XML 13 R1.htm IDEA: XBRL DOCUMENT v3.6.0.2
Document And Entity Information - shares
9 Months Ended
Dec. 31, 2016
Feb. 07, 2017
Document Information [Line Items]    
Entity Registrant Name Cyanotech Corp  
Entity Central Index Key 0000768408  
Trading Symbol cyan  
Current Fiscal Year End Date --03-31  
Entity Filer Category Smaller Reporting Company  
Entity Current Reporting Status Yes  
Entity Voluntary Filers No  
Entity Well-known Seasoned Issuer No  
Entity Common Stock, Shares Outstanding (in shares)   5,668,881
Document Type 10-Q  
Document Period End Date Dec. 31, 2016  
Document Fiscal Year Focus 2017  
Document Fiscal Period Focus Q3  
Amendment Flag false