Note L - Contingencies (Details Textual) (USD $)	Dec. 22, 2011
Commitments and Contingencies Disclosure [Abstract]
Number of Patents In Lawsuit	$ 3naii_NumberOfPatentsInLawsuit

The number of patents being disputed in a lawsuit.

No definition available.

Name:	naii_NumberOfPatentsInLawsuit
Namespace Prefix:	naii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant