National Storage Affiliates Trust Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 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 AND DISPOSITIONS - Narrative (Details)

v3.10.0.1

SELF STORAGE PROPERTY ACQUISITIONS AND DISPOSITIONS - Narrative (Details) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018 USD ($) property	Sep. 30, 2018 property	Jun. 30, 2018 property	Mar. 31, 2018 property	Dec. 31, 2017 USD ($) property	Sep. 30, 2017 property	Jun. 30, 2017 property	Mar. 31, 2017 property	Dec. 31, 2018 USD ($) property	Dec. 31, 2017 USD ($) property
Business Acquisition [Line Items]
Acquisition-related costs capitalized									$ 1.9	$ 3.6
Recognized fair value allocated to real estate	$ 347.5				$ 416.3				347.5	416.3
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Debt Adjustment	0.2								0.2
Pro forma revenue									21.9	15.5
Pro forma operating income									$ 2.5	$ 0.5
Number Of Real Estate Assets Held-For-Sale, Sold \| property									2
Number of self storage properties sold \| property										3
Gross selling price of self storage property sold	5.5				17.8				$ 5.5	$ 17.8
Gain on sale of self storage properties									0.4	5.7
Customer In-Place Leases [Member]
Business Acquisition [Line Items]
Recognized fair value allocated to in-place leases	9.1				10.5				$ 9.1	$ 10.5
Participating Regional Operator [Member] \| Affiliated Entity [Member]
Business Acquisition [Line Items]
Number of self storage properties acquired \| property									4	10
Estimated fair value of acquired self storage properties	$ 23.1				$ 73.2				$ 23.1	$ 73.2
2018 Acquisitions [Member]
Business Acquisition [Line Items]
Number of self storage properties acquired \| property	7	13	12	25					57
Estimated fair value of acquired self storage properties	$ 356.6								$ 356.6
2017 Acquisitions [Member]
Business Acquisition [Line Items]
Number of self storage properties acquired \| property					31	19	10	5		65
Estimated fair value of acquired self storage properties					$ 426.8					$ 426.8

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