National Storage Affiliates Trust Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)
Notes Tables
Notes Details

SELF STORAGE PROPERTY ACQUISITIONS - Narrative (Details)

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SELF STORAGE PROPERTY ACQUISITIONS - Narrative (Details) $ in Thousands		1 Months Ended	2 Months Ended	3 Months Ended			6 Months Ended
	Jan. 01, 2015 property	Jan. 31, 2015 property	May. 31, 2015 property	Jun. 30, 2015 USD ($) property	Mar. 31, 2015 property	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) property	Jun. 30, 2014 USD ($)
Business Acquisition [Line Items]
Number of self storage properties acquired \| property	5	6	21	21	6		27
Estimated fair value of acquired self storage properties				$ 136,100			$ 136,100
Recognized fair value of real estate acquired				132,100			132,100
Pro forma revenue				3,300			4,500
Pro forma operating income				1,900			2,600
Acquisition costs				719		$ 5,089	1,318	$ 5,271
Leases, Acquired-in-Place [Member]
Business Acquisition [Line Items]
Recognized fair value of identifiable intangible assets				$ 4,000			$ 4,000
Property Subject to Operating Lease [Member]
Business Acquisition [Line Items]
Number of self storage properties acquired \| property							3
Participating Regional Operator [Member] \| Affiliated Entity [Member]
Business Acquisition [Line Items]
Number of self storage properties acquired \| property							10
Unidentified Third Parties [Member]
Business Acquisition [Line Items]
Number of self storage properties acquired \| property							17

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