Significant Accounting Policies - Comprehensive Earnings Attributable to Martin Marietta Materials Incorporated (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 294	$ 348	$ 1,339	$ 469
Other comprehensive earnings, net of tax	1	2	1	3
Earnings attributable to Martin Marietta	$ 295	$ 350	$ 1,340	$ 472