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

Annual report pursuant to Section 13 and 15(d)

DEBT FINANCING - Narrative (Details)

DEBT FINANCING - Narrative (Details)		12 Months Ended
DEBT FINANCING - Narrative (Details)	Jul. 29, 2019	Dec. 31, 2023 USD ($) agency election_period	Feb. 27, 2024 USD ($)	Oct. 05, 2023 USD ($)	Mar. 24, 2023 USD ($)	Jan. 03, 2023 USD ($)	Jan. 02, 2023 USD ($)	Dec. 31, 2022 USD ($)	Aug. 30, 2022 USD ($)	Jun. 24, 2022 USD ($)	Nov. 09, 2021 USD ($)	Jul. 09, 2021 USD ($) property	May 03, 2021 USD ($)	Oct. 22, 2020 USD ($)	Aug. 30, 2019 USD ($)	Apr. 24, 2019 USD ($)	Jan. 02, 2019	Dec. 21, 2018 USD ($)
Debt Instrument [Line Items]
Carrying value		$ 3,668,757,000						$ 3,560,570,000
Unsecured debt \| Fed Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		0.50%
Credit Facility \| Revolving line of credit \| Minimum
Debt Instrument [Line Items]
Usage based fees with respect to unused portion of Revolver (percent)		0.15%
Ratings based fees if credit pricing elected (percent)		0.125%
Credit Facility \| Revolving line of credit \| Maximum
Debt Instrument [Line Items]
Usage based fees with respect to unused portion of Revolver (percent)		0.20%
Ratings based fees if credit pricing elected (percent)		0.30%
Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 1,955,000,000	$ 405,000,000
Increase limit						2,500,000,000
Credit Facility \| Line of Credit \| Revolving line of credit
Debt Instrument [Line Items]
Maximum borrowing capacity						950,000,000		650,000,000
Borrowing commitment extension fees percentage		0.0625%
Term loan extension fee percentage		0.0625%
Effective interest rate (percent)		6.71%
Revolving line of credit remaining borrowing capacity		$ 562,600,000
Carrying value		$ 381,000,000						496,000,000
Debt Instrument, Extention Periods, Number Of Elections \| election_period		2
Credit Facility \| Unsecured debt
Debt Instrument [Line Items]
Letters of credit outstanding		$ 6,400,000
Maximum total leverage ratio	60.00%
Maximum total leverage ratio allowable within two quarters of material acquisition	65.00%
Minimum fixed charge coverage ratio	1.5
Maximum secured indebtedness to gross asset value (as a percent)	40.00%
Maximum unsecured debt to unencumbered asset value ratio	60.00%
Maximum unsecured debt to unencumbered asset value ratio allowable within two quarters of material acquisition	65.00%
Minimum encumbered adjusted net operating income to unsecured interest expense ratio	2.0
Credit Facility \| Unsecured debt \| Fed Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		0.50%
Credit Facility \| Unsecured debt \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		1.00%
Credit Facility \| Unsecured debt \| Secured Overnight Financing Rate (SOFR) \| Minimum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		1.10%
Credit rating pricing election (percent)		0.725%
Credit Facility \| Unsecured debt \| Secured Overnight Financing Rate (SOFR) \| Maximum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		1.80%
Credit rating pricing election (percent)		1.65%
Credit Facility \| Unsecured debt \| Base Rate \| Minimum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		0.10%
Credit rating pricing election (percent)		0.00%
Credit Facility \| Unsecured debt \| Base Rate \| Maximum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		0.80%
Credit rating pricing election (percent)		0.65%
Credit Facility \| Unsecured debt \| Term loan A
Debt Instrument [Line Items]
Maximum borrowing capacity						125,000,000
Carrying value								125,000,000
Credit Facility \| Unsecured debt \| Term loan B
Debt Instrument [Line Items]
Maximum borrowing capacity						275,000,000	250,000,000
Effective interest rate (percent)		3.28%
Carrying value		$ 275,000,000						250,000,000
Credit Facility \| Unsecured debt \| Term loan B \| Subsequent Event
Debt Instrument [Line Items]
Carrying value			$ 130,000,000
Credit Facility \| Unsecured debt \| Term loan C
Debt Instrument [Line Items]
Maximum borrowing capacity						325,000,000	225,000,000
Effective interest rate (percent)		4.07%
Carrying value		$ 325,000,000						225,000,000
Credit Facility \| Unsecured debt \| Term loan D
Debt Instrument [Line Items]
Maximum borrowing capacity						275,000,000	175,000,000
Effective interest rate (percent)		4.05%
Carrying value		$ 275,000,000						175,000,000
Credit Facility \| Unsecured debt \| Term loan E
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 130,000,000	$ 125,000,000
Effective interest rate (percent)		4.93%
Carrying value		$ 130,000,000						125,000,000
Term Loan Facility \| Unsecured debt
Debt Instrument [Line Items]
Maximum borrowing capacity								175,000,000
2028 Term loan facility \| Unsecured debt
Debt Instrument [Line Items]
Debt issued					$ 75,000,000
Maximum borrowing capacity if expansion option is exercised																		$ 125,000,000
Minimum number of rating agencies required \| agency		2
Carrying value								75,000,000
2028 Term loan facility \| Unsecured debt \| Fed Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		0.50%
2028 Term loan facility \| Unsecured debt \| Base Rate \| Minimum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		0.80%
Credit rating pricing election (percent)		0.40%
2028 Term loan facility \| Unsecured debt \| Base Rate \| Maximum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		1.35%
Credit rating pricing election (percent)		1.25%
2028 Term loan facility \| Unsecured debt \| London Inter Bank Offered Rate
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		1.00%
2028 Term loan facility \| Unsecured debt \| London Inter Bank Offered Rate \| Minimum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		1.80%
Credit rating pricing election (percent)		1.40%
2028 Term loan facility \| Unsecured debt \| London Inter Bank Offered Rate \| Maximum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		2.35%
Credit rating pricing election (percent)		2.25%
2028 Term loan facility \| Unsecured debt \| Term loan E
Debt Instrument [Line Items]
Effective interest rate (percent)																	4.62%
Carrying value		$ 75,000,000
A2029 Term Loan Facility \| Unsecured debt
Debt Instrument [Line Items]
Debt issued																$ 100,000,000
Minimum number of rating agencies required \| agency		2
A2029 Term Loan Facility \| Unsecured debt \| Interest rate swap
Debt Instrument [Line Items]
Aggregate notional amount																$ 100,000,000
A2029 Term Loan Facility \| Unsecured debt \| Fed Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		0.50%
A2029 Term Loan Facility \| Unsecured debt \| Base Rate \| Minimum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		0.85%
Credit rating pricing election (percent)		0.40%
A2029 Term Loan Facility \| Unsecured debt \| Base Rate \| Maximum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		1.30%
Credit rating pricing election (percent)		1.25%
A2029 Term Loan Facility \| Unsecured debt \| London Inter Bank Offered Rate
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		1.00%
A2029 Term Loan Facility \| Unsecured debt \| London Inter Bank Offered Rate \| Minimum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		1.85%
Credit rating pricing election (percent)		1.40%
A2029 Term Loan Facility \| Unsecured debt \| London Inter Bank Offered Rate \| Maximum
Debt Instrument [Line Items]
Leverage based applicable margin (percent)		2.30%
Credit rating pricing election (percent)		2.25%
June 2029 term loan facility \| Unsecured debt
Debt Instrument [Line Items]
Maximum borrowing capacity										$ 285,000,000
Increase limit										15,000,000
Effective interest rate (percent)		5.37%
Higher borrowing capacity option										$ 300,000,000
Carrying value		$ 285,000,000						285,000,000
June 2029 term loan facility \| Unsecured debt \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		1.00%
June 2029 term loan facility \| Unsecured debt \| Secured Overnight Financing Rate (SOFR) \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		1.55%
June 2029 term loan facility \| Unsecured debt \| Secured Overnight Financing Rate (SOFR) \| Minimum \| Variable Rate Component One
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		1.075%
June 2029 term loan facility \| Unsecured debt \| Secured Overnight Financing Rate (SOFR) \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		2.20%
June 2029 term loan facility \| Unsecured debt \| Secured Overnight Financing Rate (SOFR) \| Maximum \| Variable Rate Component One
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		2.20%
June 2029 term loan facility \| Unsecured debt \| Base Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		0.55%
June 2029 term loan facility \| Unsecured debt \| Base Rate \| Minimum \| Variable Rate Component One
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		0.075%
June 2029 term loan facility \| Unsecured debt \| Base Rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		1.20%
June 2029 term loan facility \| Unsecured debt \| Base Rate \| Maximum \| Variable Rate Component One
Debt Instrument [Line Items]
Basis spread on variable rate (percent)		1.20%
2029 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		3.98%													3.98%
Debt issued															$ 100,000,000
Carrying value		$ 100,000,000						100,000,000
August 2031 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		4.08%													4.08%
Debt issued															$ 50,000,000
Carrying value		$ 50,000,000						50,000,000
August 2030 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		2.99%
Debt issued														$ 150,000,000
Carrying value		$ 150,000,000						150,000,000
A2032 Senior Notes \| Unsecured debt
Debt Instrument [Line Items]
Debt issued														$ 100,000,000
May 2026 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		2.16%											2.16%
Carrying value		$ 35,000,000						35,000,000					$ 35,000,000
May 2031 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		3.00%											3.00%
Carrying value		$ 90,000,000						90,000,000					$ 90,000,000
May 2033 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		3.10%											3.10%
Carrying value		$ 55,000,000						55,000,000					$ 55,000,000
November 2030 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		2.72%									2.72%
Carrying value		$ 75,000,000						75,000,000			$ 75,000,000
November 2031 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		2.81%									2.81%
Carrying value		$ 175,000,000						175,000,000			$ 175,000,000
November 2033 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		2.96%									2.96%
Carrying value		$ 125,000,000						125,000,000			$ 125,000,000
2036 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		3.06%									3.06%
Carrying value		$ 75,000,000						75,000,000			$ 75,000,000
November 2032 Senior Unsecured Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		5.06%							5.06%
Carrying value		$ 200,000,000						200,000,000
Senior unsecured notes									$ 200,000,000
2028 Senior Notes \| Unsecured debt
Debt Instrument [Line Items]
Effective interest rate (percent)		5.75%
Debt issued		$ 120,000,000
Interest rate (percent)		5.61%
October 2026 Notes
Debt Instrument [Line Items]
Debt issued				$ 65,000,000
Interest rate (percent)				6.46%
October 2028 Notes
Debt Instrument [Line Items]
Debt issued				$ 100,000,000
Interest rate (percent)				6.55%
October 2030 Notes
Debt Instrument [Line Items]
Debt issued				$ 35,000,000
Interest rate (percent)				6.66%
October 2033 Notes
Debt Instrument [Line Items]
Debt issued				$ 50,000,000
Interest rate (percent)				6.73%
Fixed rate mortgages payable \| Mortgages
Debt Instrument [Line Items]
Effective interest rate (percent)		3.61%
Carrying value		$ 222,757,000						$ 299,570,000
Fixed rate mortgages payable \| Mortgages \| Minimum
Debt Instrument [Line Items]
Effective interest rate (percent)		2.77%
Fixed rate mortgages payable \| Mortgages \| Maximum
Debt Instrument [Line Items]
Effective interest rate (percent)		4.34%
2028 Fixed Rate Mortgage Payable \| Mortgages
Debt Instrument [Line Items]
Debt issued												$ 88,000,000
Interest rate (percent)												2.77%
Number of properties securing debt \| property												8