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Significant Accounting Policies (Investments) (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Investment [Line Items]    
Company owned life insurance $ 2,000,000nsec_CompanyOwnedLifeInsurancePolicyFaceAmount  
Payments to acquire life insurance policies 5,000,000us-gaap_PaymentsToAcquireLifeInsurancePolicies  
Cash surrender value of life insurance 5,513,000us-gaap_CashSurrenderValueOfLifeInsurance 5,858,000us-gaap_CashSurrenderValueOfLifeInsurance
Decrease (increase) in cash surrender value of company owned life insurance 68,000us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue (73,000)us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue
Proceeds from life insurance policies $ 3,256,000us-gaap_ProceedsFromLifeInsurancePolicies $ 0us-gaap_ProceedsFromLifeInsurancePolicies
Private Equity Funds [Member] | Maximum [Member]    
Investment [Line Items]    
Investment owned, percent of net assets 1.00%us-gaap_InvestmentOwnedPercentOfNetAssets
/ us-gaap_InvestmentTypeAxis
= us-gaap_PrivateEquityFundsMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember