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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisitions - Drop-down Acquisitions - Summary of Acquisitions Completed (Details) $ in Thousands		3 Months Ended	12 Months Ended
	Jan. 18, 2018 USD ($) site	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) site
Acquisitions
Number of tenant sites acquired			104
Consideration
Borrowings and Available Cash \| $			$ 68,100
Common Units Issued to Landmark and Affiliates \| $			7,700
Total \| $			$ 75,800
Wireless Communication
Acquisitions
Number of tenant sites acquired			49
Outdoor Advertising
Acquisitions
Number of tenant sites acquired			55
Landmark Dividend Growth Fund H LLC
Consideration
Common Units Issued to Landmark and Affiliates \| $		$ 27,342
Landmark Dividend Growth Fund H LLC \| Acquisition from related party \| 127-site fund H acquisition
Acquisitions
Number of tenant sites acquired	127
Consideration
Borrowings and Available Cash \| $	$ 32,600
Common Units Issued to Landmark and Affiliates \| $	27,300
Total \| $	$ 59,900
Landmark Dividend Growth Fund H LLC \| Acquisition from related party \| 2018 Drop-down Acquisitions
Acquisitions
Number of tenant sites acquired	127
Consideration
Borrowings and Available Cash \| $	$ 32,600
Common Units Issued to Landmark and Affiliates \| $	27,300
Total \| $	$ 59,900
Landmark Dividend Growth Fund H LLC \| Wireless Communication \| Acquisition from related party \| 127-site fund H acquisition
Acquisitions
Number of tenant sites acquired	30
Landmark Dividend Growth Fund H LLC \| Wireless Communication \| Acquisition from related party \| 2018 Drop-down Acquisitions
Acquisitions
Number of tenant sites acquired	30
Landmark Dividend Growth Fund H LLC \| Outdoor Advertising \| Acquisition from related party \| 127-site fund H acquisition
Acquisitions
Number of tenant sites acquired	90
Landmark Dividend Growth Fund H LLC \| Outdoor Advertising \| Acquisition from related party \| 2018 Drop-down Acquisitions
Acquisitions
Number of tenant sites acquired	90
Landmark Dividend Growth Fund H LLC \| Renewable Power Generation \| Acquisition from related party \| 127-site fund H acquisition
Acquisitions
Number of tenant sites acquired	7
Landmark Dividend Growth Fund H LLC \| Renewable Power Generation \| Acquisition from related party \| 2018 Drop-down Acquisitions
Acquisitions
Number of tenant sites acquired	7