Related-Party Transactions - Summary of Completed Right of First Offer ("ROFO") Acquisitions (Details) $ in Millions		12 Months Ended
Jan. 18, 2018 USD ($) site shares	Dec. 31, 2018 USD ($) site
Related Party Transaction [Line Items]
Total No. of Tenant Sites \| site		104
Total Consideration \| $		$ 75.8
Landmark Dividend Growth Fund H LLC \| Acquisition from related party \| 127-site fund H acquisition
Related Party Transaction [Line Items]
Total No. of Tenant Sites \| site	127
Total Consideration \| $	$ 59.9
Total Common Units Issued \| shares	1,506,421

The number of tenant sites and related real property interests acquired.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=109124213&loc=d3e6613-128477

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109124213&loc=d3e6578-128477

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- 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

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