Bluegrass Acquisition - Business Acquisition, Pro Forma Information (Details) - Bluegrass Materials Company - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018
Business Acquisition [Line Items]
Total revenues	$ 1,218,904	$ 2,059,816
Net earnings attributable to Martin Marietta	$ 207,886	$ 216,756
Diluted EPS	$ 3.28	$ 3.43

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ References

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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