Income Taxes - U.S. and Foreign Components of Earnings Before Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components Of Earnings From Continuing Operations Before Income Taxes And Provision For Income Taxes [Line Items]
U.S.	$ 144,298	$ 62,506	$ 17,279
Foreign	(872)	474	(1,147)
Income (loss) before income tax expense	143,426	62,980	16,132
LAMAR MEDIA CORP [Member]
Components Of Earnings From Continuing Operations Before Income Taxes And Provision For Income Taxes [Line Items]
U.S.	144,643	62,841	17,615
Foreign	(872)	474	(1,147)
Income (loss) before income tax expense	$ 143,771	$ 63,315	$ 16,468

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

+ Details

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

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