Fair Value Measurements - Additional Information (Detail) - USD ($)	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Fair Value Disclosures [Abstract]
Assets measured at fair value			$ 0
Liabilities measured at fair value			0
Fair value, assets transfers from Level 1 to Level 2 measurement	$ 0		0
Fair value, assets transfers from Level 2 to Level 1 measurement	0		0
Fair value, assets transfers from Level 1 to Level 3 measurement	0		0
Fair value, assets transfers from Level 3 to Level 1 measurement	0		$ 0
Restricted investments	$ 1,401,000	$ 1,401,000

Fair Value assets level 1 to level 2 transfers amount 1.

No definition available.

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- Definition

Fair value assets level 1 to level 3 transfers amount.

+ References

No definition available.

+ Details

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- Definition

Fair value assets level 2 to level 1 transfers amount 1.

+ References

No definition available.

+ Details

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- Definition

Fair value assets level 3 to level 1 transfers amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	mcrb_
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- References

No definition available.

+ Details

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-SubTopic 10
-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

+ Details

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

+ Details

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- Definition

This element represents the noncurrent portion of investments which are not defined as or included in marketable (debt, equity, or other) securities that are pledged or subject to withdrawal restrictions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480632/954-210-45-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480602/954-210-50-2

+ Details

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