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

NONCONTROLLING INTERESTS - Narrative (Details)

v3.19.1

NONCONTROLLING INTERESTS - Narrative (Details) - $ / shares	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Series A-1 preferred units stated value (in dollars per share)	$ 0.01	$ 0.01
Common shares of beneficial interest, par value (in dollars per share)	$ 0.01	$ 0.01
Series A-1 Preferred Units
Class of Stock [Line Items]
Series A-1 preferred units dividend rate (percent)	6.00%
Series A-1 preferred units stated value (in dollars per share)	$ 25.00
Series A-1 Preferred Units \| NSA OP, LP
Class of Stock [Line Items]
Unit conversion ratio	1
OP units \| NSA OP, LP
Class of Stock [Line Items]
Unit conversion ratio	1
Minimum conversion period (in years)	1 year
Issuance of shares/units (in shares)	863,148
Redemptions/conversions of units (in shares)	29,910
OP units \| NSA OP, LP \| Self Storage Properties
Class of Stock [Line Items]
Issuance of shares/units (in shares)	184,040
OP units \| DownREIT Partnership
Class of Stock [Line Items]
Unit conversion ratio	1
Minimum conversion period (in years)	5 years
Issuance of shares/units (in shares)	13,475
Subordinated performance units
Class of Stock [Line Items]
Percentage of cash available for distribution used in conversion ratio calculation	110.00%
Subordinated performance units \| NSA OP, LP
Class of Stock [Line Items]
Redemptions/conversions of units (in shares)	913,680
Unit conversion, lock out period	2 years
Subordinated performance units \| NSA OP, LP \| Self Storage Properties
Class of Stock [Line Items]
Issuance of shares/units (in shares)	904,073
Subordinated performance units \| DownREIT Partnership
Class of Stock [Line Items]
Unit conversion ratio	1
Minimum conversion period (in years)	5 years
Redemptions/conversions of units (in shares)	15,377
LTIP units \| NSA OP, LP
Class of Stock [Line Items]
Unit conversion ratio	1
Issuance of shares/units (in shares)	168,896
Conversion of LTIP units into OP units (in shares)	337,847

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