Business combination acquired mineral reserves.

No definition available.

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- Definition

Business combination agreed consideration.

+ References

No definition available.

+ Details

Name:	mlm_BusinessCombinationAgreedConsideration
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Period Type:	instant

- Definition

Business combinations.

+ References

No definition available.

+ Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

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

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

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Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_BusinessAcquisitionAxis=mlm_BluegrassMaterialsCompanyMember
Namespace Prefix:
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- Details

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- Details

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- Details

Name:	us-gaap_StatementGeographicalAxis=stpr_TX
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- Details

Name:	us-gaap_BusinessAcquisitionAxis=mlm_RatliffReadyMixLimitedPartnershipMember
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Business Combinations - Additional Information (Detail)	1 Months Ended		12 Months Ended
Business Combinations - Additional Information (Detail)	Jul. 31, 2016 USD ($)	Feb. 29, 2016 T	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jun. 26, 2017 USD ($)
Business Combinations [Line Items]
Acquisition-related expenses incurred			$ 8,638,000	$ 909,000	$ 6,346,000
Bluegrass Materials Company
Business Combinations [Line Items]
Business acquisition agreed amount to acquire						$ 1,625,000,000
Acquisition-related expenses incurred			$ 8,638,000
Colorado \| Minimum
Business Combinations [Line Items]
Acquisition of mineral reserves \| T		500,000,000
Central Texas \| Ratliff
Business Combinations [Line Items]
Ownership interest percentage under equity method, prior to acquisition	40.00%
Gain resulting from remeasure of existing interest to fair value upon closing of transaction	$ 5,863,000