Amount of excess (deficiency) of insurance coverage policy.

No definition available.

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Namespace Prefix:	svt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

In reference to the maximum insurance coverage available.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of retention payable.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Represents the amount of payment from retention from the additional insurance coverage.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- 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

+ Details

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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

+ Details

Name:	us-gaap_LitigationReserve
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-4

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-9

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Balance Type:	debit
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- Details

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Data Type:	na
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Period Type:

- Details

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Namespace Prefix:
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Note 9 - Commitments and Contingencies (Details Textual) - USD ($)		1 Months Ended	3 Months Ended
	Jun. 07, 2021	Nov. 30, 2024	Mar. 31, 2025	Jan. 13, 2022
CEO Resignation [Member]
Litigation Settlement, Amount Awarded to Other Party		$ 570,000
Estimated Litigation Liability			$ 459,000
Alleged Violation of New York Human Rights Law [Member]
Loss Contingency, Maximum Insurance Coverage				$ 3,000,000
Retention Amount Payable				$ 250,000
Additional Insurance Coverage Policy Amount			3,000,000
Retention Payable at Additional Insurance Coverage			3,000,000
Gain (Loss) from Litigation Settlement			$ (0)
Alleged Violation of New York Human Rights Law [Member] \| Minimum [Member]
Loss Contingency, Damages Sought, Value	$ 5,000,000