Business Combinations - Business Acquisition, Pro Forma Information (Details) - Bluegrass Materials Company - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Total revenues	$ 4,299.7	$ 4,178.6
Net earnings attributable to Martin Marietta	$ 489.5	$ 691.7
Diluted earnings per share	$ 7.75	$ 10.94

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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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ 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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