Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

Document and Entity Information - shares
9 Months Ended
Oct. 31, 2019
Nov. 29, 2019
Document Information [Line Items]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Oct. 31, 2019  
Document Fiscal Year Focus 2020  
Document Fiscal Period Focus Q3  
Trading Symbol SEAC  
Entity Central Index Key 0001019671  
Current Fiscal Year End Date --01-31  
Entity Filer Category Accelerated Filer  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Small Business true  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   36,842,985
Title of 12(b) Security Common Stock, $0.01 Par Value  
Security Exchange Name NASDAQ  
Entity File Number 001-38828  
Entity Tax Identification Number 04-3197974  
Entity Address, Address Line One 50 Nagog Park  
Entity Address, City or Town Acton  
Entity Address, State or Province MA  
Entity Incorporation, State or Country Code DE  
Entity Address, Postal Zip Code 01720  
City Area Code (978)  
Local Phone Number 897-0100  
Document Quarterly Report true  
Document Transition Report false  
Series A Preferred Stock [Member]    
Document Information [Line Items]    
Trading Symbol SEAC  
Title of 12(b) Security Series A Participating Preferred Stock Purchase Rights  
Security Exchange Name NASDAQ