The cash proceeds related to the formation of a consolidated joint venture.

No definition available.

Name:	safe_CashProceedsFromFormationOfConsolidatedJointVenture
Namespace Prefix:	safe_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The acquisition price of Ground Leases.

+ References

No definition available.

+ Details

Name:	safe_GroundLeaseAcquisition
Namespace Prefix:	safe_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The purchase price to acquire joint venture partner's share of Ground Leases.

+ References

No definition available.

+ Details

Name:	safe_GroundLeaseAcquisitionOfJointVenturePartnerShare
Namespace Prefix:	safe_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of a Ground Lease acquisition purchase price that has been funded.

+ References

No definition available.

+ Details

Name:	safe_GroundLesseeAcquisitionAmountFunded
Namespace Prefix:	safe_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percent of internal rate of return.

+ References

No definition available.

+ Details

Name:	safe_InternalRateOfReturn
Namespace Prefix:	safe_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of gross valuation of joint venture.

+ References

No definition available.

+ Details

Name:	safe_JointVentureGrossValuation
Namespace Prefix:	safe_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The management fee income as percent of invested equity.

+ References

No definition available.

+ Details

Name:	safe_ManagementFeeIncomeAsPercentOfInvestedEquity
Namespace Prefix:	safe_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The term of management fee income.

+ References

No definition available.

+ Details

Name:	safe_ManagementFeeIncomeTerm
Namespace Prefix:	safe_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of Ground Lease acquired during the period

+ References

No definition available.

+ Details

Name:	safe_NumberOfGroundLeasesAcquired
Namespace Prefix:	safe_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the earliest exercise date for having an option to acquire non-controlling interest in joint venture.

+ References

No definition available.

+ Details

Name:	safe_OptionToAcquireNonControllingInterestInJointVentureEarliestExerciseDate
Namespace Prefix:	safe_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of ground leases paid to acquire investment in joint venture.

+ References

No definition available.

+ Details

Name:	safe_PaymentsToAcquireInvestmentNumberOfGroundLeasesContributed
Namespace Prefix:	safe_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The cap of promote fee income as multiple of invested capital.

+ References

No definition available.

+ Details

Name:	safe_PromoteFeeIncomeCapMultipleOfInvestedCapital
Namespace Prefix:	safe_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

The percent of promote fee income.

+ References

No definition available.

+ Details

Name:	safe_PromoteFeeIncomePercent
Namespace Prefix:	safe_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying amount of the equity interests owned by noncontrolling shareholders, partners, or other equity holders in joint ventures included in the entity's consolidated financial statements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 16
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481231/810-10-45-16

+ Details

Name:	us-gaap_MinorityInterestInJointVentures
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-13

+ Details

Name:	us-gaap_PaymentsToAcquireInterestInJointVenture
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsidiaryOrEquityMethodInvesteeCumulativePercentageOwnershipAfterAllTransactions
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Details

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

- Details

Name:	dei_LegalEntityAxis=safe_SovereignWealthFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=safe_JointVentureForNewAcquisitionsOfGroundLeasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=safe_BrookfieldJvMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=safe_BrookfieldCorporationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

Name:	srt_CounterpartyNameAxis=safe_SovereignWealthFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Net Investment in Sales-type Leases and Ground Lease Receivables - Joint Venture (Details) $ in Thousands		1 Months Ended	6 Months Ended		16 Months Ended
	Aug. 30, 2024 USD ($) lease	May 31, 2023 USD ($)	Jun. 30, 2026 USD ($) lease	Jun. 30, 2025 USD ($)	Aug. 30, 2024 USD ($) lease
Joint venture
Earliest exercise date \| lease			7
Ground Lease acquisition purchase price			$ 107,725	$ 54,948
Carrying value of noncontrolling interest acquired	$ 46,000				$ 46,000
Joint Venture for New Acquisitions of Ground Leases
Joint venture
Joint venture commitments		$ 275,000
Controlling interest in joint venture		55.00%
Percent of Promote fee			15.00%
Internal rate of return			9.00%
Promote fee cap percent			1.275
Number of Ground Leases acquired \| lease	9				9
Ground Lease acquisition purchase price					$ 170,400
Funded amount of Ground Lease acquisition	$ 101,200				$ 101,200
Sovereign wealth fund \| Joint Venture for New Acquisitions of Ground Leases
Joint venture
Joint venture commitments		$ 225,000
Joint venture for new acquisitions of Ground Leases \| Sovereign wealth fund
Joint venture
Ownership percentage		45.00%
Brookfield JV
Joint venture
Acquired interest ground leases \| lease			7
Cash at gross valuation			$ 348,000
Cash proceeds from the formation of consolidated joint venture			$ 170,500
Brookfield JV \| Brookfield Corporation
Joint venture
Ownership percentage			49.00%
First five year following acquisition \| Joint Venture for New Acquisitions of Ground Leases
Joint venture
Percent of management fee			0.25%
Management fee term			5 years
After five years of acquisition \| Joint Venture for New Acquisitions of Ground Leases
Joint venture
Percent of management fee			0.15%
Sovereign wealth fund
Joint venture
Purchase of joint venture partner share of Ground Leases	$ 48,300