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["Document and Entity Information","Apr. 09, 2025"]
["Cover [Abstract]"," "]
["Document Type","8-K"]
["Amendment Flag","false"]
["Document Period End Date","Apr.  09,  2025"]
["Entity File Number","001-12744"]
["Entity Registrant Name","Martin Marietta Materials, Inc."]
["Entity Central Index Key","0000916076"]
["Entity Incorporation, State or Country Code","NC"]
["Entity Tax Identification Number","56-1848578"]
["Entity Address, Address Line One","4123 Parklake Avenue"]
["Entity Address, City or Town","Raleigh"]
["Entity Address, State or Province","NC"]
["Entity Address, Postal Zip Code","27612"]
["City Area Code","919"]
["Local Phone Number","781-4550"]
["Title of 12(b) Security","Common Stock, $.01 par value per share"]
["Trading Symbol","MLM"]
["Security Exchange Name","NYSE"]
["Entity Emerging Growth Company","false"]
["Written Communications","false"]
["Soliciting Material","false"]
["Pre-commencement Tender Offer","false"]
["Pre-commencement Issuer Tender Offer","false"]