Stock-Based Compensation Expense in Future for Outstanding Awards (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2013	$ 3,199
2014	1,975
2015	720
2016	30
Total	$ 5,924

Future Share Based Compensation Expense Year Three

No definition available.

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