Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Jul. 27, 2018
Document and Entity Information
Entity Registrant Name	SEABOARD CORP /DE/
Entity Central Index Key	0000088121
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		1,170,550
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q2