Property Acquisitions and Dispositions - Acquisitions of Operating Stores (Details) $ in Thousands								6 Months Ended	12 Months Ended
	Nov. 17, 2016 USD ($) store	Nov. 02, 2016 USD ($) property shares	Sep. 16, 2016 USD ($) store	May 21, 2016 store	Feb. 02, 2016 USD ($) store	Jun. 18, 2015 USD ($) Property shares	Apr. 15, 2015 USD ($) Property shares	Jun. 30, 2016 USD ($) property shares	Dec. 31, 2016 USD ($) property shares	Dec. 31, 2015 USD ($) property shares
Business Acquisition [Line Items]
Number of stores | property									99	171
Total									$ 1,086,645	$ 1,606,509
Cash Paid									995,759	1,517,196
Notes payable assumed									9,723	0
Real Estate Property Acquisition Notes Issued To/From Seller										15,610
Net Liabilities/(Assets) Assumed									6,928	(68,696)
Value of OP Units Issued									$ 74,235	$ 142,399
Number of OP Units Issued | shares									2,779,050	2,043,613,000
Real estate assets									$ 1,149,936	$ 1,607,979
Arizona Property Dec 21, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 9,513
Cash Paid									9,500
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									13
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 9,513
Washington Property Nov 22, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 12,743
Cash Paid									12,726
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									17
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 12,743
Hawaii Property Nov 18, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									2
Total									$ 15,394
Cash Paid									15,356
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									38
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 15,394
Georgia Property Nov 17, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 7,998
Cash Paid									8,009
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(11)
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 7,998
Various states Properties Nov 17, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									11
Total									$ 152,953
Cash Paid									153,017
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(64)
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 161,072
California Property Nov 17, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 17,892
Cash Paid									17,860
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									32
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 17,892
North Carolina Property Nov 14, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 13,242
Cash Paid									13,241
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									1
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 13,242
Illinois Property Nov 8, 2016 [Member] [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 12,304
Cash Paid									9
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									139
Value of OP Units Issued									$ 12,156
Number of OP Units Issued | shares									486,244
Real estate assets									$ 12,304
Maryland Property Nov 2, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property		1
Total									14,807
Cash Paid									9,040
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(75)
Value of OP Units Issued		$ 5,842
Number of OP Units Issued | shares		77,575,000
Real estate assets									$ 14,807
Texas Property Oct 25, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 6,743
Cash Paid									6,685
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									58
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 6,743
Minnesota Property Oct 12, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 17,744
Cash Paid									17,729
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									15
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 17,744
Texas Property Oct 6, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									3
Total									$ 22,302
Cash Paid									22,131
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									171
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 22,302
Utah Property Oct 4, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 8,429
Cash Paid									3,750
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									4,679
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 8,429
California Property Oct 4, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 8,500
Cash Paid									8,516
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(16)
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 8,500
California Property Sep 21,2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 13,800
Cash Paid									13,782
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									18
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 13,800
Various States Properties Sep 16, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									23
Total									$ 237,542
Cash Paid									237,800
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(258)
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 248,530
California Property Aug 31, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 3,990
Cash Paid									3,998
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(8)
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 3,990
Texas Property Aug 12, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 9,993
Cash Paid									9,915
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									78
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 9,993
Hawaii Property Jul 14, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 30,955
Cash Paid									30,850
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									105
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 30,955
Massachusetts Property Jun 30, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 13,807
Cash Paid									13,751
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									56
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 13,807
Georgia Property Jun 30, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property								1
Total									7,900
Cash Paid									6,696
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									4
Value of OP Units Issued								$ 1,200
Number of OP Units Issued | shares								13,764
Real estate assets									7,900
Illinois Properties Jun 10, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | store				4
Total									55,851
Cash Paid									0
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									814
Value of OP Units Issued									$ 55,037
Number of OP Units Issued | shares									2,201,467
Real estate assets									$ 55,851
Texas Property Jun 2, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									4
Total									$ 37,478
Cash Paid									37,246
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									232
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 37,478
South Carolina Property May 10, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 8,249
Cash Paid									8,230
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									19
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 8,249
Washington, DC Property May 5, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 32,968
Cash Paid									23,163
Notes payable assumed									9,723
Net Liabilities/(Assets) Assumed									82
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 32,968
Indiana Property Apr 22, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									5
Total									$ 26,983
Cash Paid									26,849
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									134
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 26,983
Colorado Property Apr 19, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 7,904
Cash Paid									7,869
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									35
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 7,904
Arizona Property Apr 18, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 8,154
Cash Paid									8,029
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									125
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 8,154
Texas Property Apr 15, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 10,978
Cash Paid									10,922
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									56
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 10,978
Arizona Property Apr 5, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 5,000
Cash Paid									4,999
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									1
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 5,000
Hawaii Property Apr 5, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 28,992
Cash Paid									28,935
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									57
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 28,992
New Mexico Property Mar 29, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 10,958
Cash Paid									10,928
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									30
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 10,958
New Mexico Property Mar 29, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 17,940
Cash Paid									17,905
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									35
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 17,940
Georgia Property Mar 29, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									3
Total									$ 25,087
Cash Paid									25,069
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									18
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 25,087
Texas Property Mar 21, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 9,994
Cash Paid									9,969
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									25
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 9,994
Illinois Property Feb 25, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 16,721
Cash Paid									16,738
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(17)
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 16,721
Massachusetts Property Feb 16, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 16,169
Cash Paid									16,174
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(5)
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 16,169
Various States Properties Feb 2, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									6
Total									$ 53,898
Cash Paid									53,940
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									(42)
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets					$ 98,082
Extra Space Of Sacramento One LLC [Member]
Business Acquisition [Line Items]
Gain on bargain purchase of acquisition									$ 1,100
Texas Property Jan 14, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									3
Total									$ 22,625
Cash Paid									22,523
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									102
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 22,625
Florida Property Jan 12, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									1
Total									$ 9,001
Cash Paid									8,980
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									21
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 9,001
Texas Property Jan 7, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									3
Total									$ 27,537
Cash Paid									27,435
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									102
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 27,537
New Mexico Property Jan 7, 2016 [Member]
Business Acquisition [Line Items]
Number of stores | property									2
Total									$ 15,607
Cash Paid									15,495
Notes payable assumed									0
Net Liabilities/(Assets) Assumed									112
Value of OP Units Issued									$ 0
Number of OP Units Issued | shares									0
Real estate assets									$ 15,607
California Property Dec 11, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 9,708
Cash Paid										9,712
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										(4)
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 9,708
North Carolina Property Dec 8, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 5,301
Cash Paid										5,327
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										(26)
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 5,301
Oregon Property Nov 24, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 9,992
Cash Paid										9,994
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										(2)
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 9,992
Florida Property Nov 19, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										3,000
Total										$ 20,003
Cash Paid										19,951
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										52
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 20,003
Texas Property Nov 16, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 14,396
Cash Paid										7,115
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										60
Value of OP Units Issued										$ 7,221
Number of OP Units Issued | shares										91,434,000
Real estate assets										$ 14,396
Texas Property Oct 23, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 8,700
Cash Paid										8,678
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										22
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 8,700
New Jersey Property Oct 7, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 7,240
Cash Paid										7,204
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										36
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 7,240
Various Property Oct 1, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										122,000
Total										$ 1,176,893
Cash Paid										1,218,173
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										(69,936)
Value of OP Units Issued										$ 28,656
Number of OP Units Issued | shares										376,848,000
Real estate assets										$ 1,176,898
Maryland Property Sep 10, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 6,091
Cash Paid										6,109
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										(18)
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 6,091
North Carolina Property Jun 19, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 6,976
Cash Paid										6,915
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										61
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 6,976
Florida Property Jun 18, 2015 [Member]
Business Acquisition [Line Items]
Number of stores						1				1,000
Total										$ 17,547
Cash Paid										12,567
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										207
Value of OP Units Issued						$ 4,773				$ 4,773
Number of OP Units Issued | shares						71,054				71,054,000
Real estate assets										$ 17,547
Florida Property Jun 17, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 4,923
Cash Paid										359
Notes payable assumed										0
Real Estate Property Acquisition Notes Issued To/From Seller										4,601
Net Liabilities/(Assets) Assumed										(37)
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 6,023
Illinois Property Jun 8, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 10,049
Cash Paid										9,973
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										76
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 10,049
Massachusetts Property May 13, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 12,500
Cash Paid										12,503
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										(3)
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 12,500
Georgia Property May 7, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 6,496
Cash Paid										6,456
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										40
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 6,496
North Carolina Property May 5, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 10,994
Cash Paid										10,963
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										31
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 10,994
Georgia Property Apr 24, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 6,498
Cash Paid										6,449
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										49
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 6,498
Arizona, Texas Property Apr 15, 2015 [Member]
Business Acquisition [Line Items]
Number of stores							22			22,000
Total										$ 177,673
Cash Paid										75,102
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										822
Value of OP Units Issued							$ 101,749			$ 101,749
Number of OP Units Issued | shares							1,504,277			1,504,277,000
Real estate assets										$ 177,673
Texas Property Apr 14, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 8,640
Cash Paid										8,570
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										70
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 8,640
California Property Mar 30, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 12,334
Cash Paid										1,700
Notes payable assumed										0
Real Estate Property Acquisition Notes Issued To/From Seller										11,009
Net Liabilities/(Assets) Assumed										(375)
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 12,699
Equity Ownership (as a percent)									100.00%
Cash portion of payment for acquisition									$ 1,700
Company held mortgage notes receivable eliminated as a result of the acquisition									11,009
Previous equity interest, fair value									365
Non-cash gain									$ 1,629
South Carolina Property Mar 30, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										2,000
Total										$ 13,136
Cash Paid										13,114
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										22
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 13,136
Virginia Property Mar 17, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 4,996
Cash Paid										4,988
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										8
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 4,996
Texas Property Feb 24, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										1,000
Total										$ 13,554
Cash Paid										13,503
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										51
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 13,554
Texas Property Jan 13, 2015 [Member]
Business Acquisition [Line Items]
Number of stores | property										3,000
Total										$ 41,869
Cash Paid										41,771
Notes payable assumed										0
Net Liabilities/(Assets) Assumed										98
Value of OP Units Issued										$ 0
Number of OP Units Issued | shares										0
Real estate assets										$ 41,869
ESS PRISA II LLC Joint Venture [Member]
Business Acquisition [Line Items]
Number of acquired stores | store			23
Equity method ownership percentage			4.40%
Extra Space Properties 131 LLC [Member]
Business Acquisition [Line Items]
Real estate assets			$ 248,530
Equity Ownership (as a percent)			100.00%
Net carrying amount of properties distributed			$ 4,326
Previous equity interest			10,988
Step acquisition, equity interest in acquiree, remeasurement gain			$ 6,778
Number of transferred stores | store			23
VRS Self Storage LLC Joint Venture [Member]
Business Acquisition [Line Items]
Number of acquired stores | store					6
Equity method ownership percentage					45.00%
Extra Space Properties One Two Two LLC [Member]
Business Acquisition [Line Items]
Number of acquired stores | store					6
Equity Ownership (as a percent)					100.00%
Net carrying amount of properties distributed					$ 17,261
Previous equity interest					44,184
Step acquisition, equity interest in acquiree, remeasurement gain					$ 26,923
Number of transferred stores | store					6
ESS WCOT LLC Joint Venture [Member]
Business Acquisition [Line Items]
Real estate assets	$ 161,072
Number of acquired stores | store	11
Equity method ownership percentage	5.00%
Equity Ownership (as a percent)	100.00%
Net carrying amount of properties distributed	$ 68,814
Amount paid to acquire joint venture partners interests	$ 153,304
Additional interest acquired in the venture	94.96%
Previous equity interest	$ 8,119
Step acquisition, equity interest in acquiree, remeasurement gain	$ 4,651
Prudential Real Estate and Affiliates [Member] | ESS PRISA II LLC Joint Venture [Member]
Business Acquisition [Line Items]
Equity Ownership (as a percent)			95.60%
Prudential Real Estate and Affiliates [Member] | Extra Space Properties 131 LLC [Member]
Business Acquisition [Line Items]
Equity Ownership (as a percent)			95.60%
Amount paid to acquire joint venture partners interests			$ 238,679
Prudential Real Estate and Affiliates [Member] | VRS Self Storage LLC Joint Venture [Member]
Business Acquisition [Line Items]
Additional interest acquired in the venture					55.00%
Prudential Real Estate and Affiliates [Member] | Extra Space Properties One Two Two LLC [Member]
Business Acquisition [Line Items]
Amount paid to acquire joint venture partners interests					$ 53,940
Additional interest acquired in the venture					55.00%
ESS Prisa Two LLC [Member]
Business Acquisition [Line Items]
Number of stores | store			42