Annual increase percentage for lease charges.

No definition available.

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- Definition

Derecognition of Operating Lease Obligation and Right of Use Asset

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Operating sublease, annual increase percentage for base rent.

+ References

No definition available.

+ Details

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- Definition

Permanent monthly base rent.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sublease annual increase percentage for lease charges.

+ References

No definition available.

+ Details

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- Definition

Sublease period of base rent abatement.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Sublease temporary monthly base rent.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Temporary monthly base rent.

+ References

No definition available.

+ Details

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Namespace Prefix:	goss_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

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Period Type:	instant

- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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Balance Type:	na
Period Type:	instant

- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

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-Publisher FASB
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Balance Type:	credit
Period Type:	duration

- Details

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Commitments and Contingencies - Additional Information (Details) - USD ($)			1 Months Ended		3 Months Ended
	Oct. 29, 2021	Aug. 04, 2021	Jun. 30, 2020	Nov. 30, 2019	Mar. 31, 2022	Mar. 31, 2021
Lessee, Lease, Description [Line Items]
Operating lease, weighted average discount rate					7.00%
Weighted average remaining lease term (in years)					2 years
Cash paid for operating lease liabilities					$ 800,000	$ 1,100,000
Rent expense					$ 900,000	1,000,000
Gain (loss) on litigation settlement	$ (2,400,000)
Non-cancelable Lease Agreement Entered in August 2018
Lessee, Lease, Description [Line Items]
Operating sublease, annual increase percentage for base rent					3.00%
Additional Non-cancelable Lease Agreement Entered in November 2019
Lessee, Lease, Description [Line Items]
Monthly base rent for permanent space				$ 63,425
Monthly base rent for temporary space				$ 28,745
Annual increase percentage for lease charges				3.00%
Sublease Agreement Entered in June 2020
Lessee, Lease, Description [Line Items]
Sublease monthly base rent			$ 63,425
Sublease annual increase percentage for lease charges			3.00%
Sublease period of base rent abatement (in months)			6 months
Sublease income					$ 0	$ 300,000
Lease Assignment Agreement Entered in July 2020
Lessee, Lease, Description [Line Items]
Derecognition ROU lease assets obtained in exchange for operating lease liabilities		$ 1,700,000