Item represents advertising revenues less direct advertising expenses for the period.

No definition available.

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- Definition

Revenue from the sale of advertising time (such as television and radio) or space (newspaper or magazine pages). May also include advertising, marketing and promotional services rendered during the reporting period.

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- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Quarterly Financial Data - Summary of Quarterly Financial Data (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended			3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013
Interim Reporting [Line Items]
Net revenues	$ 1,287,060us-gaap_AdvertisingRevenue	$ 1,245,842us-gaap_AdvertisingRevenue	$ 1,179,736us-gaap_AdvertisingRevenue
Net (loss) income applicable to common stock	253,153	39,774	7,525
Net (loss) income	253,518us-gaap_NetIncomeLoss	40,139us-gaap_NetIncomeLoss	7,890us-gaap_NetIncomeLoss
Net (loss) income per common share basic	$ 2.66us-gaap_EarningsPerShareBasic	$ 0.42us-gaap_EarningsPerShareBasic	$ 0.08us-gaap_EarningsPerShareBasic
Net (loss) income per common share - diluted	$ 2.66us-gaap_EarningsPerShareDiluted	$ 0.42us-gaap_EarningsPerShareDiluted	$ 0.08us-gaap_EarningsPerShareDiluted
LAMAR MEDIA CORP [Member]
Interim Reporting [Line Items]
Net revenues	1,287,060	1,245,842	1,179,736
Net (loss) income	287,035	40,338	8,115
Adjusted [Member]
Interim Reporting [Line Items]
Net revenues				336,696	334,998	330,433	284,933	320,352	321,141	327,744	276,605
Net revenues less direct advertising expenses				221,600	222,610	216,156	173,425	210,390	211,501	217,021	170,086
Net (loss) income applicable to common stock				207,791	34,959	15,331	(4,928)	10,094	17,003	23,031	(10,354)
Net (loss) income per common share basic				$ 2.18	$ 0.37	$ 0.16	$ (0.05)	$ 0.11	$ 0.18	$ 0.24	$ (0.11)
Net (loss) income per common share - diluted				$ 2.18	$ 0.37	$ 0.16	$ (0.05)	$ 0.11	$ 0.18	$ 0.24	$ (0.11)
Adjusted [Member] \| LAMAR MEDIA CORP [Member]
Interim Reporting [Line Items]
Net revenues				336,696	334,998	330,433	284,933	320,352	321,141	327,744	276,605
Net revenues less direct advertising expenses				221,600	222,610	216,156	173,425	210,390	211,501	217,021	170,086
Net (loss) income				$ 241,230	$ 35,103	$ 15,480	$ (4,778)	$ 10,228	$ 17,144	$ 23,178	$ (10,212)