole>
      <Position>84</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>2477453 - Disclosure - Related Party Transactions (Affiliated Notes Receivable) (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.prudential.com/role/RelatedPartyTransactionsAffiliatedNotesReceivableDetails</Role>
      <ShortName>Related Party Transactions (Affiliated Notes Receivable) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/RelatedPartyTransactionsTables</ParentRole>
      <Position>85</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>2478454 - Disclosure - Related Party Transactions (Affiliated Asset Transfers) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/RelatedPartyTransactionsAffiliatedAssetTransfersDetails</Role>
      <ShortName>Related Party Transactions (Affiliated Asset Transfers) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/RelatedPartyTransactionsTables</ParentRole>
      <Position>86</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>2480455 - Disclosure - Commitments and Contingent Liabilities (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/CommitmentsandContingentLiabilitiesNarrativeDetails</Role>
      <ShortName>Commitments and Contingent Liabilities (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/CommitmentsandContingentLiabilities</ParentRole>
      <Position>87</Position>
    </Report>
    <Report instance="cik1038509-20211231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>2482456 - Disclosure - Schedule I - Summary of Investments Other Than investments in Related Parties (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.prudential.com/role/ScheduleISummaryofInvestmentsOtherThaninvestmentsinRelatedPartiesDetails</Role>
      <ShortName>Schedule I - Summary of Investments Other Than investments in Related Parties (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.prudential.com/role/ScheduleISummaryofInvestmentsOtherThaninvestmentsinRelatedParties</ParentRole>
      <Position>88</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="10-K" original="cik1038509-20211231.htm">cik1038509-20211231.htm</File>
    <File>cik1038509-20211231.xsd</File>
    <File>cik1038509-20211231_cal.xml</File>
    <File>cik1038509-20211231_def.xml</File>
    <File>cik1038509-20211231_lab.xml</File>
    <File>cik1038509-20211231_pre.xml</File>
    <File>plnj-20211231xex231.htm</File>
    <File>plnj-20211231xex24.htm</File>
    <File>plnj-20211231xex311.htm</File>
    <File>plnj-20211231xex312.htm</File>
    <File>plnj-20211231xex321.htm</File>
    <File>plnj-20211231xex322.htm</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="10">http://fasb.org/srt/2021-01-31</BaseTaxonomy>
    <BaseTaxonomy items="2497">http://fasb.org/us-gaap/2021-01-31</BaseTaxonomy>
    <BaseTaxonomy items="32">http://xbrl.sec.gov/dei/2021q4</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
