Note 1 - Organization	9 Months Ended
Jun. 30, 2020
Notes to Financial Statements
Nature of Operations [Text Block]	1. Organization Nature of Business Natural Grocers by Vitamin Cottage, Inc. (Natural Grocers or the holding company) and its consolidated subsidiaries (collectively, the Company) operate retail stores that specialize in natural and organic groceries, body care products and dietary supplements. The Company operates its retail stores under its trademark Natural Grocers by Vitamin Cottage®. As of June 30, 2020, the Company operated 159 stores in 20 states. The Company also has a bulk food repackaging facility and distribution center in Golden, Colorado. The Company had 153 stores in 19 states as of September 30, 2019.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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