- Definition

Amount of additional cumulative credit available for transfers to parent company under the terms of Lamar Media Corp.'s senior credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	lamr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Balance of permitted transfers to parent company allowed under the terms of Lamar Media Corp.'s senior subordinated and senior notes.

+ References

No definition available.

+ Details

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Namespace Prefix:	lamr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Description of Provisions On senior credit facility transfers to Parent Company subject to additional restrictions.

+ References

No definition available.

+ Details

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Namespace Prefix:	lamr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum actual holdings debt ratio.

+ References

No definition available.

+ Details

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Namespace Prefix:	lamr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum holding debt ratio for applicability of restriction on transfer.

+ References

No definition available.

+ Details

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Namespace Prefix:	lamr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Distribution Restrictions - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)	Mar. 31, 2021 USD ($)	Feb. 06, 2020	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Balance of permitted transfers to parent company	$ 3,625,712	$ 3,667,145		$ 3,389,763
Description of provisions on senior credit facility transfers to Lamar Advertising not subject to additional restrictions	(i) the total debt ratio is less than 7.0 to 1 and (ii) the secured debt ratio does not exceed 4.5 to 1.
Debt ratio	7.0	7.0
Debt ratio related to actual position on senior credit facility	7.0	7.0
Secured debt ratio			3.25
Available cumulative credit	$ 2,376,192	$ 2,417,625
Secured Debt [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Secured debt ratio	4.5	4.5
LAMAR MEDIA CORP [Member] \| Secured Debt [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Secured debt ratio	4.5	4.5