Life Storage 10-Q 3 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Oct. 18, 2017
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Trading Symbol	LSI
Entity Registrant Name	LIFE STORAGE, INC.
Entity Central Index Key	944,314
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		46,536,812
Life Storage LP [Member]
Document Information [Line Items]
Entity Registrant Name	LIFE STORAGE LP
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Investment in storage facilities:
Land	$ 785,929	$ 786,764
Building, equipment, and construction in progress	3,520,466	3,456,544
Real estate investment property, at cost, total	4,306,395	4,243,308
Less: accumulated depreciation	(601,854)	(535,704)
Investment in storage facilities, net	3,704,541	3,707,604
Cash and cash equivalents	6,096	23,685
Accounts receivable	7,105	5,469
Receivable from unconsolidated joint ventures	869	1,223
Investment in unconsolidated joint ventures	134,232	67,300
Prepaid expenses	9,102	6,649
Trade name	16,500	16,500
Other assets	5,890	29,554
Total Assets	3,884,335	3,857,984
Liabilities
Line of credit	329,000	253,000
Term notes, net	1,388,808	1,387,525
Accounts payable and accrued liabilities	73,597	75,132
Deferred revenue	9,496	9,700
Fair value of interest rate swap agreements	10,923	13,015
Mortgages payable	12,764	13,027
Total Liabilities	1,824,588	1,751,399
Noncontrolling redeemable Operating Partnership Units at redemption value	17,638	18,091
Shareholders' Equity/ Partners' Capital
Common stock $.01 par value, 100,000,000 shares authorized, 46,536,812 shares outstanding at September 30, 2017 (46,454,606 at December 31, 2016)	465	464
Additional paid-in capital	2,360,881	2,348,567
Dividends in excess of net income	(300,423)	(239,062)
Accumulated other comprehensive loss	(18,814)	(21,475)
Total Shareholders’ Equity	2,042,109	2,088,494
Noncontrolling interest in consolidated subsidiary	0	0
Total Equity	2,042,109	2,088,494
Total Liabilities and Shareholders' Equity/ Partners' Capital	3,884,335	3,857,984
Life Storage LP [Member]
Investment in storage facilities:
Land	785,929	786,764
Building, equipment, and construction in progress	3,520,466	3,456,544
Real estate investment property, at cost, total	4,306,395	4,243,308
Less: accumulated depreciation	(601,854)	(535,704)
Investment in storage facilities, net	3,704,541	3,707,604
Cash and cash equivalents	6,096	23,685
Accounts receivable	7,105	5,469
Receivable from unconsolidated joint ventures	869	1,223
Investment in unconsolidated joint ventures	134,232	67,300
Prepaid expenses	9,102	6,649
Trade name	16,500	16,500
Other assets	5,890	29,554
Total Assets	3,884,335	3,857,984
Liabilities
Line of credit	329,000	253,000
Term notes, net	1,388,808	1,387,525
Accounts payable and accrued liabilities	73,597	75,132
Deferred revenue	9,496	9,700
Fair value of interest rate swap agreements	10,923	13,015
Mortgages payable	12,764	13,027
Total Liabilities	1,824,588	1,751,399
Limited partners’ redeemable capital interest at redemption value (217,481 units outstanding at September 30, 2017 and December 31, 2016)	17,638	18,091
Shareholders' Equity/ Partners' Capital
General partner (467,543 and 466,721 units outstanding at September 30, 2017 and December 31, 2016, respectively)	20,597	21,065
Limited partners (46,069,269 and 45,987,885 units outstanding at September 30, 2017 and December 31, 2016, respectively)	2,040,326	2,088,904
Accumulated other comprehensive loss	(18,814)	(21,475)
Total Controlling Partners’ Capital	2,042,109	2,088,494
Noncontrolling interest in consolidated subsidiary	0	0
Total Partners' Capital	2,042,109	2,088,494
Total Liabilities and Shareholders' Equity/ Partners' Capital	$ 3,884,335	$ 3,857,984

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares outstanding	46,536,812	46,454,606
Limited partner, units outstanding	217,481	217,481
Life Storage LP [Member]
General partner, units outstanding	467,543	466,721
Limited partner, units outstanding	46,069,269	45,987,885
Life Storage LP [Member] | Limited Partners Redeemable Capital Interest at Redemption Value [Member]
Limited partner, units outstanding	217,481	217,481

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues
Rental income	$ 124,044	$ 118,319	$ 363,284	$ 308,655
Other operating income	11,524	9,482	33,389	25,274
Total operating revenues	135,568	127,801	396,673	333,929
Expenses
Property operations and maintenance	32,662	28,382	92,178	74,396
Real estate taxes	14,498	13,102	43,431	34,670
General and administrative	10,914	10,909	38,309	31,486
Acquisition costs		25,220		29,297
Operating leases of storage facilities	141		283
Depreciation and amortization	26,149	41,405	101,896	76,082
Total operating expenses	84,364	119,018	276,097	245,931
Income from operations	51,204	8,783	120,576	87,998
Other income (expenses)
Interest expense	(16,290)	(14,647)	(47,216)	(32,024)
Interest expense – bridge financing commitment fee				(7,329)
Interest income	1	13	4	56
Gain on sale of storage facilities				15,270
Equity in income of joint ventures	752	882	2,259	2,795
Net income (loss)	35,667	(4,969)	75,623	66,766
Net (income) loss attributable to noncontrolling interest in the Operating Partnership	(171)	21	(343)	(317)
Net loss attributable to noncontrolling interest in consolidated subsidiary		210		609
Net income (loss) attributable to common shareholders/unitholders	$ 35,496	$ (4,738)	$ 75,280	$ 67,058
Earnings (loss) per common share/unit attributable to common shareholders/unitholders - basic	$ 0.76	$ (0.10)	$ 1.62	$ 1.59
Earnings (loss) per common share/unit attributable to common shareholders/unitholders - diluted	$ 0.76	$ (0.10)	$ 1.62	$ 1.58
Common shares/units used in basic earnings (loss) per share/unit calculation	46,415,782	46,139,079	46,361,747	42,176,762
Common shares/units used in diluted earnings (loss) per share/unit calculation	46,520,311	46,139,079	46,472,294	42,414,623
Dividends/distributions declared per common share/unit	$ 1	$ 0.95	$ 2.95	$ 2.75
Life Storage LP [Member]
Revenues
Rental income	$ 124,044	$ 118,319	$ 363,284	$ 308,655
Other operating income	11,524	9,482	33,389	25,274
Total operating revenues	135,568	127,801	396,673	333,929
Expenses
Property operations and maintenance	32,662	28,382	92,178	74,396
Real estate taxes	14,498	13,102	43,431	34,670
General and administrative	10,914	10,909	38,309	31,486
Acquisition costs		25,220		29,297
Operating leases of storage facilities	141		283
Depreciation and amortization	26,149	41,405	101,896	76,082
Total operating expenses	84,364	119,018	276,097	245,931
Income from operations	51,204	8,783	120,576	87,998
Other income (expenses)
Interest expense	(16,290)	(14,647)	(47,216)	(32,024)
Interest expense – bridge financing commitment fee				(7,329)
Interest income	1	13	4	56
Gain on sale of storage facilities				15,270
Equity in income of joint ventures	752	882	2,259	2,795
Net income (loss)	35,667	(4,969)	75,623	66,766
Net (income) loss attributable to noncontrolling interest in the Operating Partnership	(171)	21	(343)	(317)
Net loss attributable to noncontrolling interest in consolidated subsidiary		210		609
Net income (loss) attributable to common shareholders/unitholders	$ 35,496	$ (4,738)	$ 75,280	$ 67,058
Earnings (loss) per common share/unit attributable to common shareholders/unitholders - basic	$ 0.76	$ (0.10)	$ 1.62	$ 1.59
Earnings (loss) per common share/unit attributable to common shareholders/unitholders - diluted	$ 0.76	$ (0.10)	$ 1.62	$ 1.58
Common shares/units used in basic earnings (loss) per share/unit calculation	46,415,782	46,139,079	46,361,747	42,176,762
Common shares/units used in diluted earnings (loss) per share/unit calculation	46,520,311	46,139,079	46,472,294	42,414,623
Dividends/distributions declared per common share/unit	$ 1	$ 0.95	$ 2.95	$ 2.75
Net income (loss) attributable to general partner	$ 357	$ (47)	$ 756	$ 674
Net income (loss) attributable to limited partners	$ 35,139	$ (4,691)	$ 74,524	$ 66,384

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net income (loss)	$ 35,667	$ (4,969)	$ 75,623	$ 66,766
Other comprehensive income (loss):
Effective portion of gain (loss) on derivatives net of reclassification to interest expense	802	2,931	2,661	(13,517)
Total comprehensive income (loss)	36,469	(2,038)	78,284	53,249
Comprehensive (income) loss attributable to noncontrolling interest in the Operating Partnership	(175)	8	(355)	(253)
Comprehensive loss attributable to noncontrolling interest in consolidated subsidiary		210		609
Comprehensive income (loss) attributable to common shareholders/unitholders	36,294	(1,820)	77,929	53,605
Life Storage LP [Member]
Net income (loss)	35,667	(4,969)	75,623	66,766
Other comprehensive income (loss):
Effective portion of gain (loss) on derivatives net of reclassification to interest expense	802	2,931	2,661	(13,517)
Total comprehensive income (loss)	36,469	(2,038)	78,284	53,249
Comprehensive (income) loss attributable to noncontrolling interest in the Operating Partnership	(175)	8	(355)	(253)
Comprehensive loss attributable to noncontrolling interest in consolidated subsidiary		210		609
Comprehensive income (loss) attributable to common shareholders/unitholders	$ 36,294	$ (1,820)	$ 77,929	$ 53,605

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating Activities
Net income	$ 75,623	$ 66,766
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	101,896	76,082
Amortization of debt issuance costs and bond discount	2,496	8,858
Gain on sale of storage facilities		(15,270)
Equity in income of joint ventures	(2,259)	(2,795)
Distributions from unconsolidated joint ventures	5,071	3,875
Non-vested stock earned	4,905	5,583
Stock option expense	11	85
Deferred income taxes	(2,382)
Changes in assets and liabilities (excluding the effects of acquisitions):
Accounts receivable	(1,636)	4,308
Prepaid expenses	(2,821)	(1,080)
Receipts from joint ventures	354	182
Accounts payable and other liabilities	(618)	5,787
Deferred revenue	(204)	(3,012)
Net cash provided by operating activities	180,436	149,369
Investing Activities
Acquisitions of storage facilities, net of cash acquired	(9,576)	(1,738,538)
Improvements, equipment additions, and construction in progress	(65,978)	(44,441)
Net proceeds from the sale of real estate	1,994	34,074
Investment in unconsolidated joint ventures	(69,786)	(5,336)
Property deposit		(759)
Net cash used in investing activities	(143,346)	(1,755,000)
Financing Activities
Net proceeds from sale of common stock/partnership units	15,633	944,872
Purchase of outstanding shares/units	(8,234)
Proceeds from line of credit	233,000	1,059,000
Repayments of line of credit	(157,000)	(898,000)
Proceeds from term notes, net of discount		796,682
Repayment of term note		(150,000)
Debt issuance costs		(15,253)
Settlement of forward starting interest rate swaps		(9,166)
Dividends paid - common stock	(137,174)	(112,688)
Distributions to noncontrolling interest holders	(641)	(557)
Mortgage principal payments	(263)	(145)
Net cash (used in) provided by financing activities	(54,679)	1,614,745
Net (decrease) increase in cash	(17,589)	9,114
Cash at beginning of period	23,685	7,032
Cash at end of period	6,096	16,146
Supplemental cash flow information
Cash paid for interest, net of interest capitalized	52,633	31,489
Cash paid for income taxes, net of refunds	1,296	911
Life Storage LP [Member]
Operating Activities
Net income	75,623	66,766
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	101,896	76,082
Amortization of debt issuance costs and bond discount	2,496	8,858
Gain on sale of storage facilities		(15,270)
Equity in income of joint ventures	(2,259)	(2,795)
Distributions from unconsolidated joint ventures	5,071	3,875
Non-vested stock earned	4,905	5,583
Stock option expense	11	85
Deferred income taxes	(2,382)
Changes in assets and liabilities (excluding the effects of acquisitions):
Accounts receivable	(1,636)	4,308
Prepaid expenses	(2,821)	(1,080)
Receipts from joint ventures	354	182
Accounts payable and other liabilities	(618)	5,787
Deferred revenue	(204)	(3,012)
Net cash provided by operating activities	180,436	149,369
Investing Activities
Acquisitions of storage facilities, net of cash acquired	(9,576)	(1,738,538)
Improvements, equipment additions, and construction in progress	(65,978)	(44,441)
Net proceeds from the sale of real estate	1,994	34,074
Investment in unconsolidated joint ventures	(69,786)	(5,336)
Property deposit		(759)
Net cash used in investing activities	(143,346)	(1,755,000)
Financing Activities
Net proceeds from sale of common stock/partnership units	15,633	944,872
Purchase of outstanding shares/units	(8,234)
Proceeds from line of credit	233,000	1,059,000
Repayments of line of credit	(157,000)	(898,000)
Proceeds from term notes, net of discount		796,682
Repayment of term note		(150,000)
Debt issuance costs		(15,253)
Settlement of forward starting interest rate swaps		(9,166)
Distributions to unitholders	(137,174)	(112,688)
Distributions to noncontrolling interest holders	(641)	(557)
Mortgage principal payments	(263)	(145)
Net cash (used in) provided by financing activities	(54,679)	1,614,745
Net (decrease) increase in cash	(17,589)	9,114
Cash at beginning of period	23,685	7,032
Cash at end of period	6,096	16,146
Supplemental cash flow information
Cash paid for income taxes, net of refunds	1,296	911
Cash paid for interest, net of interest capitalized	$ 52,633	$ 31,489

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation	1. BASIS OF PRESENTATION The accompanying unaudited financial statements of Life Storage, Inc. (the “Parent Company”) and Life Storage LP (the “Operating Partnership”) have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Operating results for the nine month period ended September 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017.

Organization

Organization	9 Months Ended
	Sep. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization	2. ORGANIZATION The Parent Company operates as a self-administered and self-managed real estate investment trust (a “REIT”) that owns and operates self-storage facilities throughout the United States. All of the Parent Company’s assets are owned by, and all its operations are conducted through, the Operating Partnership. Life Storage Holdings, Inc., a wholly-owned subsidiary of the Parent Company (“Holdings”), is the sole general partner of the Operating Partnership; the Parent Company is a limited partner of the Operating Partnership, and, through its ownership of Holdings and its limited partnership interest, controls the operations of the Operating Partnership, holding a 99.5% ownership interest therein as of September 30, 2017. The remaining ownership interests in the Operating Partnership (the “Units”) are held by certain former owners of assets acquired by the Operating Partnership. The Parent Company, the Operating Partnership and their consolidated subsidiaries are collectively referred to in this report as the “Company.” In addition, terms such as “we,” “us,” or “our” used in this report may refer to the Company, the Parent Company and/or the Operating Partnership. At September 30, 2017, we had an ownership interest in, and/or managed 704 self-storage properties in 29 states under the name Life Storage ® We consolidate all wholly-owned subsidiaries. Partially owned subsidiaries and joint ventures are consolidated when we control the entity. Our consolidated financial statements include the accounts of the Parent Company, the Operating Partnership, Life Storage Solutions, LLC (the Parent Company’s taxable REIT subsidiary), Warehouse Anywhere LLC (an entity owned 60% by Life Storage Solutions, LLC), and all other wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated. Investments in joint ventures that we do not control but for which we have significant influence over are accounted for using the equity method. Included in the Parent Company’s consolidated balance sheets are noncontrolling redeemable Operating Partnership Units and included in the Operating Partnership’s consolidated balance sheets are limited partners’ redeemable capital interest at redemption value. These interests are presented in the “mezzanine” section of the consolidated balance sheet because they do not meet the functional definition of a liability or equity under current accounting literature. These represent the outside ownership interests of the limited partners in the Operating Partnership. At September 30, 2017 and December 31, 2016, there were 217,481 noncontrolling redeemable Operating Partnership Units outstanding. These unitholders are entitled to receive distributions per unit equivalent to the dividends declared per share on the Parent Company’s common stock. The Operating Partnership is obligated to redeem each of these limited partnership units in the Operating Partnership at the request of the holder thereof for cash equal to the fair market value of a share of the Parent Company’s common stock based on quoted market prices, at the time of such redemption, provided that the Company at its option may elect to acquire any such Unit presented for redemption for one common share or cash. The Company accounts for these noncontrolling redeemable Operating Partnership Units under the provisions of Accounting Standards Codification (ASC) Topic 480-10-S99. The application of the ASC Topic 480-10-S99 accounting model requires the noncontrolling interest to follow normal noncontrolling interest accounting and then be marked to redemption value at the end of each reporting period if higher (but never adjusted below that normal noncontrolling interest accounting amount). The offset to the adjustment to the carrying amount of the noncontrolling interests is reflected in the Company’s dividends in excess of net income and in the Operating Partnership’s general partner and limited partners capital balances. Accordingly, in the accompanying consolidated balance sheets, noncontrolling interests are reflected at redemption value at September 30, 2017 and December 31, 2016, equal to the number of noncontrolling interest units outstanding multiplied by the fair market value of the Parent Company’s common stock at that date. Redemption value exceeded the value determined under the Company’s historical basis of accounting at those dates. The following is a reconciliation of the Parent Company’s noncontrolling redeemable Operating Partnership Units and the Operating Partnership’s limited partners’ redeemable capital interest for the period: (dollars in thousands) Nine Months Ended September 30, 2017 Beginning balance $ 18,091 Net income attributable to noncontrolling interest in the Operating Partnership 343 Distributions (641 ) Adjustment to redemption value (155 ) Ending balance $ 17,638 During 2017, approximately 23% and 13% of the Company’s revenue is derived from stores in the states of Texas and Florida, respectively.

Stock Based Compensation

Stock Based Compensation	9 Months Ended
	Sep. 30, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Based Compensation	3. STOCK BASED COMPENSATION The Company accounts for stock-based compensation under the provisions of ASC Topic 718, “ Compensation - Stock Compensation For awards with graded vesting, compensation cost is recognized on a straight-line basis over the related vesting period. For the three months ended September 30, 2017 and 2016, the Company recorded compensation expense (included in general and administrative expense) of $4,000 and $4,000, respectively, related to stock options and $1,659,000 and $1,758,000, respectively, related to amortization of non-vested stock grants and performance-based awards. For the nine months ended September 30, 2017 and 2016, the Company recorded compensation expense of $11,000 and $85,000, respectively, related to stock options and $4,905,000 and $5,515,000, respectively, related to amortization of non-vested stock grants and performance-based awards. No stock options were exercised by employees and directors during the nine months ended September 30, 2017 and 2016. During the three months ended September 30, 2017 and 2016, 19,537 and 29,205 shares of non-vested stock, respectively, vested. During the nine months ended September 30, 2017 and 2016, 66,565 and 40,086 shares of non-vested stock, respectively, vested. During the nine months ended September 30, 2017, the Company issued 34,240 shares of non-vested stock to employees which vest over one, five or eight years. The fair market value on the date of grant of the non-vested stock issued during the nine months ended September 30, 2017 ranged from $74.30 to $86.78, resulting in an aggregate fair value of $2.9 million. During the nine months ended September 30, 2017, the Company granted performance-based awards that entitle the recipients to earn up to 17,888 shares if certain performance criteria are achieved over a three year period. The Company estimated the aggregate fair value of the awards on the grant date to be $0.8 million.

Investment in Storage Facilitie

Investment in Storage Facilities and Intangible Assets	9 Months Ended
	Sep. 30, 2017
Real Estate [Abstract]
Investment in Storage Facilities and Intangible Assets	4. INVESTMENT IN STORAGE FACILITIES AND INTANGIBLE ASSETS The following summarizes our activity in storage facilities during the nine months ended September 30, 2017: (dollars in thousands) Cost: Beginning balance $ 4,243,308 Acquisition of storage facilities 10,089 Improvements and equipment additions 67,026 Additions to consolidated subsidiary 113 Net decrease in construction in progress (1,784 ) Dispositions (12,357 ) Ending balance $ 4,306,395 Accumulated Depreciation: Beginning balance $ 535,704 Additions during the period 77,105 Dispositions (10,955 ) Ending balance $ 601,854 The Company acquired one self-storage facility during the nine months ended September 30, 2017. The acquisition of this facility was accounted for as an asset acquisition (see Note 14 for further discussion of the Company’s adoption of the accounting guidance under ASU 2017-01 as of January 1, 2017). The cost of this facility, including closing costs, was assigned to land, building, equipment and improvements based upon their relative fair values. The purchase price of the facility acquired in 2017 has been assigned as follows: (dollars in thousands) Consideration paid States Number of Properties Date of Acquisition Purchase Price Cash Paid Value of Operating Partnership Units Issued Mortgage Assumed Net Other Liabilities (Assets) Assumed Land Building, Equipment, and Improvements In-Place Customers Leases Closing Costs Expensed IL 1 2/23/17 $ 10,089 $ 10,076 $ — $ — $ 13 $ 771 $ 9,318 $ — $ — The facility acquired was purchased from an unrelated third party. The operating results of the facility acquired have been included in the Company’s operations since the acquisition date. The $10.1 million of cash paid for the facility includes $0.5 million of deposits that were paid in 2015 when this facility originally went under contract. This amount is excluded from total cash payments for the acquisition of storage facilities in the consolidated statement of cash flows. Non-cash investing activities during the nine months ended September 30, 2017 include the assumption of net other liabilities of $13,000. Non-cash investing activities during nine months ended September 30, 2016 include the issuance of $7.8 million in Operating Partnership Units, the assumption of two mortgages with fair values totaling $8.3 million, and the assumption of net other liabilities of $7.3 million. The Company measures the fair value of in-place customer lease intangible assets based on the Company’s experience with customer turnover and the cost to replace the in-place leases. The Company amortizes in-place customer leases on a straight-line basis over 12 months (the estimated future benefit period). The Company measures the value of trade names, which have an indefinite life and are not amortized, by calculating discounted cash flows utilizing the relief from royalty method. In-place customer leases are included in other assets on the Company’s consolidated balance sheets as follows: (Dollars in thousands) Sep. 30, 2017 Dec. 31, 2016 In-place customer leases $ 75,611 $ 75,611 Accumulated amortization (75,573 ) (50,782 ) Net carrying value at the end of period $ 38 $ 24,829 Amortization expense related to in-place customer leases was $0.1 million and $13.5 million for the three months ended September 30, 2017 and 2016, respectively, and was $24.8 million and $16.5 million for the nine months ended September 30, 2017 and 2016, respectively. The Company expects to record $24.8 million and $0 of amortization expense for the years ended December 31, 2017 and 2018, respectively. Change in Useful Life Estimates The change in name of the Company’s storage facilities from Uncle Bob’s Self Storage ® ® ® As part of the Company’s capital improvement efforts during 2017, buildings at certain self-storage facilities were identified for replacement. As a result of the decision to replace these buildings, the Company reassessed the estimated useful lives of the then existing buildings. This useful life reassessment resulted in an increase in depreciation expense of approximately $2.0 million and $3.6 million, respectively, during the three and nine month periods ended September 30, 2017. The Company estimates that the change in estimated useful lives of buildings identified for replacement as of September 30, 2017 will have minimal additional impact on depreciation expense during the remainder of 2017. The accelerated depreciation resulting from the events discussed above reduced both basic and diluted earnings per share/unit by approximately $0.04 and $0.09, respectively, for the three and nine month periods ended September 30, 2017.

Unsecured Line of Credit and Te

Unsecured Line of Credit and Term Notes	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Unsecured Line of Credit and Term Notes	5. UNSECURED LINE OF CREDIT AND TERM NOTES Borrowings outstanding on our unsecured line of credit and term notes are as follows: (Dollars in thousands) Sep. 30, 2017 Dec. 31, 2016 Revolving line of credit borrowings $ 329,000 $ 253,000 Term note due June 4, 2020 325,000 325,000 Term note due August 5, 2021 100,000 100,000 Term note due April 8, 2024 175,000 175,000 Senior term note due July 1, 2026 600,000 600,000 Term note due July 21, 2028 200,000 200,000 Total term note principal balance outstanding $ 1,400,000 $ 1,400,000 Less: unamortized debt issuance costs (8,289 ) (9,323 ) Less: unamortized senior term note discount (2,903 ) (3,152 ) Term notes payable $ 1,388,808 $ 1,387,525 In January 2016, the Company exercised the expansion feature on its existing amended unsecured credit agreement and increased the revolving credit limit from $300 million to $500 million. The interest rate on the revolving credit facility bears interest at a variable annual rate equal to LIBOR plus a margin based on the Company’s credit rating (at September 30, 2017 the margin is 1.10%), and requires an annual 0.15% facility fee. The Company’s unsecured credit agreement also includes a $325 million unsecured term note maturing June 4, 2020, with the term note bearing interest at LIBOR plus a margin based on the Company’s credit rating (at September 30, 2017 the margin is 1.15%). The interest rate at September 30, 2017 on the Company’s line of credit was approximately 2.34% (1.79% at December 31, 2016). At September 30, 2017, there was $171 million available on the unsecured revolving line of credit. The revolving line of credit has a maturity date of December 10, 2019. On June 20, 2016, the Operating Partnership issued $600 million in aggregate principal amount of 3.50% unsecured senior notes due July 1, 2026 (the “2026 Senior Notes”). The 2026 Senior Notes were issued at a 0.553% discount to par value. Interest on the 2026 Senior Notes is payable semi-annually in arrears on January 1 and July 1, beginning on January 1, 2017. The 2026 Senior Notes are fully and unconditionally guaranteed by the Parent Company. Proceeds received upon issuance, net of discount to par of $3.3 million and underwriting discount and other offering expenses of $5.5 million, totaled $591.2 million. The indenture under which the 2026 Senior Notes were issued restricts the ability of the Company and its subsidiaries to incur debt unless the Company and its consolidated subsidiaries comply with a leverage ratio not to exceed 60% and an interest coverage ratio of more than 1.5:1 on all outstanding debt, after giving effect to the incurrence of the debt. The indenture also restricts the ability of the Company and its subsidiaries to incur secured debt unless the Company and its consolidated subsidiaries comply with a secured debt leverage ratio not to exceed 40% after giving effect to the incurrence of the debt. The indenture also contains other financial and customary covenants, including a covenant not to own unencumbered assets with a value less than 150% of the unsecured indebtedness of the Company and its consolidated subsidiaries. The Company was in compliance with all of the financial covenants under the 2026 Senior Notes as of September 30, 2017. On July 21, 2016, the Company entered into a $200 million term note maturing July 21, 2028 bearing interest at a fixed rate of 3.67%. On April 8, 2014, the Company entered into a $175 million term note maturing April 8, 2024 bearing interest at a fixed rate of 4.533%. The interest rate on the term note increases to 6.283% if the Company is not rated by at least one rating agency or if the Company’s credit rating is downgraded. In 2011, the Company entered into a $100 million term note maturing August 5, 2021 bearing interest at a fixed rate of 5.54%. The interest rate on the term note increases to 7.29% if the notes are not rated by at least one rating agency, the credit rating on the notes is downgraded or if the Company’s credit rating is downgraded. The line of credit and term notes require the Company to meet certain financial covenants, measured on a quarterly basis, including prescribed leverage, fixed charge coverage, minimum net worth, limitations on additional indebtedness and limitations on dividend payouts. The Company was in compliance with its debt covenants at September 30, 2017. We believe that if operating results remain consistent with historical levels and levels of other debt and liabilities remain consistent with amounts outstanding at September 30, 2017, the entire availability on the line of credit could be drawn without violating our debt covenants. The Company’s fixed rate term notes contain a provision that allows for the noteholders to call the debt upon a change of control of the Company at an amount that includes a make whole premium based on rates in effect on the date of the change of control. At this time no change in control is planned or anticipated. Deferred debt issuance costs and the discount on the 2026 Senior Notes are both presented as reductions of term notes in the accompanying consolidated balance sheets at September 30, 2017 and December 31, 2016. Amortization expense related to these deferred debt issuance costs was $0.5 million and $0.5 million for the three months ended September 30, 2017 and 2016, respectively, and $1.6 million and $1.2 million for the nine month period ended September 30, 2017 and 2016, respectively, and is included in interest expense in the consolidated statements of income.

Mortgages Payable and Debt Matu

Mortgages Payable and Debt Maturities	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Mortgages Payable and Debt Maturities	6. MORTGAGES PAYABLE AND DEBT MATURITIES Mortgages payable at September 30, 2017 and December 31, 2016 consist of the following: (dollars in thousands) Sep. 30, 2017 Dec. 31, 2016 4.98% mortgage note due January 1, 2021, secured by one self-storage facility with an aggregate net book value of $9.7 million, principal and interest paid monthly (effective interest rate 5.23%) $ 2,929 $ 2,966 4.065% mortgage note due April 1, 2023, secured by one self- storage facility with an aggregate net book value of $7.6 million, principal and interest paid monthly (effective interest rate 4.31%) 4,140 4,207 5.26% mortgage note due November 1, 2023, secured by one self-storage facility with an aggregate net book value of $8.0 million, principal and interest paid monthly (effective interest rate 5.57%) 3,955 4,002 5.99% mortgage note due May 1, 2026, secured by one self- storage facility with an aggregate net book value of $6.6 million, principal and interest paid monthly (effective interest rate 6.27%) 1,740 1,852 Total mortgages payable $ 12,764 $ 13,027 The table below summarizes the Company’s debt obligations and interest rate derivatives at September 30, 2017. The estimated fair value of financial instruments is subjective in nature and is dependent on a number of important assumptions, including discount rates and relevant comparable market information associated with each financial instrument. The fair value of the fixed rate term notes and mortgage notes were estimated by discounting the future cash flows using the current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining maturities. These assumptions are considered Level 2 inputs within the fair value hierarchy as described in Note 8. The carrying values of our variable rate debt instruments approximate their fair values as these debt instruments bear interest at current market rates that approximate market participant rates. This is considered a Level 2 input within the fair value hierarchy. The use of different market assumptions and estimation methodologies may have a material effect on the reported estimated fair value amounts. Accordingly, the estimates presented below are not necessarily indicative of the amounts the Company would realize in a current market exchange. Expected Maturity Date Including Discount (dollars in thousands) 2017 2018 2019 2020 2021 Thereafter Total Fair Value Line of credit - variable rate LIBOR + 1.10% (2.34% at September 30, 2017) — — $ 329,000 — — — $ 329,000 $ 329,000 Notes Payable: Term note - variable rate LIBOR+1.15% (2.38% at September 30, 2017) — — — $ 325,000 — — $ 325,000 $ 325,000 Term note - fixed rate 5.54% — — — — $ 100,000 — $ 100,000 $ 109,428 Term note - fixed rate 4.533% — — — — — $ 175,000 $ 175,000 $ 182,710 Term note - fixed rate 3.50% — — — — — $ 600,000 $ 600,000 $ 583,759 Term note - fixed rate 3.67% — — — — — $ 200,000 $ 200,000 $ 191,932 Mortgage note - fixed rate 4.98% $ 13 $ 53 $ 56 $ 59 $ 2,748 — $ 2,929 $ 3,061 Mortgage note - fixed rate 4.065% $ 22 $ 92 $ 95 $ 99 $ 104 $ 3,728 $ 4,140 $ 4,190 Mortgage note - fixed rate 5.26% $ 16 $ 67 $ 71 $ 74 $ 78 $ 3,649 $ 3,955 $ 4,203 Mortgage note - fixed rate 5.99% $ 39 $ 160 $ 170 $ 181 $ 192 $ 998 $ 1,740 $ 1,867 Interest rate derivatives - liability — — — — — — — $ 10,923 Total $ 90 $ 372 $ 329,392 $ 325,413 $ 103,122 $ 983,375 $ 1,741,764

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2017
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	7. DERIVATIVE FINANCIAL INSTRUMENTS Interest rate swaps are used to adjust the proportion of total debt that is subject to variable interest rates. The interest rate swaps require the Company to pay an amount equal to a specific fixed rate of interest times a notional principal amount and to receive in return an amount equal to a variable rate of interest times the same notional amount. The notional amounts are not exchanged. Forward starting interest rate swaps are also used by the Company to hedge the risk of changes in the interest-related cash outflows associated with the potential issuance of long-term debt. No other cash payments are made unless the contract is terminated prior to its maturity, in which case the contract would likely be settled for an amount equal to its fair value. The Company enters into interest rate swaps with a number of major financial institutions to minimize counterparty credit risk. The interest rate swaps qualify and are designated as hedges of the amount of future cash flows related to interest payments on variable rate debt. Therefore, the interest rate swaps are recorded in the consolidated balance sheet at fair value and the related gains or losses are deferred in shareholders’ equity or partners’ capital as Accumulated Other Comprehensive Loss (“AOCL”). These deferred gains and losses are recognized in interest expense during the period or periods in which the related interest payments affect earnings. However, to the extent that the interest rate swaps are not perfectly effective in offsetting the change in value of the interest payments being hedged, the ineffective portion of these contracts is recognized in earnings immediately. Ineffectiveness was de minimis for the three and nine months ended September 30, 2017. The Company has interest rate swap agreements in effect at September 30, 2017 as detailed below to effectively convert a total of $325 million of variable-rate debt to fixed-rate debt. Notional Amount Effective Date Expiration Date Fixed Rate Paid Floating Rate Received $125 Million 9/1/2011 8/1/18 2.3700 % 1 month LIBOR $100 Million 12/30/11 12/29/17 1.6125 % 1 month LIBOR $100 Million 9/4/13 9/4/18 1.3710 % 1 month LIBOR $100 Million 12/29/17 11/29/19 3.9680 % 1 month LIBOR $125 Million 8/1/18 6/1/20 4.1930 % 1 month LIBOR In the fourth quarter of 2015, the Company entered into forward starting interest rate swap agreements with a total notional value of $50 million. In the first quarter of 2016, the Company entered into additional forward starting interest rate swap agreements with a total notional value of $100 million. These forward starting interest rate swap agreements were entered into to hedge the risk of changes in the interest-related cash flows associated with the potential issuance of fixed rate long-term debt. In conjunction with the issuance of the $600 million 2026 Senior Notes (see Note 5) in the second quarter of 2016, the Company settled the forward starting swap agreements for a loss of approximately $9.2 million. The loss was recorded as accumulated other comprehensive loss and is being amortized as additional interest expense over the ten-year term of the $600 million 2026 Senior Notes. Consistent with the Company’s accounting policy, the cash outflow related to the settlement of the forward starting swap agreements is reflected as a financing activity in the consolidated statements of cash flows. The interest rate swap agreements are the only derivative instruments, as defined by FASB ASC Topic 815 “ Derivatives and Hedging The Company’s agreements with its interest rate swap counterparties contain provisions pursuant to which the Company could be declared in default of its derivative obligations if the Company defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender. The interest rate swap agreements also incorporate other loan covenants of the Company. Failure to comply with the loan covenant provisions would result in the Company being in default on the interest rate swap agreements. As of September 30, 2017, the Company had not posted any collateral related to the interest rate swap agreements. If the Company had breached any of these provisions as of September 30, 2017, it could have been required to settle its obligations under the agreements at their net termination cost of $10.9 million. The changes in AOCL for the three and nine months ended September 30, 2017 and 2016 are summarized as follows: (dollars in thousands) Three Months Ended September 30, 2017 Three Months Ended September 30, 2016 Nine Months Ended September 30, 2017 Nine Months Ended September 30, 2016 Accumulated other comprehensive loss beginning of period $ (19,616 ) $ (30,863 ) $ (21,475 ) $ (14,415 ) Realized loss reclassified from accumulated other comprehensive loss to interest expense 758 1,398 2,835 3,755 Unrealized loss from changes in the fair value of the effective portion of the interest rate swaps 44 1,533 (174 ) (17,272 ) Income (loss) included in other comprehensive loss 802 2,931 2,661 (13,517 ) Accumulated other comprehensive loss end of period $ (18,814 ) $ (27,932 ) $ (18,814 ) $ (27,932 )

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	8. FAIR VALUE MEASUREMENTS The Company applies the provisions of ASC Topic 820 “ Fair Value Measurements and Disclosures Refer to Note 6 for presentation of the fair values of debt obligations which are disclosed at fair value on a recurring basis. The following table provides the liabilities carried at fair value measured on a recurring basis as of September 30, 2017 and December 31, 2016 (in thousands): Asset (Liability) Level 1 Level 2 Level 3 September 30, 2017 Interest rate swaps $ (10,923 ) — $ (10,923 ) — December 31, 2016 Interest rate swaps $ (13,015 ) — $ (13,015 ) — Interest rate swaps are over the counter securities with no quoted readily available Level 1 inputs, and therefore are measured at fair value using inputs that are directly observable in active markets and are classified within Level 2 of the valuation hierarchy, using the income approach.

Investment in Joint Ventures

Investment in Joint Ventures	9 Months Ended
	Sep. 30, 2017
Equity Method Investments And Joint Ventures [Abstract]
Investment in Joint Ventures	9. INVESTMENT IN JOINT VENTURES A summary of the Company’s unconsolidated joint ventures is as follows: Venture Number of Properties Company common ownership interest Carrying value of investment at Sep. 30, 2017 Carrying value of investment at Dec. 31, 2016 Sovran HHF Storage Holdings LLC (“Sovran HHF”) 1 57 20 % $85.5 million $43.8 million Sovran HHF Storage Holdings II LLC (“Sovran HHF II”) 2 30 15 % $13.4 million $13.5 million 191 III Holdings LLC (“191 III”) 3 6 20 % $9.6 million $0.7 million Life Storage-SERS Storage LLC (“SERS”) 4 3 20 % $3.6 million N/A Iskalo Office Holdings, LLC (“Iskalo”) 5 N/A 49 % ($0.4 million) ($0.4 million) Urban Box Coralway Storage, LLC (“Urban Box”) 6 1 85 % $4.1 million $4.1 million SNL/Orix 1200 McDonald Ave., LLC (“McDonald”) 7 1 5 % $2.7 million $2.7 million SNL Orix Merrick, LLC (“Merrick”) 8 1 5 % $2.5 million $2.5 million Review Avenue Partners, LLC (“RAP”) 9 1 40 % $11.7 million N/A N 32nd Street Self Storage, LLC (“N32”) 10 1 46 % $1.3 million N/A 1 2 3 4 5 6 7 8 9 10 nd Based on the facts and circumstances of each of the Company’s joint ventures, the Company has determined that none of the joint ventures are a variable interest entity (VIE) in accordance with ASC 810, Consolidation The carrying values of the Company’s investments in joint ventures are assessed for other-than-temporary impairment on a periodic basis and no such impairments have been recorded on any of the Company’s investments in joint ventures. The Company earns management and/or call center fees ranging from 6% to 7% of joint venture gross revenues as manager of HHF, HHF II, 191 III, SERS, and RAP. These fees, which are included in other operating income in the consolidated statements of operations, totaled $1.9 million and $1.3 million for the three months ended September 30, 2017 and 2016, respectively, and $4.8 million and $3.8 million for the nine months ended September 30, 2017 and 2016, respectively. The Company will also earn management fees upon commencement of the operation of storage facilities owned by Urban Box, McDonald, Merrick and N32. The Company’s share of the unconsolidated joint ventures’ income (loss) is as follows: (dollars in thousands) Venture Three Months Ended September 30, 2017 Three Months Ended September 30, 2016 Nine Months Ended September 30, 2017 Nine Months Ended September 30, 2016 Sovran HHF $ 588 $ 485 $ 1,750 $ 1,563 Sovran HHF II 398 352 1,100 1,059 191 III (14 ) — 12 — SERS (43 ) — (43 ) — Urban Box — — — 15 RAP (248 ) — (749 ) — Iskalo 71 45 189 158 $ 752 $ 882 $ 2,259 $ 2,795 A summary of the unconsolidated joint ventures’ financial statements as of and for the nine months ended September 30, 2017 is as follows: (dollars in thousands) Balance Sheet Data: Investment in storage facilities, net $ 1,074,003 Investment in office building, net 4,872 Other assets 20,534 Total Assets $ 1,099,409 Due to the Company $ 869 Mortgages payable 455,676 Other liabilities 14,001 Total Liabilities $ 470,546 Unaffiliated partners’ equity 495,003 Company equity 133,860 Total Partners’ Equity 628,863 Total Liabilities and Partners’ Equity $ 1,099,409 Income Statement Data: Total revenues $ 68,841 Property operating expenses (23,075 ) Administrative, management and call center fees (5,829 ) Depreciation and amortization of customer list (14,684 ) Amortization of financing fees (579 ) Income tax expense (201 ) Interest expense (10,033 ) Net income $ 14,440 The Company does not guarantee the debt of any of its equity method investees. We do not expect to have material future cash outlays relating to these joint ventures outside our share of capital for future acquisitions of properties.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	10. INCOME TAXES The Company qualifies as a REIT under the Internal Revenue Code of 1986, as amended, and will generally not be subject to corporate income taxes to the extent it distributes its taxable income to its shareholders and complies with certain other requirements. The Company has elected to treat one of its subsidiaries as a taxable REIT subsidiary. In general, the Company’s taxable REIT subsidiary may perform additional services for tenants and generally may engage in certain real estate or non-real estate related business. A taxable REIT subsidiary is subject to corporate federal and state income taxes. Deferred tax assets and liabilities are determined based on differences between financial reporting and tax bases of assets and liabilities. The Company recorded federal and state income tax expense of $0.9 million and $0.2 million for the three months ended September 30, 2017 and 2016. The Company recorded federal and state income tax benefit of $1.3 million for the nine months ended September 30, 2017 and the Company recorded federal and state income tax expense of $0.9 million for the nine months ended September 30, 2016. At September 30, 2017 and 2016, there were no material unrecognized tax benefits. Interest and penalties relating to uncertain tax positions will be recognized in income tax expense when incurred. As of September 30, 2017 and 2016, the Company had no interest or penalties related to uncertain tax positions. Net income taxes payable at September 30, 2017 and December 31, 2016 and the net deferred tax liability of our taxable REIT subsidiary at December 31, 2016 are classified within accounts payable and accrued liabilities in the consolidated balance sheets. As of September 30, 2017, the Company’s taxable REIT subsidiary has a deferred tax liability of $2.9 million and deferred tax assets totaling $4.6 million. The net deferred tax asset of our taxable REIT subsidiary at September 30, 2017 is included in other assets in the consolidated balance sheets. The tax years 2013-2016 remain open to examination by the major taxing jurisdictions to which the Company is subject.

Earnings Per Share and Earnings

Earnings Per Share and Earnings Per Unit	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Share and Earnings Per Unit	11. EARNINGS PER SHARE AND EARNINGS PER UNIT The Company reports earnings per share and earnings per unit data in accordance ASC Topic 260, “ Earnings Per Share The following table sets forth the computation of basic and diluted earnings per common share utilizing the two-class method. Earnings Per Share (in thousands except per share data) Three Months Ended Sep. 30, 2017 Three Months Ended Sep. 30, 2016 Nine Months Ended Sep. 30, 2017 Nine Months Ended Sep. 30, 2016 Numerator: Net income (loss) attributable to common shareholders $ 35,496 $ (4,738 ) $ 75,280 $ 67,058 Denominator: Denominator for basic earnings (loss) per share – weighted average shares 46,416 46,139 46,362 42,177 Effect of Dilutive Securities: Stock options and non-vested stock 104 — 110 238 Denominator for diluted earnings (loss) per share – adjusted weighted average shares and assumed conversion 46,520 46,139 46,472 42,415 Basic earnings (loss) per common share attributable to common shareholders $ 0.76 $ (0.10 ) $ 1.62 $ 1.59 Diluted earnings (loss) per common share attributable to common shareholders $ 0.76 $ (0.10 ) $ 1.62 $ 1.58 Earnings Per Unit The following table sets forth the computation of basic and diluted earnings per common unit utilizing the two-class method. (in thousands except per unit data) Three Months Ended Sep. 30, 2017 Three Months Ended Sep. 30, 2016 Nine Months Ended Sep. 30, 2017 Nine Months Ended Sep. 30, 2016 Numerator: Net income (loss) attributable to common unitholders $ 35,496 $ (4,738 ) $ 75,280 $ 67,058 Denominator: Denominator for basic earnings (loss) per unit – weighted average units 46,416 46,139 46,362 42,177 Effect of Dilutive Securities: Stock options and non-vested stock 104 — 110 238 Denominator for diluted earnings (loss) per unit – adjusted weighted average units and assumed conversion 46,520 46,139 46,472 42,415 Basic earnings (loss) per common unit attributable to common unitholders $ 0.76 $ (0.10 ) $ 1.62 $ 1.59 Diluted earnings (loss) per common unit attributable to common unitholders $ 0.76 $ (0.10 ) $ 1.62 $ 1.58 Not included in the effect of dilutive securities above for both earnings per share and earnings per unit are 17,500 stock options and 133,179 unvested restricted shares for the three months ended September 30, 2017, and 270,298 unvested restricted shares for the three months ended September 30, 2016, because their effect would be antidilutive. Not included in the effect of dilutive securities above are 14,667 stock options and 139,107 unvested restricted shares for the nine months ended September 30, 2017, and 110,757 unvested restricted shares for the nine months ended September 30, 2016, because their effect would be antidilutive.

Shareholders' Equity

Shareholders' Equity	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Shareholders' Equity	12. SHAREHOLDERS’ EQUITY The following is a reconciliation of the changes in the Parent Company’s total shareholders’ equity for the period: (dollars in thousands) Nine Months Ended September 30, 2017 Beginning balance of total shareholders’ equity $ 2,088,494 Net proceeds from the issuance of common stock through Dividend Reinvestment Plan 15,633 Purchase of outstanding shares (8,234 ) Earned portion of non-vested stock 4,905 Stock option expense 11 Deferred compensation - directors — Adjustment to redemption value on noncontrolling redeemable Operating Partnership units 155 Net income attributable to common shareholders 75,280 Amortization of terminated hedge included in AOCL 688 Change in fair value of derivatives 1,973 Dividends (136,796 ) Ending balance of total shareholders’ equity $ 2,042,109 On January 20, 2016, the Company completed the public offering of 2,645,000 shares of its common stock at $105.75 per share. Net proceeds to the Company after deducting underwriting discounts and commissions and offering expenses were approximately $269.7 million. On May 25, 2016, the Company completed the public offering of 6,900,000 shares of its common stock at $100.00 per share. Net proceeds to the Company after deducting underwriting discounts and commissions and offering expenses were approximately $665.4 million. Until May 2017, the Company had maintained a continuous equity offering program (“Equity Program”) with Wells Fargo Securities, LLC, Jefferies LLC, SunTrust Robinson Humphrey, Inc., Piper Jaffray & Co., HSBC Securities (USA) Inc., and BB&T Capital Markets, a division of BB&T Securities, LLC, pursuant to which the Company could sell up to $225 million in aggregate offering price of shares of the Company’s common stock. The Equity Program expired in May 2017. During the nine months ended September 30, 2017 and 2016, the Company did not issue any shares of common stock under the Equity Program. On August 2, 2017, the Company’s Board of Directors authorized the repurchase of up to $200 million of the Company’s outstanding common shares (“Buyback Program”). The Buyback Program allows the Company to purchase shares of its common stock in accordance with applicable securities laws on the open market, through privately negotiated transactions, or through other methods of acquiring shares. The Buyback Program may be suspended or discontinued at any time. During 2017, the Company repurchased 112,554 of the Company’s outstanding common shares for $8.2 million under the Buyback Program, resulting in a weighted average purchase price of $73.16 per share. In 2013, the Company implemented a Dividend Reinvestment Plan. The Company issued 199,809 and 94,050 shares under the plan during the nine months ended September 30, 2017 and 2016, respectively. On August 2, 2017, the Company’s Board of Directors suspended the Dividend Reinvestment Plan.

Partners' Capital

Partners' Capital	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Partners' Capital	13. PARTNERS’ CAPITAL The following is a reconciliation of the changes in total partners’ capital for the period: (dollars in thousands) Nine Months Ended September 30, 2017 Beginning balance of total controlling partners’ capital $ 2,088,494 Net proceeds from the issuance of partnership units through Dividend Reinvestment Plan 15,633 Purchase of outstanding units (8,234 ) Earned portion of non-vested stock 4,905 Stock option expense 11 Deferred compensation - directors — Adjustment to redemption value on limited partners’ redeemable capital interests 155 Net income attributable to common unitholders 75,280 Amortization of terminated hedge included in AOCL 688 Change in fair value of derivatives 1,973 Distributions (136,796 ) Ending balance of total controlling partners’ capital $ 2,042,109

Recent Accounting Pronouncement

Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2017
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Pronouncements	14. RECENT ACCOUNTING PRONOUNCEMENTS In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers,” which supersedes the revenue recognition requirements in “Revenue Recognition (Topic 605),” and requires an entity to recognize revenue in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. ASU 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017. The Company has the option to apply the provisions of ASU 2014-09 either retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initially applying the new guidance recognized at the date of initial application (the modified retrospective transition method). We are currently evaluating the effect of adopting ASU 2014-09 on our financial statements and related disclosures. We anticipate electing to adopt the standard using the modified retrospective transition method as of January 1, 2018. We are also in the process of assessing which of our operating revenue streams will be impacted by the adoption of the new standard. Leases are specifically excluded from the scope of ASU 2014-09, therefore the Company does not anticipate that adoption of the new standard will have any impact on the timing or amounts of the Company’s rental revenue from customers which is over 90% of the Company’s total operating revenues. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)”. This guidance revises existing practice related to accounting for leases under Accounting Standards Codification Topic 840 Leases In March 2016, the FASB issued ASU 2016-06, “Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments”. ASU 2016-06 simplifies the embedded derivative analysis for debt instruments containing contingent call or put options by removing the requirement to assess whether a contingent event is related to interest rates or credit risks. ASU 2016-06 is effective for fiscal years, and interim reporting periods within those fiscal years, beginning after December 15, 2016. The implementation of this update did not result in any changes to our consolidated financial statements. In March 2016, the FASB issued ASU 2016-07, “Investments - Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting”. ASU 2016-07 eliminates the requirement that when an investment qualifies for use of the equity method as a result of an increase in the level of ownership interest or degree of influence, an adjustment must be made to the investment, results of operations, and retained earnings retroactively on a step-by-step basis as if the equity method had been in effect during all previous periods that the investment had been held. ASU 2016-07 is effective for fiscal years, and interim reporting periods within those fiscal years, beginning after December 15, 2016. The implementation of this update did not result in any changes to our consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, “Improvements to Employee Share-Based Payment Accounting” as part of its simplification initiative, which involves several aspects of accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. ASU 2016-09 is effective for fiscal years, and interim reporting periods within those fiscal years, beginning after December 15, 2016. The implementation of this update did not result in any changes to our consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a Consensus of the Emerging Issues Task Force)” in an effort to reduce existing diversity in practice related to the classification of certain cash receipts and cash payments on the statements of cash flows. The guidance addresses the classification of cash flows related to, among other things, distributions received from equity method investees. The amendments in this update are effective for annual periods beginning after December 15, 2017, and interim periods within those annual periods. ASU 2016-15 is not expected to have a material impact on the Company’s consolidated financial statements. In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230): Restricted Cash (a Consensus of the Emerging Issues Task Force)” which requires restricted cash and restricted cash equivalents to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The amendments in this update are effective for annual periods beginning after December 15, 2017 and interim periods within those fiscal years. Early adoption of this update is permitted. Other than modifications to the statement of cash flows, the adoption of ASU 2016-18 is not expected to have a material impact on the Company’s consolidated financial statements. In January 2017, the FASB issued ASU 2017-01, “Business Combinations (Topic 805): Clarifying the Definition of a Business” which is intended to assist entities with evaluating whether a set of transferred assets and activities is a business. The amendments in this update are effective for annual periods beginning after December 15, 2017 and interim periods within those fiscal years. Early adoption of this update is permitted and the Company adopted this update effective January 1, 2017. The adoption of ASU 2017-01 is expected to have potential impact on the accounting treatment of properties acquired subsequent to the adoption date. Property acquisitions treated as business combinations under current guidance may no longer be treated as business combinations subsequent to the adoption of ASU 2017-01. To the extent that properties that we acquire do not meet the definition of a “business” under ASU 2017-01, future acquisitions of properties may be accounted for as asset acquisitions resulting in the capitalization of acquisition costs incurred in connection with these transactions and the allocation of the purchase price and related acquisition costs to the assets acquired based on their relative fair values. There were no properties acquired during the nine months ended September 30, 2017 that would have been accounted for as business combinations prior to the adoption of ASU 2017-01. In February 2017, the FASB issued ASU 2017-05, “Other Income – Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets” which clarifies the scope and application of ASC 610-20 on the sale or transfer of nonfinancial assets, including real estate, and in substance nonfinancial assets to noncustomers, including partial sales. The amendments in this update are effective for annual periods beginning after December 15, 2017, and interim periods within those annual periods. The Company has not yet completed its assessment of the impact that the adoption of ASU 2017-05 will have on its consolidated financial statements.

Commitment and Contingencies

Commitment and Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments And Contingencies Disclosure [Abstract]
Commitment and Contingencies	15. COMMITMENT AND CONTINGENCIES At September 30, 2017, the Company was under contract to acquire one self-storage facility for a purchase price of $12.4 million. The purchase of this facility is subject to customary conditions to closing, and there is no assurance that this facility will be acquired. On or about August 25, 2014, a putative class action was filed against the Company in the Superior Court of New Jersey Law Division Burlington County. The action seeks to obtain declaratory, injunctive and monetary relief for a class of consumers based upon alleged violations by the Company of various statutory laws. On October 17, 2014, the action was removed from the Superior Court of New Jersey Law Division Burlington County to the United States District Court for the District of New Jersey. The Company brought a motion to partially dismiss the complaint for failure to state a claim, and on July 16, 2015, the Company’s motion was granted in part and denied in part. On October 20, 2016, the complaint was amended to add additional claims. The parties have entered into a memorandum of understanding to settle all claims for an aggregate amount of $8.0 million and have jointly moved for preliminary judicial approval of the settlement in November 2017. The aggregate settlement amount of $8.0 million ($5.0 million after considering income tax impact) has been recorded as a liability of the Company. A portion of the settlement expense relates to self-storage facilities that are managed by the Company through its taxable REIT subsidiary. There is an income tax impact to the Company on that portion of the settlement expense as a result. The settlement is subject to approval by the court, a decision on which is expected later in 2017.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	16. SUBSEQUENT EVENTS On October 3, 2017, the Company declared a quarterly dividend of $1.00 per common share. The dividend was paid on October 26, 2017 to shareholders of record on October 13, 2017. The total dividend paid amounted to $46.5 million.

Recent Accounting Pronounceme23

Recent Accounting Pronouncements (Policies)	9 Months Ended
	Sep. 30, 2017
Accounting Changes And Error Corrections [Abstract]
Revenue from Contracts with Customers	In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers,” which supersedes the revenue recognition requirements in “Revenue Recognition (Topic 605),” and requires an entity to recognize revenue in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. ASU 2014-09 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017. The Company has the option to apply the provisions of ASU 2014-09 either retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initially applying the new guidance recognized at the date of initial application (the modified retrospective transition method). We are currently evaluating the effect of adopting ASU 2014-09 on our financial statements and related disclosures. We anticipate electing to adopt the standard using the modified retrospective transition method as of January 1, 2018. We are also in the process of assessing which of our operating revenue streams will be impacted by the adoption of the new standard. Leases are specifically excluded from the scope of ASU 2014-09, therefore the Company does not anticipate that adoption of the new standard will have any impact on the timing or amounts of the Company’s rental revenue from customers which is over 90% of the Company’s total operating revenues.
Leases	In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)”. This guidance revises existing practice related to accounting for leases under Accounting Standards Codification Topic 840 Leases
Derivatives and Hedging	In March 2016, the FASB issued ASU 2016-06, “Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments”. ASU 2016-06 simplifies the embedded derivative analysis for debt instruments containing contingent call or put options by removing the requirement to assess whether a contingent event is related to interest rates or credit risks. ASU 2016-06 is effective for fiscal years, and interim reporting periods within those fiscal years, beginning after December 15, 2016. The implementation of this update did not result in any changes to our consolidated financial statements.
Investments-Equity Method and Joint Ventures	In March 2016, the FASB issued ASU 2016-07, “Investments - Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting”. ASU 2016-07 eliminates the requirement that when an investment qualifies for use of the equity method as a result of an increase in the level of ownership interest or degree of influence, an adjustment must be made to the investment, results of operations, and retained earnings retroactively on a step-by-step basis as if the equity method had been in effect during all previous periods that the investment had been held. ASU 2016-07 is effective for fiscal years, and interim reporting periods within those fiscal years, beginning after December 15, 2016. The implementation of this update did not result in any changes to our consolidated financial statements.
Improvements to Employee Share-Based Payment Accounting	In March 2016, the FASB issued ASU 2016-09, “Improvements to Employee Share-Based Payment Accounting” as part of its simplification initiative, which involves several aspects of accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. ASU 2016-09 is effective for fiscal years, and interim reporting periods within those fiscal years, beginning after December 15, 2016. The implementation of this update did not result in any changes to our consolidated financial statements.
Statement of Cash Flows	In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a Consensus of the Emerging Issues Task Force)” in an effort to reduce existing diversity in practice related to the classification of certain cash receipts and cash payments on the statements of cash flows. The guidance addresses the classification of cash flows related to, among other things, distributions received from equity method investees. The amendments in this update are effective for annual periods beginning after December 15, 2017, and interim periods within those annual periods. ASU 2016-15 is not expected to have a material impact on the Company’s consolidated financial statements. In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230): Restricted Cash (a Consensus of the Emerging Issues Task Force)” which requires restricted cash and restricted cash equivalents to be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The amendments in this update are effective for annual periods beginning after December 15, 2017 and interim periods within those fiscal years. Early adoption of this update is permitted. Other than modifications to the statement of cash flows, the adoption of ASU 2016-18 is not expected to have a material impact on the Company’s consolidated financial statements.
Business Combinations	In January 2017, the FASB issued ASU 2017-01, “Business Combinations (Topic 805): Clarifying the Definition of a Business” which is intended to assist entities with evaluating whether a set of transferred assets and activities is a business. The amendments in this update are effective for annual periods beginning after December 15, 2017 and interim periods within those fiscal years. Early adoption of this update is permitted and the Company adopted this update effective January 1, 2017. The adoption of ASU 2017-01 is expected to have potential impact on the accounting treatment of properties acquired subsequent to the adoption date. Property acquisitions treated as business combinations under current guidance may no longer be treated as business combinations subsequent to the adoption of ASU 2017-01. To the extent that properties that we acquire do not meet the definition of a “business” under ASU 2017-01, future acquisitions of properties may be accounted for as asset acquisitions resulting in the capitalization of acquisition costs incurred in connection with these transactions and the allocation of the purchase price and related acquisition costs to the assets acquired based on their relative fair values. There were no properties acquired during the nine months ended September 30, 2017 that would have been accounted for as business combinations prior to the adoption of ASU 2017-01.
Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets	In February 2017, the FASB issued ASU 2017-05, “Other Income – Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets” which clarifies the scope and application of ASC 610-20 on the sale or transfer of nonfinancial assets, including real estate, and in substance nonfinancial assets to noncustomers, including partial sales. The amendments in this update are effective for annual periods beginning after December 15, 2017, and interim periods within those annual periods. The Company has not yet completed its assessment of the impact that the adoption of ASU 2017-05 will have on its consolidated financial statements.

Organization (Tables)

Organization (Tables)	9 Months Ended
	Sep. 30, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Summary of Reconciliation of Noncontrolling Interests	The following is a reconciliation of the Parent Company’s noncontrolling redeemable Operating Partnership Units and the Operating Partnership’s limited partners’ redeemable capital interest for the period: (dollars in thousands) Nine Months Ended September 30, 2017 Beginning balance $ 18,091 Net income attributable to noncontrolling interest in the Operating Partnership 343 Distributions (641 ) Adjustment to redemption value (155 ) Ending balance $ 17,638

Investment in Storage Facilit25

Investment in Storage Facilities and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2017
Real Estate [Abstract]
Summary of Activity in Storage Facilities	The following summarizes our activity in storage facilities during the nine months ended September 30, 2017: (dollars in thousands) Cost: Beginning balance $ 4,243,308 Acquisition of storage facilities 10,089 Improvements and equipment additions 67,026 Additions to consolidated subsidiary 113 Net decrease in construction in progress (1,784 ) Dispositions (12,357 ) Ending balance $ 4,306,395 Accumulated Depreciation: Beginning balance $ 535,704 Additions during the period 77,105 Dispositions (10,955 ) Ending balance $ 601,854
Schedule of Acquired Facilities and Purchase Price of Facilities	The purchase price of the facility acquired in 2017 has been assigned as follows: (dollars in thousands) Consideration paid States Number of Properties Date of Acquisition Purchase Price Cash Paid Value of Operating Partnership Units Issued Mortgage Assumed Net Other Liabilities (Assets) Assumed Land Building, Equipment, and Improvements In-Place Customers Leases Closing Costs Expensed IL 1 2/23/17 $ 10,089 $ 10,076 $ — $ — $ 13 $ 771 $ 9,318 $ — $ —
Schedule of Fair Value of In-Place Customer Lease Intangible Assets	In-place customer leases are included in other assets on the Company’s consolidated balance sheets as follows: (Dollars in thousands) Sep. 30, 2017 Dec. 31, 2016 In-place customer leases $ 75,611 $ 75,611 Accumulated amortization (75,573 ) (50,782 ) Net carrying value at the end of period $ 38 $ 24,829

Unsecured Line of Credit and 26

Unsecured Line of Credit and Term Notes (Tables)	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Borrowings Outstanding on Unsecured Line of Credit and Term Notes	Borrowings outstanding on our unsecured line of credit and term notes are as follows: (Dollars in thousands) Sep. 30, 2017 Dec. 31, 2016 Revolving line of credit borrowings $ 329,000 $ 253,000 Term note due June 4, 2020 325,000 325,000 Term note due August 5, 2021 100,000 100,000 Term note due April 8, 2024 175,000 175,000 Senior term note due July 1, 2026 600,000 600,000 Term note due July 21, 2028 200,000 200,000 Total term note principal balance outstanding $ 1,400,000 $ 1,400,000 Less: unamortized debt issuance costs (8,289 ) (9,323 ) Less: unamortized senior term note discount (2,903 ) (3,152 ) Term notes payable $ 1,388,808 $ 1,387,525

Mortgages Payable and Debt Ma27

Mortgages Payable and Debt Maturities (Tables)	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Summary of Mortgage Payable	Mortgages payable at September 30, 2017 and December 31, 2016 consist of the following: (dollars in thousands) Sep. 30, 2017 Dec. 31, 2016 4.98% mortgage note due January 1, 2021, secured by one self-storage facility with an aggregate net book value of $9.7 million, principal and interest paid monthly (effective interest rate 5.23%) $ 2,929 $ 2,966 4.065% mortgage note due April 1, 2023, secured by one self- storage facility with an aggregate net book value of $7.6 million, principal and interest paid monthly (effective interest rate 4.31%) 4,140 4,207 5.26% mortgage note due November 1, 2023, secured by one self-storage facility with an aggregate net book value of $8.0 million, principal and interest paid monthly (effective interest rate 5.57%) 3,955 4,002 5.99% mortgage note due May 1, 2026, secured by one self- storage facility with an aggregate net book value of $6.6 million, principal and interest paid monthly (effective interest rate 6.27%) 1,740 1,852 Total mortgages payable $ 12,764 $ 13,027
Summary of Debt Obligation and Interest Rate Derivatives	Accordingly, the estimates presented below are not necessarily indicative of the amounts the Company would realize in a current market exchange. Expected Maturity Date Including Discount (dollars in thousands) 2017 2018 2019 2020 2021 Thereafter Total Fair Value Line of credit - variable rate LIBOR + 1.10% (2.34% at September 30, 2017) — — $ 329,000 — — — $ 329,000 $ 329,000 Notes Payable: Term note - variable rate LIBOR+1.15% (2.38% at September 30, 2017) — — — $ 325,000 — — $ 325,000 $ 325,000 Term note - fixed rate 5.54% — — — — $ 100,000 — $ 100,000 $ 109,428 Term note - fixed rate 4.533% — — — — — $ 175,000 $ 175,000 $ 182,710 Term note - fixed rate 3.50% — — — — — $ 600,000 $ 600,000 $ 583,759 Term note - fixed rate 3.67% — — — — — $ 200,000 $ 200,000 $ 191,932 Mortgage note - fixed rate 4.98% $ 13 $ 53 $ 56 $ 59 $ 2,748 — $ 2,929 $ 3,061 Mortgage note - fixed rate 4.065% $ 22 $ 92 $ 95 $ 99 $ 104 $ 3,728 $ 4,140 $ 4,190 Mortgage note - fixed rate 5.26% $ 16 $ 67 $ 71 $ 74 $ 78 $ 3,649 $ 3,955 $ 4,203 Mortgage note - fixed rate 5.99% $ 39 $ 160 $ 170 $ 181 $ 192 $ 998 $ 1,740 $ 1,867 Interest rate derivatives - liability — — — — — — — $ 10,923 Total $ 90 $ 372 $ 329,392 $ 325,413 $ 103,122 $ 983,375 $ 1,741,764

Derivative Financial Instrume28

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2017
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Summary of Interest Rate Swap Agreements	The Company has interest rate swap agreements in effect at September 30, 2017 as detailed below to effectively convert a total of $325 million of variable-rate debt to fixed-rate debt. Notional Amount Effective Date Expiration Date Fixed Rate Paid Floating Rate Received $125 Million 9/1/2011 8/1/18 2.3700 % 1 month LIBOR $100 Million 12/30/11 12/29/17 1.6125 % 1 month LIBOR $100 Million 9/4/13 9/4/18 1.3710 % 1 month LIBOR $100 Million 12/29/17 11/29/19 3.9680 % 1 month LIBOR $125 Million 8/1/18 6/1/20 4.1930 % 1 month LIBOR
Summary of Changes in AOCL	The changes in AOCL for the three and nine months ended September 30, 2017 and 2016 are summarized as follows: (dollars in thousands) Three Months Ended September 30, 2017 Three Months Ended September 30, 2016 Nine Months Ended September 30, 2017 Nine Months Ended September 30, 2016 Accumulated other comprehensive loss beginning of period $ (19,616 ) $ (30,863 ) $ (21,475 ) $ (14,415 ) Realized loss reclassified from accumulated other comprehensive loss to interest expense 758 1,398 2,835 3,755 Unrealized loss from changes in the fair value of the effective portion of the interest rate swaps 44 1,533 (174 ) (17,272 ) Income (loss) included in other comprehensive loss 802 2,931 2,661 (13,517 ) Accumulated other comprehensive loss end of period $ (18,814 ) $ (27,932 ) $ (18,814 ) $ (27,932 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Assets and Liabilities Carried at Fair Value Measured on Recurring Basis	The following table provides the liabilities carried at fair value measured on a recurring basis as of September 30, 2017 and December 31, 2016 (in thousands): Asset (Liability) Level 1 Level 2 Level 3 September 30, 2017 Interest rate swaps $ (10,923 ) — $ (10,923 ) — December 31, 2016 Interest rate swaps $ (13,015 ) — $ (13,015 ) —

Investment in Joint Ventures (T

Investment in Joint Ventures (Tables)	9 Months Ended
	Sep. 30, 2017
Equity Method Investments And Joint Ventures [Abstract]
Summary of Company's Unconsolidated Joint Ventures	A summary of the Company’s unconsolidated joint ventures is as follows: Venture Number of Properties Company common ownership interest Carrying value of investment at Sep. 30, 2017 Carrying value of investment at Dec. 31, 2016 Sovran HHF Storage Holdings LLC (“Sovran HHF”) 1 57 20 % $85.5 million $43.8 million Sovran HHF Storage Holdings II LLC (“Sovran HHF II”) 2 30 15 % $13.4 million $13.5 million 191 III Holdings LLC (“191 III”) 3 6 20 % $9.6 million $0.7 million Life Storage-SERS Storage LLC (“SERS”) 4 3 20 % $3.6 million N/A Iskalo Office Holdings, LLC (“Iskalo”) 5 N/A 49 % ($0.4 million) ($0.4 million) Urban Box Coralway Storage, LLC (“Urban Box”) 6 1 85 % $4.1 million $4.1 million SNL/Orix 1200 McDonald Ave., LLC (“McDonald”) 7 1 5 % $2.7 million $2.7 million SNL Orix Merrick, LLC (“Merrick”) 8 1 5 % $2.5 million $2.5 million Review Avenue Partners, LLC (“RAP”) 9 1 40 % $11.7 million N/A N 32nd Street Self Storage, LLC (“N32”) 10 1 46 % $1.3 million N/A 1 2 3 4 5 6 7 8 9 10 nd
Company's Share of Unconsolidated Joint Ventures' Income (Loss)	The Company’s share of the unconsolidated joint ventures’ income (loss) is as follows: (dollars in thousands) Venture Three Months Ended September 30, 2017 Three Months Ended September 30, 2016 Nine Months Ended September 30, 2017 Nine Months Ended September 30, 2016 Sovran HHF $ 588 $ 485 $ 1,750 $ 1,563 Sovran HHF II 398 352 1,100 1,059 191 III (14 ) — 12 — SERS (43 ) — (43 ) — Urban Box — — — 15 RAP (248 ) — (749 ) — Iskalo 71 45 189 158 $ 752 $ 882 $ 2,259 $ 2,795
Summary of Unconsolidated Joint Ventures' Financial Statements	A summary of the unconsolidated joint ventures’ financial statements as of and for the nine months ended September 30, 2017 is as follows: (dollars in thousands) Balance Sheet Data: Investment in storage facilities, net $ 1,074,003 Investment in office building, net 4,872 Other assets 20,534 Total Assets $ 1,099,409 Due to the Company $ 869 Mortgages payable 455,676 Other liabilities 14,001 Total Liabilities $ 470,546 Unaffiliated partners’ equity 495,003 Company equity 133,860 Total Partners’ Equity 628,863 Total Liabilities and Partners’ Equity $ 1,099,409 Income Statement Data: Total revenues $ 68,841 Property operating expenses (23,075 ) Administrative, management and call center fees (5,829 ) Depreciation and amortization of customer list (14,684 ) Amortization of financing fees (579 ) Income tax expense (201 ) Interest expense (10,033 ) Net income $ 14,440

Earnings Per Share and Earnin31

Earnings Per Share and Earnings Per Unit (Tables)	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings Per Common Share/Unit	The following table sets forth the computation of basic and diluted earnings per common share utilizing the two-class method. Earnings Per Share (in thousands except per share data) Three Months Ended Sep. 30, 2017 Three Months Ended Sep. 30, 2016 Nine Months Ended Sep. 30, 2017 Nine Months Ended Sep. 30, 2016 Numerator: Net income (loss) attributable to common shareholders $ 35,496 $ (4,738 ) $ 75,280 $ 67,058 Denominator: Denominator for basic earnings (loss) per share – weighted average shares 46,416 46,139 46,362 42,177 Effect of Dilutive Securities: Stock options and non-vested stock 104 — 110 238 Denominator for diluted earnings (loss) per share – adjusted weighted average shares and assumed conversion 46,520 46,139 46,472 42,415 Basic earnings (loss) per common share attributable to common shareholders $ 0.76 $ (0.10 ) $ 1.62 $ 1.59 Diluted earnings (loss) per common share attributable to common shareholders $ 0.76 $ (0.10 ) $ 1.62 $ 1.58 Earnings Per Unit The following table sets forth the computation of basic and diluted earnings per common unit utilizing the two-class method. (in thousands except per unit data) Three Months Ended Sep. 30, 2017 Three Months Ended Sep. 30, 2016 Nine Months Ended Sep. 30, 2017 Nine Months Ended Sep. 30, 2016 Numerator: Net income (loss) attributable to common unitholders $ 35,496 $ (4,738 ) $ 75,280 $ 67,058 Denominator: Denominator for basic earnings (loss) per unit – weighted average units 46,416 46,139 46,362 42,177 Effect of Dilutive Securities: Stock options and non-vested stock 104 — 110 238 Denominator for diluted earnings (loss) per unit – adjusted weighted average units and assumed conversion 46,520 46,139 46,472 42,415 Basic earnings (loss) per common unit attributable to common unitholders $ 0.76 $ (0.10 ) $ 1.62 $ 1.59 Diluted earnings (loss) per common unit attributable to common unitholders $ 0.76 $ (0.10 ) $ 1.62 $ 1.58

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Reconciliation of Changes in Parent Company's Total Shareholders' Equity	The following is a reconciliation of the changes in the Parent Company’s total shareholders’ equity for the period: (dollars in thousands) Nine Months Ended September 30, 2017 Beginning balance of total shareholders’ equity $ 2,088,494 Net proceeds from the issuance of common stock through Dividend Reinvestment Plan 15,633 Purchase of outstanding shares (8,234 ) Earned portion of non-vested stock 4,905 Stock option expense 11 Deferred compensation - directors — Adjustment to redemption value on noncontrolling redeemable Operating Partnership units 155 Net income attributable to common shareholders 75,280 Amortization of terminated hedge included in AOCL 688 Change in fair value of derivatives 1,973 Dividends (136,796 ) Ending balance of total shareholders’ equity $ 2,042,109

Partners' Capital (Tables)

Partners' Capital (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Reconciliation of Changes in Total Partners' Capital	The following is a reconciliation of the changes in total partners’ capital for the period: (dollars in thousands) Nine Months Ended September 30, 2017 Beginning balance of total controlling partners’ capital $ 2,088,494 Net proceeds from the issuance of partnership units through Dividend Reinvestment Plan 15,633 Purchase of outstanding units (8,234 ) Earned portion of non-vested stock 4,905 Stock option expense 11 Deferred compensation - directors — Adjustment to redemption value on limited partners’ redeemable capital interests 155 Net income attributable to common unitholders 75,280 Amortization of terminated hedge included in AOCL 688 Change in fair value of derivatives 1,973 Distributions (136,796 ) Ending balance of total controlling partners’ capital $ 2,042,109

Organization - Additional Infor

Organization - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2017PropertyStateshares	Dec. 31, 2016shares
Organization [Line Items]
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership	99.50%
Number of self-storage properties owned and managed	704
Number of states in which self-storage properties owned and managed | State	29
Number of properties managed under joint ventures	97
Number of properties managed with no ownership	41
Units of redeemable noncontrolling interest in operating partnership | shares	217,481	217,481
Noncontrolling limited partnership unit redemption value	one common share or cash
Life Storage Solutions, LLC [Member]
Organization [Line Items]
Percentage of ownership by subsidiary	60.00%
Geographic Concentration Risk [Member] | Texas [Member] | Revenue [Member]
Organization [Line Items]
Concentration risk, percentage	23.00%
Geographic Concentration Risk [Member] | Florida [Member] | Revenue [Member]
Organization [Line Items]
Concentration risk, percentage	13.00%

Organization - Summary of Recon

Organization - Summary of Reconciliation of Noncontrolling Interests (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Redeemable Noncontrolling Interest Equity Fair Value [Abstract]
Noncontrolling interest, beginning balance			$ 18,091
Net income attributable to noncontrolling interest in the Operating Partnership	$ 171	$ (21)	343	$ 317
Distributions			(641)
Adjustment to redemption value			(155)
Noncontrolling interest, ending balance	$ 17,638		$ 17,638

Stock Based Compensation - Addi

Stock Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option expense	$ 4,000	$ 4,000	$ 11,000	$ 85,000
Amortization of non-vested stock grants and performance-based awards	$ 1,659,000	$ 1,758,000	$ 4,905,000	$ 5,515,000
Stock options exercised by employees and directors			0	0
Number of shares of non-vested stock that vested	19,537	29,205	66,565	40,086
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, share based compensation, vesting period (in years)			3 years
Aggregate fair value			$ 800,000
Performance Shares [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted under performance plan			17,888
Non-Vested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of non-vested stock issued			34,240
Aggregate fair value			$ 2,900,000
Non-Vested Shares [Member] | Vesting Period One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, share based compensation, vesting period (in years)			1 year
Non-Vested Shares [Member] | Vesting Period Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, share based compensation, vesting period (in years)			5 years
Non-Vested Shares [Member] | Vesting Period Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, share based compensation, vesting period (in years)			8 years
Non-Vested Shares [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair market value of the non-vested stock on the date of grant			$ 74.30
Non-Vested Shares [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair market value of the non-vested stock on the date of grant			$ 86.78

Investment in Storage Facilit37

Investment in Storage Facilities and Intangible Assets - Summary of Activity in Storage Facilities (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Cost:
Beginning balance	$ 4,243,308
Acquisition of storage facilities	10,089
Improvements and equipment additions	67,026
Additions to consolidated subsidiary	113
Net decrease in construction in progress	(1,784)
Dispositions	(12,357)
Ending balance	4,306,395
Accumulated Depreciation:
Beginning balance	535,704
Additions during the period	77,105
Dispositions	(10,955)
Ending balance	$ 601,854

Investment in Storage Facilit38

Investment in Storage Facilities and Intangible Assets - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)$ / shares	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)Facility$ / shares	Sep. 30, 2016USD ($)	Dec. 31, 2015USD ($)
Real Estate [Abstract]
Number of storage facilities acquired | Facility			1
Cash paid for facility acquired			$ 10,100,000
Deposits paid at the time of contract					$ 500,000
Net other liabilities assumed			$ 13,000
Issuance of Operating Partnership Units		$ 7,800,000		$ 7,800,000
Net other liabilities		7,300,000		7,300,000
Fair value of two mortgages		8,300,000		8,300,000
Amortization period for in-place customer leases on a straight-line basis			12 months
Amortization expense related to in-place customer leases	$ 100,000	$ 13,500,000	$ 24,800,000	$ 16,500,000
Amortization expense expected for 2017	24,800,000		24,800,000
Amortization expense expected for 2018	0		0
Increase in depreciation expense due to signs			500,000
Increase in depreciation expense due to facility replacement	$ 2,000,000		$ 3,600,000
Accelerated depreciation reduced basic and diluted earnings per share | $ / shares	$ 0.04		$ 0.09

Investment in Storage Facilit39

Investment in Storage Facilities and Intangible Assets - Schedule of Acquired Facilities and Purchase Price of Facilities (Detail) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)PropertyFacility	Sep. 30, 2016USD ($)
Investment Holdings [Line Items]
Number of Properties | Facility		1
Cash Paid		$ 10,100
Closing Costs Expensed	$ 25,220		$ 29,297
Illinois [Member] | Date Of Acquisition, 2/23/17 [Member]
Investment Holdings [Line Items]
Number of Properties | Property		1
Date of Acquisition		Feb. 23, 2017
Purchase Price		$ 10,089
Cash Paid		10,076
Consideration paid Value of Operating Partnership Units Issued		0
Mortgage Assumed		0
Net Other Liabilities (Assets) Assumed		13
Land		771
Building, Equipment, and Improvements		9,318
In-Place Customers Leases		0
Closing Costs Expensed		$ 0

Investment in Storage Facilit40

Investment in Storage Facilities and Intangible Assets - Schedule of Fair Value of In-Place Customer Lease Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Real Estate [Abstract]
In-place customer leases	$ 75,611	$ 75,611
Accumulated amortization	(75,573)	(50,782)
Net carrying value at the end of period	$ 38	$ 24,829

Unsecured Line of Credit and 41

Unsecured Line of Credit and Term Notes - Borrowings Outstanding on Unsecured Line of Credit and Term Notes (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Unsecured Line Of Credit And Term Notes [Line Items]
Revolving line of credit borrowings	$ 329,000	$ 253,000
Total term notes payable - gross	1,400,000	1,400,000
Less: unamortized debt issuance costs	(8,289)	(9,323)
Less: unamortized senior term note discount	(2,903)	(3,152)
Term notes payable	1,388,808	1,387,525
Term Note Due June 4, 2020 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Total term notes payable - gross	325,000	325,000
Term Note Due August 5, 2021 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Total term notes payable - gross	100,000	100,000
Term Note Due April 8, 2024 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Total term notes payable - gross	175,000	175,000
Senior Term Note Due July 1, 2026 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Total term notes payable - gross	600,000	600,000
Term Note Due July 21, 2028 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Total term notes payable - gross	$ 200,000	$ 200,000

Unsecured Line of Credit and 42

Unsecured Line of Credit and Term Notes - Additional Information (Detail) - USD ($)	Jul. 21, 2016	Jun. 20, 2016	Apr. 08, 2014	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2011	Dec. 31, 2016	Jan. 31, 2016
Unsecured Line Of Credit And Term Notes [Line Items]
Unsecured term note				$ 1,400,000,000		$ 1,400,000,000			$ 1,400,000,000
Unamortized senior term note discount				2,903,000		2,903,000			$ 3,152,000
Underwriting discount and other offering expenses							$ 15,253,000
Interest coverage ratio on debt		150.00%
Amortization expense related to deferred debt issuance costs						2,496,000	8,858,000
Maximum [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Leverage ratio percentage		60.00%
Indenture covenant percentage on unencumbered assets		150.00%
Secured Debt [Member] | Maximum [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Leverage ratio percentage		40.00%
Revolving Credit Facility [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Revolving credit limit				$ 500,000,000		$ 500,000,000				$ 300,000,000
Maturity on December 10, 2019 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Basis spread over LIBOR						1.10%
Facility fee						0.15%
Interest rate, line of credit facility				2.34%		2.34%			1.79%
Amount available on unsecured revolving line of credit				$ 171,000,000		$ 171,000,000
Line of credit facility, expiration date						Dec. 10, 2019
Maturity on June 4, 2020 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Basis spread over LIBOR						1.15%
Unsecured term note				$ 325,000,000		$ 325,000,000
Maturity in April 8, 2024 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Line of credit facility, expiration date						Apr. 8, 2024
Additional secured term note			$ 175,000,000
Term note stated interest rate				4.533%		4.533%
Maturity in April 8, 2024 [Member] | Maximum [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Term note stated interest rate				6.283%		6.283%
Maturity in August 2021 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Line of credit facility, expiration date						Aug. 5, 2021
Additional secured term note								$ 100,000,000
Term note stated interest rate								5.54%
Maturity in August 2021 [Member] | Maximum [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Term note stated interest rate								7.29%
Senior Term Note Due July 1, 2026 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Unsecured term note				$ 600,000,000		$ 600,000,000			$ 600,000,000
Senior Term Note Due July 1, 2026 [Member] | Unsecured Senior Notes [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Debt instrument principal amount		$ 600,000,000
Debt instrument percentage		3.50%
Debt instrument percentage discount to par		0.553%
Unamortized senior term note discount		$ 3,300,000
Underwriting discount and other offering expenses		5,500,000
Proceeds from senior notes, net		$ 591,200,000
Term Note Due July 21, 2028 [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Unsecured term note				200,000,000		200,000,000			$ 200,000,000
Line of credit facility, expiration date	Jul. 21, 2028
Additional secured term note	$ 200,000,000
Term note stated interest rate	3.67%
Senior Notes and Term Notes [Member]
Unsecured Line Of Credit And Term Notes [Line Items]
Amortization expense related to deferred debt issuance costs				$ 500,000	$ 500,000	$ 1,600,000	$ 1,200,000

Mortgages Payable and Debt Ma43

Mortgages Payable and Debt Maturities - Summary of Mortgage Payable (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Mortgages payable	$ 12,764	$ 13,027
4.98% Mortgage Note Due January 1, 2021 [Member]
Debt Instrument [Line Items]
Mortgages payable	2,929	2,966
4.065% Mortgage Note Due April 1, 2023 [Member]
Debt Instrument [Line Items]
Mortgages payable	4,140	4,207
5.26% Mortgage Note Due November 1, 2023 [Member]
Debt Instrument [Line Items]
Mortgages payable	3,955	4,002
5.99% Mortgage Notes Due May 1, 2026 [Member]
Debt Instrument [Line Items]
Mortgages payable	$ 1,740	$ 1,852

Mortgages Payable and Debt Ma44

Mortgages Payable and Debt Maturities - Summary of Mortgage Payable (Parenthetical) (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2017USD ($)Facility
4.98% Mortgage Note Due January 1, 2021 [Member]
Debt Instrument [Line Items]
Interest rate	4.98%
Mortgage note due date	Jan. 1, 2021
Self-storage facilities | Facility	1
Aggregate net book value of property pledged for mortgage note | $	$ 9.7
Effective interest rate	5.23%
4.065% Mortgage Note Due April 1, 2023 [Member]
Debt Instrument [Line Items]
Interest rate	4.065%
Mortgage note due date	Apr. 1, 2023
Self-storage facilities | Facility	1
Aggregate net book value of property pledged for mortgage note | $	$ 7.6
Effective interest rate	4.31%
5.26% Mortgage Note Due November 1, 2023 [Member]
Debt Instrument [Line Items]
Interest rate	5.26%
Mortgage note due date	Nov. 1, 2023
Self-storage facilities | Facility	1
Aggregate net book value of property pledged for mortgage note | $	$ 8
Effective interest rate	5.57%
5.99% Mortgage Notes Due May 1, 2026 [Member]
Debt Instrument [Line Items]
Interest rate	5.99%
Mortgage note due date	May 1, 2026
Self-storage facilities | Facility	1
Aggregate net book value of property pledged for mortgage note | $	$ 6.6
Effective interest rate	6.27%

Mortgages Payable and Debt Ma45

Mortgages Payable and Debt Maturities - Summary of Debt Obligation and Interest Rate Derivatives (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Payables due 2017	$ 90
Payables due 2018	372
Payable due 2019	329,392
Payable due 2020	325,413
Payable due 2021	103,122
Payables due Thereafter	983,375
Line of credit	329,000	$ 253,000
Term notes, net of debt issuance costs	1,400,000	1,400,000
Mortgage note, total	12,764	13,027
Total	1,741,764
Interest rate derivatives - liability	10,923	$ 13,015
Line of credit - variable rate LIBOR + 1.10% (2.34% at September 30, 2017) [Member]
Debt Instrument [Line Items]
Payable due 2019	329,000
Line of credit	329,000
Debt instrument, fair value	329,000
Term note - variable rate LIBOR+1.15% (2.38% at September 30, 2017) [Member]
Debt Instrument [Line Items]
Payable due 2020	325,000
Term notes, net of debt issuance costs	325,000
Term note, fair value	325,000
Term Note - Fixed Rate 5.54% [Member]
Debt Instrument [Line Items]
Payable due 2021	100,000
Term notes, net of debt issuance costs	100,000
Term note, fair value	109,428
Term Note - Fixed Rate 4.533% [Member]
Debt Instrument [Line Items]
Payables due Thereafter	175,000
Term notes, net of debt issuance costs	175,000
Term note, fair value	182,710
Term Note - Fixed Rate 3.50% [Member]
Debt Instrument [Line Items]
Payables due Thereafter	600,000
Term notes, net of debt issuance costs	600,000
Term note, fair value	583,759
Term Note - Fixed Rate 3.67% [Member]
Debt Instrument [Line Items]
Payables due Thereafter	200,000
Term notes, net of debt issuance costs	200,000
Term note, fair value	191,932
Mortgage Note - Fixed Rate 4.98% [Member]
Debt Instrument [Line Items]
Payables due 2017	13
Payables due 2018	53
Payable due 2019	56
Payable due 2020	59
Payable due 2021	2,748
Mortgage note, total	2,929
Debt instrument, fair value	3,061
Mortgage Note - Fixed Rate 4.065% [Member]
Debt Instrument [Line Items]
Payables due 2017	22
Payables due 2018	92
Payable due 2019	95
Payable due 2020	99
Payable due 2021	104
Payables due Thereafter	3,728
Mortgage note, total	4,140
Debt instrument, fair value	4,190
Mortgage Note - Fixed Rate 5.26% [Member]
Debt Instrument [Line Items]
Payables due 2017	16
Payables due 2018	67
Payable due 2019	71
Payable due 2020	74
Payable due 2021	78
Payables due Thereafter	3,649
Mortgage note, total	3,955
Debt instrument, fair value	4,203
Mortgage Note - Fixed Rate 5.99% [Member]
Debt Instrument [Line Items]
Payables due 2017	39
Payables due 2018	160
Payable due 2019	170
Payable due 2020	181
Payable due 2021	192
Payables due Thereafter	998
Mortgage note, total	1,740
Debt instrument, fair value	$ 1,867

Mortgages Payable and Debt Ma46

Mortgages Payable and Debt Maturities - Summary of Debt Obligation and Interest Rate Derivatives (Parenthetical) (Detail)	9 Months Ended
	Sep. 30, 2017
Line of credit - variable rate LIBOR + 1.10% (2.34% at September 30, 2017) [Member]
Debt Instrument [Line Items]
Interest rate at end of period	2.34%
Basis spread over LIBOR	1.10%
Term note - variable rate LIBOR+1.15% (2.38% at September 30, 2017) [Member]
Debt Instrument [Line Items]
Basis spread over LIBOR	1.15%
Interest rate	2.38%
Term Note - Fixed Rate 5.54% [Member]
Debt Instrument [Line Items]
Interest rate	5.54%
Term Note - Fixed Rate 4.533% [Member]
Debt Instrument [Line Items]
Interest rate	4.533%
Term Note - Fixed Rate 3.50% [Member]
Debt Instrument [Line Items]
Interest rate	3.50%
Term Note - Fixed Rate 3.67% [Member]
Debt Instrument [Line Items]
Interest rate	3.67%
Mortgage Note - Fixed Rate 4.98% [Member]
Debt Instrument [Line Items]
Interest rate	4.98%
Mortgage Note - Fixed Rate 4.065% [Member]
Debt Instrument [Line Items]
Interest rate	4.065%
Mortgage Note - Fixed Rate 5.26% [Member]
Debt Instrument [Line Items]
Interest rate	5.26%
Mortgage Note - Fixed Rate 5.99% [Member]
Debt Instrument [Line Items]
Interest rate	5.99%

Derivative Financial Instrume47

Derivative Financial Instruments - Additional Information (Detail) - USD ($)	Jun. 20, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2018	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Cash flow hedge ineffectiveness				Ineffectiveness was de minimis for the three and nine months ended September 30, 2017.
Unsecured term note		$ 1,400,000,000		$ 1,400,000,000			$ 1,400,000,000
Derivative notional amount								$ 100,000,000	$ 50,000,000
Realized loss reclassified from accumulated other comprehensive loss to interest expense		(758,000)	$ (1,398,000)	(2,835,000)	$ (3,755,000)
Fair value of interest rate swap agreements, liability		10,923,000		10,923,000			13,015,000
Net termination cost		10,900,000		10,900,000
Senior Term Note Due July 1, 2026 [Member]
Derivative [Line Items]
Unsecured term note		600,000,000		$ 600,000,000			$ 600,000,000
Settlement of forward starting swap agreements loss	$ 9,200,000
Amortized period on interest expense				10 years
Interest Expense [Member]
Derivative [Line Items]
Realized loss reclassified from accumulated other comprehensive loss to interest expense		500,000	$ 1,200,000	$ 2,100,000	$ 3,500,000
Unsecured Senior Notes [Member] | Senior Term Note Due July 1, 2026 [Member]
Derivative [Line Items]
Debt instrument principal amount	$ 600,000,000
Scenario, Forecast [Member] | Interest Expense [Member]
Derivative [Line Items]
Realized loss reclassified from accumulated other comprehensive loss to interest expense						$ 1,600,000
Interest Rate Swap [Member]
Derivative [Line Items]
Unsecured term note		325,000,000		325,000,000
Derivative notional amount		$ 125,000,000		$ 125,000,000

Derivative Financial Instrume48

Derivative Financial Instruments - Summary of Interest Rate Swap Agreements (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2017	Mar. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Notional Amount		$ 100,000,000	$ 50,000,000
Interest Rate Swap [Member]
Derivative [Line Items]
Notional Amount	$ 125,000,000
Effective Date	Sep. 1, 2011
Expiration Date	Aug. 1, 2018
Fixed Rate Paid	2.37%
Interest Rate Swap [Member] | London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Floating Rate Received	1 month LIBOR
Interest Rate Swap One [Member]
Derivative [Line Items]
Notional Amount	$ 100,000,000
Effective Date	Dec. 30, 2011
Expiration Date	Dec. 29, 2017
Fixed Rate Paid	1.6125%
Interest Rate Swap One [Member] | London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Floating Rate Received	1 month LIBOR
Interest Rate Swap Two [Member]
Derivative [Line Items]
Notional Amount	$ 100,000,000
Effective Date	Sep. 4, 2013
Expiration Date	Sep. 4, 2018
Fixed Rate Paid	1.371%
Interest Rate Swap Two [Member] | London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Floating Rate Received	1 month LIBOR
Interest Rate Swap Three [Member]
Derivative [Line Items]
Notional Amount	$ 100,000,000
Effective Date	Dec. 29, 2017
Expiration Date	Nov. 29, 2019
Fixed Rate Paid	3.968%
Interest Rate Swap Three [Member] | London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Floating Rate Received	1 month LIBOR
Interest Rate Swap Four [Member]
Derivative [Line Items]
Notional Amount	$ 125,000,000
Effective Date	Aug. 1, 2018
Expiration Date	Jun. 1, 2020
Fixed Rate Paid	4.193%
Interest Rate Swap Four [Member] | London Interbank Offered Rate (LIBOR) [Member]
Derivative [Line Items]
Floating Rate Received	1 month LIBOR

Derivative Financial Instrume49

Derivative Financial Instruments - Summary of Changes in AOCL (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Accumulated other comprehensive loss beginning of period	$ (19,616)	$ (30,863)	$ (21,475)	$ (14,415)
Realized loss reclassified from accumulated other comprehensive loss to interest expense	758	1,398	2,835	3,755
Unrealized loss from changes in the fair value of the effective portion of the interest rate swaps	44	1,533	(174)	(17,272)
Income (loss) included in other comprehensive loss	802	2,931	2,661	(13,517)
Accumulated other comprehensive loss end of period	$ (18,814)	$ (27,932)	$ (18,814)	$ (27,932)

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Carried at Fair Value Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swaps, Liability	$ (10,923)	$ (13,015)
Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swaps, Liability	(10,923)	(13,015)
Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swaps, Liability	$ (10,923)	$ (13,015)

Investment in Joint Ventures -

Investment in Joint Ventures - Summary of Company's Unconsolidated Joint Ventures (Detail) $ in Thousands	Sep. 30, 2017USD ($)Property	Dec. 31, 2016USD ($)
Schedule of Equity Method Investments [Line Items]
Carrying value of investment	$ 134,232	$ 67,300
Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	57
Company common ownership interest	20.00%
Carrying value of investment	$ 85,500	43,800
Sovran HHF Storage Holdings II LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	30
Company common ownership interest	15.00%
Carrying value of investment	$ 13,400	13,500
191 III Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	6
Company common ownership interest	20.00%
Carrying value of investment	$ 9,600	700
Life Storage-SERS Storage LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	3
Company common ownership interest	20.00%
Carrying value of investment	$ 3,600
Iskalo Office Holdings, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Company common ownership interest	49.00%
Carrying value of investment	$ (400)	(400)
Urban Box Coralway Storage, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	1
Company common ownership interest	85.00%
Carrying value of investment	$ 4,100	4,100
SNL/Orix 1200 McDonald Ave., LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	1
Company common ownership interest	5.00%
Carrying value of investment	$ 2,700	2,700
SNL Orix Merrick, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	1
Company common ownership interest	5.00%
Carrying value of investment	$ 2,500	$ 2,500
Review Avenue Partners LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	1
Company common ownership interest	40.00%
Carrying value of investment	$ 11,700
N 32nd Street Self Storage, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of Properties | Property	1
Company common ownership interest	46.00%
Carrying value of investment	$ 1,300

Investment in Joint Ventures 52

Investment in Joint Ventures - Summary of Company's Unconsolidated Joint Ventures (Parenthetical) (Detail) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2017USD ($)FacilityStore	Sep. 30, 2016USD ($)	Dec. 31, 2016USD ($)
Schedule of Equity Method Investments [Line Items]
Number of storage facilities acquired | Facility	1
Mortgages payable	$ 12,764		$ 13,027
Distributions from unconsolidated joint ventures	$ 5,071	$ 3,875
Number of self-storage facilities under contract to be acquired | Facility	1
Payment for self-storage facilities under contract	$ 12,400
Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from unconsolidated joint ventures	3,200
Excess of investment over net asset due to capitalization of acquisition related costs	1,700
Sovran HHF Storage Holdings II LLC [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from unconsolidated joint ventures	1,300
191 III Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from unconsolidated joint ventures	400
Iskalo Office Holdings, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from unconsolidated joint ventures	100
Rent paid during the period	900	$ 900
SNL/Orix 1200 McDonald Ave., LLC [Member] | Common Stock Shares [Member]
Schedule of Equity Method Investments [Line Items]
Contribution of company to joint venture as share in capital			400
SNL/Orix 1200 McDonald Ave., LLC [Member] | Preferred Stock [Member]
Schedule of Equity Method Investments [Line Items]
Contribution of company to joint venture as share in capital			2,300
SNL Orix Merrick, LLC [Member] | Common Stock Shares [Member]
Schedule of Equity Method Investments [Line Items]
Contribution of company to joint venture as share in capital			400
SNL Orix Merrick, LLC [Member] | Preferred Stock [Member]
Schedule of Equity Method Investments [Line Items]
Contribution of company to joint venture as share in capital			2,100
Review Avenue Partners LLC [Member] | Common Stock Shares [Member]
Schedule of Equity Method Investments [Line Items]
Contribution of company to joint venture as share in capital	12,500
N 32nd Street Self Storage, LLC [Member] | Common Stock Shares [Member]
Schedule of Equity Method Investments [Line Items]
Contribution of company to joint venture as share in capital	$ 1,300
Arizona [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	11
Colorado [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	4
Florida [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	3
Georgia [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	1
Georgia [Member] | Life Storage-SERS Storage LLC [Member] | Additional Storage Facilities [Member]
Schedule of Equity Method Investments [Line Items]
Mortgages payable	$ 22,000
Contribution of company to joint venture as share in capital	$ 3,600
Number of self-storage facilities under contract to be acquired | Facility	3
Payment for self-storage facilities under contract	$ 39,100
Kentucky [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	2
Nevada [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	5
New Jersey [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	2
New Jersey [Member] | Sovran HHF Storage Holdings II LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	17
Ohio [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	6
Pennsylvania [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	1
Pennsylvania [Member] | Sovran HHF Storage Holdings II LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	3
Tennessee [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	2
Texas [Member] | Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	20
Texas [Member] | Sovran HHF Storage Holdings II LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	10
Arizona, Nevada and Tennessee [Member] | Sovran HHF Storage Holdings LLC [Member] | Storage Facilities [Member]
Schedule of Equity Method Investments [Line Items]
Number of storage facilities acquired | Facility	18
Payment for property acquisition	$ 330,000
Mortgages payable	$ 135,000
Number of properties collateral for debt | Store	16
Contribution of company to joint venture as share in capital	$ 40,000
Repayment of mortgages	$ 3,200
California [Member] | 191 III Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of self-storage facilities | Facility	6
California [Member] | 191 III Holdings LLC [Member] | Six Storage Facilities [Member]
Schedule of Equity Method Investments [Line Items]
Number of storage facilities acquired | Facility	6
Payment for property acquisition	$ 104,100
Mortgages payable	57,200
Contribution of company to joint venture as share in capital	$ 9,300		$ 700

Investment in Joint Ventures 53

Investment in Joint Ventures - Additional Information (Detail) - Sovran HHF, Sovran HHF II, 191 III, SERS and RAP [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Equity Method Investments [Line Items]
Management and call center fee earned	$ 1.9	$ 1.3	$ 4.8	$ 3.8
Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Management and call center fee as a percentage of revenues	6.00%
Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Management and call center fee as a percentage of revenues	7.00%

Investment in Joint Ventures 54

Investment in Joint Ventures - Company's Share of Unconsolidated Joint Ventures' Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	$ 752	$ 882	$ 2,259	$ 2,795
Sovran HHF Storage Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	588	485	1,750	1,563
Sovran HHF Storage Holdings II LLC [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	398	352	1,100	1,059
191 III Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	(14)		12
Life Storage-SERS Storage LLC [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	(43)		(43)
Urban Box Coralway Storage, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments				15
Review Avenue Partners LLC [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	(248)		(749)
Iskalo Office Holdings, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	$ 71	$ 45	$ 189	$ 158

Investment in Joint Ventures 55

Investment in Joint Ventures - Summary of Unconsolidated Joint Ventures' Financial Statements (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Investment in storage facilities, net	$ 3,704,541		$ 3,704,541		$ 3,707,604
Other assets	5,890		5,890		29,554
Total Assets	3,884,335		3,884,335		3,857,984
Mortgages payable	12,764		12,764		13,027
Other liabilities		$ 7,300		$ 7,300
Total Liabilities	1,824,588		1,824,588		1,751,399
Unaffiliated partners’ equity	0		0		0
Company equity	2,042,109		2,042,109		2,088,494
Total Equity	2,042,109		2,042,109		$ 2,088,494
Depreciation and amortization of customer list	(26,149)	(41,405)	(101,896)	(76,082)
Amortization of financing fees			(2,496)	(8,858)
Income tax expense	(900)	(200)	1,300	(900)
Interest expense	(16,290)	$ (14,647)	(47,216)	$ (32,024)
Unconsolidated Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Investment in storage facilities, net	1,074,003		1,074,003
Investment in office building, net	4,872		4,872
Other assets	20,534		20,534
Total Assets	1,099,409		1,099,409
Due to the Company	869		869
Mortgages payable	455,676		455,676
Other liabilities	14,001		14,001
Total Liabilities	470,546		470,546
Unaffiliated partners’ equity	495,003		495,003
Company equity	133,860		133,860
Total Equity	628,863		628,863
Total Liabilities and Partners’ Equity	$ 1,099,409		1,099,409
Total revenues			68,841
Property operating expenses			(23,075)
Administrative, management and call center fees			(5,829)
Depreciation and amortization of customer list			(14,684)
Amortization of financing fees			(579)
Income tax expense			(201)
Interest expense			(10,033)
Net income			$ 14,440

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule Of Income Taxes [Line Items]
Federal and state income tax expense (benefit)	$ 900,000	$ 200,000	$ (1,300,000)	$ 900,000
Unrecognized tax benefits	0	$ 0	0	0
Deferred tax liability	2,900,000		2,900,000
Interest or penalties related to uncertain tax positions			0	$ 0
Deferred tax assets	$ 4,600,000		$ 4,600,000
Tax Year 2013 [Member]
Schedule Of Income Taxes [Line Items]
Tax years open to examination			2,013
Latest Tax Year [Member]
Schedule Of Income Taxes [Line Items]
Tax years open to examination			2,016

Earnings Per Share and Earnin57

Earnings Per Share and Earnings Per Unit - Computation of Basic and Diluted Earnings Per Common Share/Unit (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Numerator:
Net income (loss) attributable to common shareholders/unitholders	$ 35,496	$ (4,738)	$ 75,280	$ 67,058
Denominator:
Denominator for basic earnings (loss) per share/unit - weighted average shares/units	46,415,782	46,139,079	46,361,747	42,176,762
Effect of Dilutive Securities:
Stock options and non-vested stock	104,000		110,000	238,000
Denominator for diluted earnings (loss) per share/unit - adjusted weighted average shares/units and assumed conversion	46,520,311	46,139,079	46,472,294	42,414,623
Basic Earnings (loss) per common share/unit attributable to common shareholders/unitholders	$ 0.76	$ (0.10)	$ 1.62	$ 1.59
Diluted Earnings (loss) per common share/unit attributable to common shareholders/unitholders	$ 0.76	$ (0.10)	$ 1.62	$ 1.58
Life Storage LP [Member]
Numerator:
Net income (loss) attributable to common shareholders/unitholders	$ 35,496	$ (4,738)	$ 75,280	$ 67,058
Denominator:
Denominator for basic earnings (loss) per share/unit - weighted average shares/units	46,415,782	46,139,079	46,361,747	42,176,762
Effect of Dilutive Securities:
Stock options and non-vested stock	104,000		110,000	238,000
Denominator for diluted earnings (loss) per share/unit - adjusted weighted average shares/units and assumed conversion	46,520,311	46,139,079	46,472,294	42,414,623
Basic Earnings (loss) per common share/unit attributable to common shareholders/unitholders	$ 0.76	$ (0.10)	$ 1.62	$ 1.59
Diluted Earnings (loss) per common share/unit attributable to common shareholders/unitholders	$ 0.76	$ (0.10)	$ 1.62	$ 1.58

Earnings Per Share and Earnin58

Earnings Per Share and Earnings Per Unit - Additional Information (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities not included in the effect of dilutive securities	133,179	270,298	139,107	110,757
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities not included in the effect of dilutive securities	17,500		14,667

Shareholders' Equity - Reconcil

Shareholders' Equity - Reconciliation of Changes in Parent Company's Total Shareholders' Equity (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Equity [Abstract]
Beginning balance			$ 2,088,494
Net proceeds from the issuance of common stock through Dividend Reinvestment Plan			15,633
Purchase of outstanding shares			(8,234)
Earned portion of non-vested stock			4,905
Stock option expense			11
Deferred compensation - directors			0
Adjustment to redemption value on noncontrolling redeemable Operating Partnership units			155
Net income attributable to common shareholders	$ 35,496	$ (4,738)	75,280	$ 67,058
Amortization of terminated hedge included in AOCL			688
Change in fair value of derivatives			1,973
Dividends			(136,796)
Ending balance	$ 2,042,109		$ 2,042,109

Shareholders' Equity - Addition

Shareholders' Equity - Additional Information (Detail) - USD ($)	May 25, 2016	Jan. 20, 2016	Sep. 30, 2017	Sep. 30, 2016	Aug. 02, 2017	May 31, 2017
Equity [Abstract]
Common stock shares issued under equity offering program	6,900,000	2,645,000
Common stock, price per share, public offering	$ 100	$ 105.75
Proceeds from issuance of common stock	$ 665,400,000	$ 269,700,000
Common stock value authorized under equity offering program						$ 225,000,000
Buyback Program, authorized repurchase amount					$ 200,000,000
Stock repurchased during period, shares			112,554
Stock repurchased during period, value			$ 8,234,000
Stock repurchased during period, weighted average purchase price			$ 73.16
Shares issued under dividend reinvestment plan			199,809	94,050

Partners' Capital - Reconciliat

Partners' Capital - Reconciliation of Change in Total Partners' Capital (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Partners Capital [Line Items]
Net proceeds from the issuance of partnership units through Dividend Reinvestment Plan			$ 15,633
Purchase of outstanding units			(8,234)
Earned portion of non-vested stock			4,905
Stock option expense			11
Deferred compensation - directors			0
Adjustment to redemption value on limited partners’ redeemable capital interests			155
Net income (loss) attributable to common shareholders/unitholders	$ 35,496	$ (4,738)	75,280	$ 67,058
Amortization of terminated hedge included in AOCL			688
Change in fair value of derivatives			1,973
Life Storage LP [Member]
Partners Capital [Line Items]
Beginning balance of total controlling partners’ capital			2,088,494
Net proceeds from the issuance of partnership units through Dividend Reinvestment Plan			15,633
Purchase of outstanding units			(8,234)
Earned portion of non-vested stock			4,905
Stock option expense			11
Deferred compensation - directors			0
Adjustment to redemption value on limited partners’ redeemable capital interests			155
Net income (loss) attributable to common shareholders/unitholders	35,496	$ (4,738)	75,280	$ 67,058
Amortization of terminated hedge included in AOCL			688
Change in fair value of derivatives			1,973
Distributions			(136,796)
Ending balance of total controlling partners’ capital	$ 2,042,109		$ 2,042,109

Recent Accounting Pronounceme62

Recent Accounting Pronouncements - Additional Information (Details)	9 Months Ended
	Sep. 30, 2017
Revenue [Member] | Product Concentration [Member] | Revenue From Rental Products [Member] | Minimum [Member]
Product Information [Line Items]
Concentration risk, percentage	90.00%

Commitment and Contingencies -

Commitment and Contingencies - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2017USD ($)Facility
Commitment And Contingencies [Line Items]
Payment for self-storage facilities under contract	$ 12.4
Number of self-storage facilities under contract to be acquired | Facility	1
New Jersey [Member]
Commitment And Contingencies [Line Items]
Settlement agreement, amount	$ 8
Settlement agreement, amount after tax	$ 5

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Oct. 26, 2017	Sep. 30, 2017	Oct. 03, 2017
Subsequent Event [Line Items]
Dividend declared, date		Oct. 3, 2017
Dividend paid, date		Oct. 26, 2017
Dividend record, date		Oct. 13, 2017
Subsequent Event
Subsequent Event [Line Items]
Dividend per common share			$ 1
Dividend paid	$ 46.5