Document And Entity Information
9 Months Ended
Oct. 02, 2011
Nov. 01, 2011
Document And Entity Information [Abstract]
Document Type 10-Q
Amendment Flag false
Document Period End Date Oct. 02, 2011
Document Fiscal Period Focus Q3
Document Fiscal Year Focus 2011
Entity Registrant Name NATIONAL PRESTO INDUSTRIES INC
Entity Central Index Key 0000080172
Current Fiscal Year End Date --12-31
Entity Filer Category Accelerated Filer
Entity Common Stock, Shares Outstanding 6,873,647