Document And Entity Information (USD $)
In Billions, except Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Feb. 05, 2015
Jun. 30, 2014
Document And Entity Information [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2014    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2014    
Entity Registrant Name Green Plains Inc.    
Entity Central Index Key 0001309402    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Entity Common Stock, Shares Outstanding   37,608,982  
Entity Well-known Seasoned Issuer No    
Entity Public Float     $ 1.1
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Trading Symbol gpre