v2.4.0.6
Document and Entity Information Document (USD $)
In Millions, except Share data, unless otherwise specified
12 Months Ended
Dec. 30, 2012
Feb. 15, 2013
Jul. 01, 2012
Document Information [Line Items]      
Entity Registrant Name BLUE NILE INC    
Entity Central Index Key 0001091171    
Document Type 10-K    
Document Period End Date Dec. 30, 2012    
Amendment Flag false    
Document Fiscal Year Focus 2012    
Document Fiscal Period Focus FY    
Current Fiscal Year End Date --12-30    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Filer Category Accelerated Filer    
Entity Public Float     $ 398
Entity Common Stock, Shares Outstanding   12,464,232