Description	12 Months Ended
Sep. 30, 2018
Accounting Policies [Abstract]
Description	1. Description Surmodics, Inc. and subsidiaries (“Surmodics” or the “Company”) is a leading provider of medical device and in vitro diagnostic technologies to the healthcare industry. The Company derives its revenue from three primary sources: (1) royalties and license fees from licensing our proprietary surface modification and device drug-delivery technologies to customers; the majority of revenue in the “royalties and license fees” category is in the form of royalties; (2) product revenue generated from reagent chemical sales to licensees; stabilization chemical, antigen, substrate and surface coating chemical sales to the diagnostic and biomedical research markets as well as medical device (such as balloons and catheters) and related products sales to original equipment manufacturer (“OEM”) suppliers and distributors; and (3) research and commercial development fees generated on customer projects. Basis of Presentation The consolidated financial statements include all accounts and wholly-owned subsidiaries, and have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S.”) (“GAAP”). All inter-company transactions have been eliminated.

The entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-URI http://asc.fasb.org/topic&trid=2122369

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-URI http://asc.fasb.org/topic&trid=2122149

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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