Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Allowance for doubtful accounts	$ 7,957	$ 7,615
Accumulated amortization	14,764	25,180
Shares held in treasury	0us-gaap_TreasuryStockShares	17,216,635us-gaap_TreasuryStockShares
LAMAR MEDIA CORP [Member]
Allowance for doubtful accounts	7,957	7,615
Accumulated amortization	$ 5,476	$ 15,893
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	3,000	3,000
Common stock, shares issued	100	100
Common stock, shares outstanding	100	100
Series AA Preferred Stock [Member]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, cumulative dividends	$ 63.80	$ 63.80
Preferred stock, shares authorized	5,720	5,720
Preferred stock, shares issued	5,720	5,720
Preferred stock, shares outstanding	5,720	5,720
Preferred Class A [Member]
Preferred stock, par value	$ 638	$ 638
Preferred stock, cumulative dividends	$ 63.80	$ 63.80
Preferred stock, shares authorized	0	10,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common Class A [Member]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	362,500,000	175,000,000
Common stock, shares issued	80,933,071	97,426,144
Common stock, shares outstanding	80,933,071	80,209,509
Common Class B [Member]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	37,500,000	37,500,000
Common stock, shares issued	14,610,365	14,610,365
Common stock, shares outstanding	14,610,365	14,610,365

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