The accumulated amount of amortization of goodwill as of the balance sheet date.

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Gross amount, as of the balance sheet date, of the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable), in excess of the fair value of net assets acquired in one or more business combination transactions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a,h)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

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Goodwill and Other Intangible Assets - Summary of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified											12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Customer lists and contracts [Member]	Dec. 31, 2011 Customer lists and contracts [Member]	Dec. 31, 2012 Non-competition agreements [Member]	Dec. 31, 2011 Non-competition agreements [Member]	Dec. 31, 2012 Site locations [Member]	Dec. 31, 2011 Site locations [Member]	Dec. 31, 2012 Other [Member]	Dec. 31, 2011 Other [Member]	Dec. 31, 2012 Minimum [Member] Customer lists and contracts [Member]	Dec. 31, 2012 Minimum [Member] Non-competition agreements [Member]	Dec. 31, 2012 Minimum [Member] Other [Member]	Dec. 31, 2012 Maximum [Member] Customer lists and contracts [Member]	Dec. 31, 2012 Maximum [Member] Non-competition agreements [Member]	Dec. 31, 2012 Maximum [Member] Site locations [Member]	Dec. 31, 2012 Maximum [Member] Other [Member]	Dec. 31, 2012 LAMAR MEDIA CORP [Member] Minimum [Member] Customer lists and contracts [Member]	Dec. 31, 2012 LAMAR MEDIA CORP [Member] Minimum [Member] Non-competition agreements [Member]	Dec. 31, 2012 LAMAR MEDIA CORP [Member] Minimum [Member] Other [Member]	Dec. 31, 2012 LAMAR MEDIA CORP [Member] Maximum [Member] Customer lists and contracts [Member]	Dec. 31, 2012 LAMAR MEDIA CORP [Member] Maximum [Member] Non-competition agreements [Member]	Dec. 31, 2012 LAMAR MEDIA CORP [Member] Maximum [Member] Site locations [Member]	Dec. 31, 2012 LAMAR MEDIA CORP [Member] Maximum [Member] Other [Member]	Dec. 31, 2012 Subsidiary [Member]	Dec. 31, 2011 Subsidiary [Member]	Dec. 31, 2012 Subsidiary [Member] Customer lists and contracts [Member]	Dec. 31, 2011 Subsidiary [Member] Customer lists and contracts [Member]	Dec. 31, 2012 Subsidiary [Member] Non-competition agreements [Member]	Dec. 31, 2011 Subsidiary [Member] Non-competition agreements [Member]	Dec. 31, 2012 Subsidiary [Member] Site locations [Member]	Dec. 31, 2011 Subsidiary [Member] Site locations [Member]	Dec. 31, 2012 Subsidiary [Member] Other [Member]	Dec. 31, 2011 Subsidiary [Member] Other [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Life (Years)											7 years	3 years	5 years	10 years	15 years	15 years	15 years	7 years	3 years	5 years	10 years	15 years	15 years	15 years
Gross Carrying Amount	$ 2,009,191	$ 1,928,647	$ 482,883	$ 468,371	$ 63,519	$ 63,592	$ 1,449,181	$ 1,383,076	$ 13,608	$ 13,608															$ 2,008,646	$ 1,928,102	$ 482,883	$ 468,371	$ 63,519	$ 63,592	$ 1,449,181	$ 1,383,076	$ 13,063	$ 13,063
Accumulated Amortization	1,540,879	1,451,767	455,549	451,524	62,566	61,849	1,009,631	925,291	13,133	13,103															1,540,809	1,451,726	455,549	451,524	62,566	61,849	1,009,631	925,290	13,063	13,063
Goodwill gross carrying amount	1,738,686	1,680,483																							1,727,665	1,669,462
Goodwill accumulated amortization	$ 253,536	$ 253,635																							$ 252,667	$ 252,766