ORGANIZATION AND NATURE OF OPERATIONS (Details) (USD $) In Millions, except Share data, unless otherwise specified
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3 Months Ended |
0 Months Ended |
1 Months Ended |
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Mar. 31, 2015
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Apr. 28, 2015
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May 18, 2015
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Dec. 31, 2014
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Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |
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Number of self storage properties owned |
225us-gaap_NumberOfRealEstateProperties
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Number of states that self storage properties are owned in |
13us-gaap_NumberOfStatesInWhichEntityOperates
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Rentable square feet in self storage properties |
12,400,000us-gaap_NetRentableArea
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Number of storage units owned |
100,000nsa_NumberofStorageUnits
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Number of participating regional operators |
5nsa_NumberOfBusinessesOperatedByAffiliates
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National Storage Affiliates Holdings LLC [Member] | National Storage Affiliates Trust [Member] |
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Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |
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Percentage of NSA owned by NSA Holdings |
100.00%nsa_InvestmentOwnershipPercentage / dei_LegalEntityAxis = nsa_NationalStorageAffiliatesHoldingsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = nsa_NationalStorageAffiliatesTrustMember
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National Storage Affiliates Holdings LLC [Member] | National Storage Affiliates Trust [Member] | Common Shares [Member] |
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Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |
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Shares owned by NSA Holdings (in shares) |
1,000us-gaap_InvestmentOwnedBalanceShares / us-gaap_InvestmentTypeAxis = us-gaap_CommonStockMember / dei_LegalEntityAxis = nsa_NationalStorageAffiliatesHoldingsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = nsa_NationalStorageAffiliatesTrustMember
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National Storage Affiliates Holdings LLC [Member] | NSA OP, LP [Member] | OP units [Member] |
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Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |
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Shares owned by NSA Holdings (in shares) |
126,400us-gaap_InvestmentOwnedBalanceShares / us-gaap_InvestmentTypeAxis = nsa_ClassAUnitsMember / dei_LegalEntityAxis = nsa_NationalStorageAffiliatesHoldingsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = nsa_NSAOPLPMember
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126,400us-gaap_InvestmentOwnedBalanceShares / us-gaap_InvestmentTypeAxis = nsa_ClassAUnitsMember / dei_LegalEntityAxis = nsa_NationalStorageAffiliatesHoldingsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = nsa_NSAOPLPMember
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Subsequent Event [Member] | Common Shares [Member] | IPO [Member] |
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Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |
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Shares offered including underwriters option |
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20,000,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_IPOMember
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Total net proceeds from initial public offering |
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$ 236.4us-gaap_ProceedsFromIssuanceInitialPublicOffering / us-gaap_StatementEquityComponentsAxis = us-gaap_CommonStockMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember / us-gaap_SubsidiarySaleOfStockAxis = us-gaap_IPOMember
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Subsequent Event [Member] | National Storage Affiliates Holdings LLC [Member] | National Storage Affiliates Trust [Member] | Common Shares [Member] |
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Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |
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Shares owned by NSA Holdings (in shares) |
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1,000us-gaap_InvestmentOwnedBalanceShares / us-gaap_InvestmentTypeAxis = us-gaap_CommonStockMember / dei_LegalEntityAxis = nsa_NationalStorageAffiliatesHoldingsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = nsa_NationalStorageAffiliatesTrustMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
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Common Shares [Member] |
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Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |
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Common share par value (in dollars per share) |
0.01us-gaap_CommonStockNoParValue / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember
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Common Shares [Member] | Subsequent Event [Member] |
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Subsidiary of Limited Liability Company or Limited Partnership [Line Items] |
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Shares offered including underwriters option |
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23,000,000us-gaap_StockIssuedDuringPeriodSharesNewIssues / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
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Total net proceeds from initial public offering |
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$ 273.0us-gaap_ProceedsFromIssuanceInitialPublicOffering / us-gaap_StatementClassOfStockAxis = us-gaap_CommonStockMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
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