S 000007299 Summary [Member] Prospectus Summary Prospectus Summary S 000007299 [Member] Bond-Debenture Portfolio Bond-Debenture Portfolio C 000020055 [Member] VC Shares VC Shares S 000007299 Summary1 [Member] Prospectus Summary Prospectus Summary cik0000855396_PRINCIPALRISKS2Member [Member] PRINCIPAL RISKS PRINCIPAL RISKS cik0000855396_PortfolioManagementRisk2Member [Member] · Portfolio Management Risk · Portfolio Management Risk cik0000855396_MarketRisk2Member [Member] · Market Risk · Market Risk cik0000855396_FixedIncomeSecuritiesRisk2Member [Member] · Fixed Income Securities Risk · Fixed Income Securities Risk cik0000855396_HighYieldSecuritiesRisk2Member [Member] · High Yield Securities Risk · High Yield Securities Risk cik0000855396_CreditRisk2Member [Member] · Credit Risk · Credit Risk cik0000855396_InterestRateRisk2Member [Member] · Interest Rate Risk · Interest Rate Risk cik0000855396_LiquidityRedemptionRisk2Member [Member] · Liquidity/Redemption Risk · Liquidity/Redemption Risk cik0000855396_EquitySecuritiesRisk2Member [Member] · Equity Securities Risk · Equity Securities Risk cik0000855396_IndustryandSectorRisk2Member [Member] · Industry and Sector Risk · Industry and Sector Risk cik0000855396_ConvertibleSecuritiesRisk2Member [Member] · Convertible Securities Risk · Convertible Securities Risk cik0000855396_GovernmentSecuritiesRisk2Member [Member] · Government Securities Risk · Government Securities Risk cik0000855396_Mortgage-RelatedandOtherAsset-BackedSecuritiesRisk2Member [Member] · Mortgage-Related and Other Asset-Backed Securities Risk · Mortgage-Related and Other Asset-Backed Securities Risk cik0000855396_Inflation-LinkedInvestmentsRisk2Member [Member] · Inflation-Linked Investments Risk · Inflation-Linked Investments Risk cik0000855396_MunicipalSecuritiesRisk2Member [Member] · Municipal Securities Risk · Municipal Securities Risk cik0000855396_SovereignDebtRisk2Member [Member] · Sovereign Debt Risk · Sovereign Debt Risk cik0000855396_ForeignandEmergingMarketCompanyRisk2Member [Member] · Foreign and Emerging Market Company Risk · Foreign and Emerging Market Company Risk cik0000855396_ForeignCurrencyRisk2Member [Member] · Foreign Currency Risk · Foreign Currency Risk cik0000855396_LoanRisk2Member [Member] · Loan Risk · Loan Risk cik0000855396_CollateralizedLoanObligationsandOtherCollateralizedObligationsRisk2Member [Member] · Collateralized Loan Obligations and Other Collateralized Obligations Risk · Collateralized Loan Obligations and Other Collateralized Obligations Risk cik0000855396_DerivativesRisk2Member [Member] · Derivatives Risk · Derivatives Risk cik0000855396_HighPortfolioTurnoverRisk2Member [Member] · High Portfolio Turnover Risk · High Portfolio Turnover Risk cik0000855396_BloombergUSAggregateBondIndex31Member [Member] Bloomberg U.S. Aggregate Bond Index Bloomberg U.S. Aggregate Bond Index cik0000855396_ICEBofAUSHighYieldConstrainedIndex33Member [Member] ICE BofA U.S. High Yield Constrained Index ICE BofA U.S. High Yield Constrained Index S 000028719 Summary [Member] Prospectus Summary Prospectus Summary S 000028719 [Member] Developing Growth Portfolio Developing Growth Portfolio C 000087850 [Member] VC Shares VC Shares S 000028719 Summary2 [Member] Prospectus Summary Prospectus Summary cik0000855396_Mid-SizedandSmallCompanyRisk2Member [Member] · Mid-Sized and Small Company Risk · Mid-Sized and Small Company Risk cik0000855396_GrowthInvestingRisk2Member [Member] · Growth Investing Risk · Growth Investing Risk cik0000855396_Russell2000GrowthIndex35Member [Member] Russell 2000® Growth Index Russell 2000® Growth Index cik0000855396_SP500Index37Member [Member] S&P 500® Index S&P 500® Index S 000007298 Summary [Member] Prospectus Summary Prospectus Summary S 000007298 [Member] Dividend Growth Portfolio Dividend Growth Portfolio C 000020054 [Member] VC Shares VC Shares S 000007298 Summary3 [Member] Prospectus Summary Prospectus Summary cik0000855396_InvestmentStrategyRisk2Member [Member] · Investment Strategy Risk · Investment Strategy Risk cik0000855396_DividendRisk2Member [Member] · Dividend Risk · Dividend Risk cik0000855396_LargeCompanyRisk2Member [Member] · Large Company Risk · Large Company Risk cik0000855396_Mid-SizedCompanyRisk2Member [Member] · Mid-Sized Company Risk · Mid-Sized Company Risk cik0000855396_ValueInvestingRisk2Member [Member] · Value Investing Risk · Value Investing Risk cik0000855396_SP500Index39Member [Member] S&P 500® Index S&P 500® Index S 000007297 Summary [Member] Prospectus Summary Prospectus Summary S 000007297 [Member] Fundamental Equity Portfolio Fundamental Equity Portfolio C 000020053 [Member] VC Shares VC Shares S 000007297 Summary4 [Member] Prospectus Summary Prospectus Summary cik0000855396_Russell1000ValueIndex311Member [Member] Russell 1000® Value Index Russell 1000® Value Index cik0000855396_Russell3000Index313Member [Member] Russell 3000® Index Russell 3000® Index cik0000855396_Russell3000ValueIndex315Member [Member] Russell 3000® Value Index Russell 3000® Value Index cik0000855396_SP500Index317Member [Member] S&P 500® Index S&P 500® Index S 000007300 Summary [Member] Prospectus Summary Prospectus Summary S 000007300 [Member] Growth and Income Portfolio Growth and Income Portfolio C 000020056 [Member] VC Shares VC Shares S 000007300 Summary5 [Member] Prospectus Summary Prospectus Summary cik0000855396_RealEstateRisk2Member [Member] · Real Estate Risk · Real Estate Risk cik0000855396_Russell1000ValueIndex319Member [Member] Russell 1000® Value Index Russell 1000® Value Index cik0000855396_SP500Index321Member [Member] S&P 500® Index S&P 500® Index cik0000855396_SP500ValueIndex323Member [Member] S&P 500® Value Index S&P 500® Value Index S 000007301 Summary [Member] Prospectus Summary Prospectus Summary S 000007301 [Member] Growth Opportunities Portfolio Growth Opportunities Portfolio C 000020057 [Member] VC Shares VC Shares S 000007301 Summary6 [Member] Prospectus Summary Prospectus Summary cik0000855396_RussellMidcapGrowthIndex325Member [Member] Russell Midcap® Growth Index Russell Midcap® Growth Index cik0000855396_RussellMidcapIndex327Member [Member] Russell Midcap® Index Russell Midcap® Index cik0000855396_SP500Index329Member [Member] S&P 500® Index S&P 500® Index S 000007304 Summary [Member] Prospectus Summary Prospectus Summary S 000007304 [Member] Mid Cap Stock Portfolio Mid Cap Stock Portfolio C 000020060 [Member] VC Shares VC Shares S 000007304 Summary7 [Member] Prospectus Summary Prospectus Summary cik0000855396_RussellMidcapValueIndex331Member [Member] Russell Midcap® Value Index Russell Midcap® Value Index cik0000855396_SPMidCap400ValueIndex333Member [Member] S&P MidCap 400® Value Index S&P MidCap 400® Value Index cik0000855396_SP500Index335Member [Member] S&P 500® Index S&P 500® Index S 000045029 Summary [Member] Prospectus Summary Prospectus Summary S 000045029 [Member] Short Duration Income Portfolio Short Duration Income Portfolio S 000045029 Summary8 [Member] Prospectus Summary Prospectus Summary C 000272081 [Member] I Shares I Shares C 000139705 [Member] VC Shares VC Shares cik0000855396_CommercialMortgage-BackedSecuritiesRisk2Member [Member] · Commercial Mortgage-Backed Securities Risk · Commercial Mortgage-Backed Securities Risk cik0000855396_ICEBofA13YearUSCorporateIndex337Member [Member] ICE BofA 1–3 Year U.S. Corporate Index ICE BofA 1–3 Year U.S. Corporate Index cik0000855396_BloombergUSAggregateBondIndex339Member [Member] Bloomberg U.S. Aggregate Bond Index Bloomberg U.S. Aggregate Bond Index S 000028721 Summary [Member] Prospectus Summary Prospectus Summary S 000028721 [Member] Total Return Portfolio Total Return Portfolio C 000087852 [Member] VC Shares VC Shares S 000028721 Summary9 [Member] Prospectus Summary Prospectus Summary cik0000855396_BloombergUSAggregateBondIndex341Member [Member] Bloomberg U.S. Aggregate Bond Index Bloomberg U.S. Aggregate Bond Index Document [Axis] Series [Axis] Prospectus Prospectus [Table] Risk/Return: Performance Measure [Axis] Class [Axis] Before Taxes After Taxes on Distributions After Taxes on Distributions and Sales Risk [Axis] All Risks [Member] Risk Lose Money [Member] Risk Not Insured [Member] Risk Nondiversified Status [Member] Risk Not Insured Depository Institution [Member] Risk Money Market Fund Price Fluctuates [Member] Risk Money Market Fund May Impose Fees or Suspend Sales [Member] Risk Money Market Fund Sponsor May Not Provide Support [Member] Risk Money Market Fund May Not Preserve Dollar [Member] Risks [Table Text Block] Risks [Table Text Block]