Note 1 - Description of Business (Details Textual)	12 Months Ended
Dec. 31, 2016
Number of Countries Where Product is Sold by Subsidiary	150

Represents the number of countries in where the subsidiary sells its products.

No definition available.

Name:	gnrc_NumberOfCountriesWhereProductIsSoldBySubsidiary
Namespace Prefix:	gnrc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration