Income Taxes - Reconciliation Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Income Tax [Line Items]
Beginning balance	$ 2,067	$ 772
Additions for tax positions related to current year	932	1,122
Additions for tax positions related to prior years	238	173
Lapse of statute of limitations	(30)
Ending balance	3,207	2,067
LAMAR MEDIA CORP. AND SUBSIDIARIES [Member]
Income Tax [Line Items]
Beginning balance	2,067	772
Additions for tax positions related to current year	932	1,122
Additions for tax positions related to prior years	238	173
Lapse of statute of limitations	(30)
Ending balance	$ 3,207	$ 2,067

Income Tax.

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 10B
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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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-SubTopic 10
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