Significant Accounting Policies - Noncurrent Deferred Tax Assets Recorded in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Equity [Abstract]
Balance at beginning of period	$ 41	$ 54
Tax effect of other comprehensive earnings	(1)	(1)
Balance at end of period	$ 40	$ 53

Accumulated other comprehensive loss, noncurrent deferred tax assets, other comprehensive earnings, tax effect, pension and postretirement benefit plans.

No definition available.

Name:	mlm_AccumulatedOtherComprehensiveLossNoncurrentDeferredTaxAssetsOtherComprehensiveEarningsTaxEffectPensionAndPostretirementBenefitPlans
Namespace Prefix:	mlm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration