Adjusted earnings before interest tax depreciation and amortization.

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- Definition

The amount by which consolidated debt, for purposes of calculating the debt covenant ratio, may be reduced for unrestricted cash and cash equivalents, provided no amounts are outstanding under the revolving credit facility and the AR credit facility.

+ References

No definition available.

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Debt instrument maturity date year.

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Debt instrument quarterly principal repayment percentage.

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No definition available.

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- Definition

Increase in annual interest expense due to ongoing amortization of the terminated value of the Swap agreements.

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No definition available.

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- Definition

Maximum consolidated debt reduction for unrestricted cash and cash equivalents for debt covenant calculation.

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No definition available.

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- Definition

Term loan credit facility commitment.

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No definition available.

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- Definition

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-SubTopic 470

-Section 50

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- Definition

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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

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-Paragraph 3

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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- Definition

The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- 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.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

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Period remaining on line of credit facility before it terminates, 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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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.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Long-Term Debt - Additional information (Detail) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Jun. 30, 2014	Jun. 23, 2014	Jul. 01, 2014	Jul. 02, 2014
Debt Instrument [Line Items]
Required offer price to repurchase senior notes if change of control repurchase event and downgrade below investment grade credit rating occurs	101.00%
Senior notes	$ 1,585,395,000us-gaap_LongTermDebt	$ 1,030,921,000us-gaap_LongTermDebt
Term Loan Facility Commitment	250,000,000mlm_TermLoanCreditFacilityCommitment
Outstanding letters of credit	46,485,000
Maximum consolidated debt reduction for unrestricted cash and cash equivalents for debt covenant calculation	200,000,000
Additional interest expense	1,188,000	1,108,000	1,034,000
Minimum
Debt Instrument [Line Items]
Reduction of consolidated debt in the debt ratio calculation	50,000,000
Including Acquisition Bridge Debt
Debt Instrument [Line Items]
Debt covenant	3.50x
Excluding Acquisition Bridge Debt
Debt Instrument [Line Items]
Debt covenant	3.75x
New Term Loan Facility \| 2014
Debt Instrument [Line Items]
Quarterly principal payment under under the term loan facility	1.25%
New Term Loan Facility \| 2015
Debt Instrument [Line Items]
Quarterly principal payment under under the term loan facility	1.25%
New Term Loan Facility \| There After
Debt Instrument [Line Items]
Quarterly principal payment under under the term loan facility	1.875%
Trade Receivable Credit Facility
Debt Instrument [Line Items]
Credit facility commitment							150,000,000
Outstanding borrowing under credit facility	369,575,000	234,101,000
Credit facility borrowing base	313,428,000	174,977,000
Trade Receivable Credit Facility \| Credit Agreement Amendment
Debt Instrument [Line Items]
Credit facility commitment							250,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility commitment	350,000,000
Senior unsecured revolving facility, maturity period	5 years
Debt instrument maturity period	Nov. 29, 2018
Outstanding letters of credit	2,507,000	2,507,000
Short-term Line of Credit
Debt Instrument [Line Items]
Credit facility commitment	5,000,000
Outstanding borrowing under credit facility	0	0
Texas Industries Inc. \| Amended \| Maximum
Debt Instrument [Line Items]
Debt covenant	3.50x			3.75x	3.75x
Amendment consolidated EBITDA						95,000,000
Acquisition integration expenses						70,000,000
London Interbank Offered Rate(LIBOR) \| Trade Receivable Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate							0.70%
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Interest rate on notes	6.60%
Maturity date	2018
Senior notes	299,123,000	298,893,000
Increase in annual interest expense due to ongoing amortization of the terminated value of the swap agreements	1,200,000
7% Debentures, Due 2025
Debt Instrument [Line Items]
Interest rate on notes	7.00%
Maturity date	2025
Senior notes	124,500,000	124,471,000
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Interest rate on notes	6.25%
Maturity date	2037
Senior notes	228,184,000	228,148,000
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Interest rate on notes	4.25%
Maturity date	2024
Senior notes	395,309,000					400,000,000
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Maturity date	2017
Floating Rate Senior Notes due in 2017
Debt Instrument [Line Items]
Senior notes						300,000,000
Floating Rate Senior Notes due in 2017 \| Three-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						1.10%
9.25% Senior Notes due 2020 \| Texas Industries Inc.
Debt Instrument [Line Items]
Notes repurchased								$ 650,000,000
9.25% Senior Notes due 2020 \| Texas Industries Inc. \| Amended
Debt Instrument [Line Items]
Interest rate on notes						9.25%
Maturity date						2020