XML 43 R1.htm IDEA: XBRL DOCUMENT v3.20.1
Document and Entity Information - USD ($)
$ in Billions
12 Months Ended
Mar. 31, 2020
May 18, 2020
Sep. 30, 2019
Cover [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Mar. 31, 2020    
Document Fiscal Year Focus 2020    
Document Fiscal Period Focus FY    
Trading Symbol EXP    
Entity Registrant Name EAGLE MATERIALS INC.    
Entity Central Index Key 0000918646    
Current Fiscal Year End Date --03-31    
Entity Well-known Seasoned Issuer Yes    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   41,616,959  
Entity Public Float     $ 3.7
Title of 12(b) Security Common Stock (par value $.01 per share)    
Security Exchange Name NYSE    
Entity File Number 1-12984    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 75-2520779    
Entity Address, Address Line One 5960 Berkshire Lane    
Entity Address, Address Line Two Suite 900    
Entity Address, City or Town Dallas    
Entity Address, State or Province TX    
Entity Address, Postal Zip Code 75225    
City Area Code 214    
Local Phone Number 432-2000    
Document Annual Report true    
Document Transition Report false    
Documents Incorporated by Reference Portions of the Proxy Statement for the Annual Meeting of Stockholders of Eagle Materials Inc. to be held on August 5, 2020 are incorporated by reference in Part III of this Report.