Leases - Supplemental Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Sep. 30, 2019
Assets and Liabilities, Lessee [Abstract]
Operating lease non-current asset	$ 14,937	$ 0
Total lease assets	14,937
Operating Lease, Liability, Current	2,540	0
Operating lease non-current liability	16,799	$ 0
Total lease liabilities	$ 19,339

Lease Liability

No definition available.

Name:	dgii_LeaseLiability
Namespace Prefix:	dgii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease Right Of Use Asset

+ References

No definition available.

+ Details

Name:	dgii_LeaseRightOfUseAsset
Namespace Prefix:	dgii_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_AssetsAndLiabilitiesLesseeAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

+ Details

Name:	us-gaap_OperatingLeaseLiabilityCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

+ Details

Name:	us-gaap_OperatingLeaseLiabilityNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

+ Details

Name:	us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant