Debt Instrument Amount Redeemed

No definition available.

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- Definition

Debt Instrument Convertible Interest Expense Non Cash

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Redemption percentage price of bonds face amount prior to a designated date.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Percentage of aggregate principle which may be redeemed at any time at a specified price.

+ References

No definition available.

+ Details

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- Definition

Percentage premium which may be required for repayment if the Company undergoes a change in control.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Line Of Credit Facility Amended And Restated Date

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Loss On Redemption Of Senior Notes

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage Of Aggregate Principal Amount Of Notes Redeemed

+ References

No definition available.

+ Details

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Namespace Prefix:	lamr_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Ratio of indebtedness to net capital minimum.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Ratio of indebtedness to net capital one.

+ References

No definition available.

+ Details

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- Definition

Redemption Of Aggregate Principal Amount Of Outstanding Notes

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Details

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Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph e

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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- Definition

Amount of letters of credit outstanding under debtor-in-possession financing arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

+ Details

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Long-term Debt - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended	0 Months Ended
	Apr. 18, 2014	Dec. 31, 2014	Apr. 21, 2014	Apr. 22, 2010	Feb. 09, 2012	Oct. 30, 2012	Jan. 10, 2014	Feb. 03, 2014
Debt Instrument [Line Items]
Interest rate on convertible notes	7.875%
Aggregate principal amount of debt issued		$ 1,899,895,000us-gaap_DebtInstrumentFaceAmount
Amended and restated date	Apr. 18, 2014
Remaining borrowing capacity under revolving credit facility		328,154,000
Revolving credit facility maturity date		Feb. 02, 2019
LIBO Rate [Member]
Debt Instrument [Line Items]
Term A Loan Adjusted Base Rate	2.25%
Ratio of indebtedness to net capital minimum	1
Ratio of indebtedness to net capital one	3.00
Base Rate [Member]
Debt Instrument [Line Items]
Term A Loan Adjusted Base Rate	1.00%
Ratio of indebtedness to net capital minimum	1
Ratio of indebtedness to net capital one	3.00
Debt Ratio Less Than or Equal to Four Point Two Five [Member] \| LIBO Rate [Member]
Debt Instrument [Line Items]
Term A Loan Adjusted Base Rate	2.00%
Ratio of indebtedness to net capital minimum	1
Ratio of indebtedness to net capital one	4.25
Debt Ratio Less Than or Equal to Three [Member]
Debt Instrument [Line Items]
Term A Loan Adjusted Base Rate	1.75%
Debt Ratio Less Than or Equal to Three [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Term A Loan Adjusted Base Rate	0.75%
Letter of Credit [Member]
Debt Instrument [Line Items]
Outstanding revolving credit facility		65,000,000
Letter of credit outstanding		6,846,000
Term A Loan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing limit of incremental loan facility	300,000,000
7 7/8% Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes		7.875%		7.875%
Aggregate principal amount of debt issued	400,000,000			400,000,000
Net proceeds from the issuance of debt				392,000,000
Aggregate principal amount redeemed			400,000,000
Loss on transaction			20,847,000
Interest rate on convertible notes			7.875%
Number of notes outstanding		0
Non cash loss			5,095,000
5 7/8% Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes		5.875%			5.875%
Aggregate principal amount of debt issued					500,000,000
Net proceeds from the issuance of debt					489,000,000
Redemption percentage of aggregate principal amount of senior notes					35.00%
Additional redeemed percentage of aggregate principal amount					105.875%
Redemption percentage of issued notes which remain outstanding					65.00%
Redemption percentage equal to principal amount include aggregate premium					100.00%
Redemption price percentage of the principal amount to be purchased					101.00%
5% Senior Subordinated Notes [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes		5.00%				5.00%
Aggregate principal amount of debt issued						535,000,000
Net proceeds from the issuance of debt						527,100,000
Redemption percentage of aggregate principal amount of senior notes						35.00%
Additional redeemed percentage of aggregate principal amount						105.00%
Redemption percentage of issued notes which remain outstanding						65.00%
Redemption percentage equal to principal amount include aggregate premium						100.00%
Redemption price percentage of the principal amount to be purchased						101.00%
5 3/8% Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate on convertible notes		5.375%					5.375%
Aggregate principal amount of debt issued							510,000,000
Net proceeds from the issuance of debt							502,300,000
Redemption percentage of aggregate principal amount of senior notes						35.00%
Additional redeemed percentage of aggregate principal amount						105.375%
Redemption percentage of issued notes which remain outstanding						65.00%
Redemption percentage equal to principal amount include aggregate premium						100.00%
Redemption price percentage of the principal amount to be purchased						101.00%
Senior Credit Facility [Member]
Debt Instrument [Line Items]
Non cash loss							5,176,000
Senior Credit Facility [Member] \| Letter of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing limit of incremental loan facility								400,000
Incremental Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing limit of incremental loan facility	500,000,000							$ 500,000,000