Consolidated Statements of Comprehensive Earnings - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Consolidated net earnings	$ 1,996	$ 1,170	$ 867
Defined benefit pension and postretirement plans:
Net gain (loss) arising during period, net of tax of $11, $(5) and $29, respectively	33	(16)	88
Prior service cost arising during period, net of tax of $0, $0 and $(12), respectively	0	0	(36)
Amortization of prior service cost, net of tax of $1, $2 and $1, respectively	5	4	3
Amortization of actuarial loss, net of tax of $0, $0 and $1, respectively	1	0	3
Amount recognized in net periodic pension cost due to settlement, net of tax of $0, $0 and $1, respectively	0	0	4
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	39	(12)	62
Foreign currency translation (loss) gain	(3)	1	(2)
Other Comprehensive Income (Loss), Net of Tax	36	(11)	60
Comprehensive Earnings Attributable to Martin Marietta	$ 2,032	$ 1,159	$ 927