Percentage of established target performance criteria.

No definition available.

Name:	ck0001585389_PercentageOfEstablishedTargetPerformanceCriteria
Namespace Prefix:	ck0001585389_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of investment fee due upon closing.

+ References

No definition available.

+ Details

Name:	ck0001585389_PercentageOfInvestmentFeeDueUponClosing
Namespace Prefix:	ck0001585389_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Purchase commitment amount.

+ References

No definition available.

+ Details

Name:	ck0001585389_PurchaseCommitmentAmount
Namespace Prefix:	ck0001585389_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Purchase units of limited partnership interest.

+ References

No definition available.

+ Details

Name:	ck0001585389_PurchaseUnitsOfLimitedPartnershipInterest
Namespace Prefix:	ck0001585389_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Rate of distributions payable monthly in arrears.

+ References

No definition available.

+ Details

Name:	ck0001585389_RateOfDistributionsPayableMonthlyInArrears
Namespace Prefix:	ck0001585389_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(d))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (h)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21484-112644

+ Details

Name:	us-gaap_PreferredStockLiquidationPreference
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Description of the various rights, preferences, and privileges of the preferred partners' ownership units including: redemption, conversion, liquidation, tax status of distribution per unit and the sharing in distributions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

+ Details

Name:	us-gaap_PreferredUnitsDescription
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(01)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_PlanNameAxis=ck0001585389_PerformanceBasedAwardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=ck0001585389_LongTermIncentivePlanUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=ck0001585389_TimeBasedAwardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=ck0001585389_UpToSecondAnniversaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=ck0001585389_SSTVIOPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=ck0001585389_UpToThirdAnniversaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=ck0001585389_UpToFourthAnniversaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=ck0001585389_InvestmentThereafterMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_TitleOfIndividualAxis=srt_ExecutiveOfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	12 Months Ended
	Jan. 30, 2023	Feb. 28, 2023	Dec. 31, 2022	Dec. 31, 2021
Performance Based Awards \| LTIPs
Subsequent Event [Line Items]
Issuance of equity awards			113,429	148,387
Percentage of established target performance criteria			200.00%
Performance Based Awards \| LTIPs \| Maximum
Subsequent Event [Line Items]
Percentage of established target performance criteria			200.00%
Time Based Awards \| LTIPs
Subsequent Event [Line Items]
Issuance of equity awards			181,664	222,581
Up to second anniversary \| S S T V I O P [Member]
Subsequent Event [Line Items]
Rate of distributions payable monthly in arrears	7.00%
Up to third anniversary \| S S T V I O P [Member]
Subsequent Event [Line Items]
Rate of distributions payable monthly in arrears	8.00%
Up to fourth anniversary \| S S T V I O P [Member]
Subsequent Event [Line Items]
Rate of distributions payable monthly in arrears	9.00%
Investment Thereafter \| S S T V I O P [Member]
Subsequent Event [Line Items]
Rate of distributions payable monthly in arrears	10.00%
Subsequent Event \| Executive Officers \| Performance Based Awards \| LTIPs
Subsequent Event [Line Items]
Issuance of equity awards		271,199
Percentage of established target performance criteria		200.00%
Vesting period		3 years
Subsequent Event \| Executive Officers \| Performance Based Awards \| LTIPs \| Maximum
Subsequent Event [Line Items]
Percentage of established target performance criteria		200.00%
Subsequent Event \| Executive Officers \| Performance Based Awards \| LTIPs \| Minimum
Subsequent Event [Line Items]
Percentage of established target performance criteria		0.00%
Subsequent Event \| Executive Officers \| Time Based Awards \| LTIPs
Subsequent Event [Line Items]
Issuance of equity awards		275,308
Vesting period		4 years
Subsequent Event \| S S T V I O P [Member]
Subsequent Event [Line Items]
Percentage of investment fee due upon closing	1.00%
Purchase units of limited partnership interest	600,000
Purchase commitment amount	$ 15
Description of preferred investor distributions	The Preferred Investor will receive distributions, payable monthly in arrears, at a rate of 7.0 % per annum from the date of issuance until the second anniversary of the date of issuance, 8.0% per annum commencing thereafter until the third anniversary of the date of issuance, 9.0% per annum commencing thereafter until the fourth anniversary of the date of issuance, and 10% per annum thereafter, payable storage acquisition, development, and improvement activities, and working capital or other general partnership purposes. Each Preferred Unit has a liquidation preference of $25.00, plus all accumulated and unpaid distributions.
Preferred stock, liquidation preference per unit	$ 25.00