Name:	svt_DisposalGroupIncludingDiscontinuedOperationEstimatedWindDownCosts
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The amount of impairment and divestiture costs attributable to disposal group, including, but not limited to, discontinued operation.

No definition available.

Name:	svt_DisposalGroupIncludingDiscontinuedOperationImpairmentAndDivestitureCosts
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Data Type:	xbrli:monetaryItemType
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The amount of impairment charge related to the real property attributable to disposal group, including, but not limited to, discontinued operation.

No definition available.

Name:	svt_DisposalGroupIncludingDiscontinuedOperationImpairmentChargeRelatedToRealProperty
Namespace Prefix:	svt_
Data Type:	xbrli:monetaryItemType
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The amount of to disposal group, including, on additional costs.

No definition available.

Name:	svt_DisposalGroupIncludingDiscontinuedOperationOnAdditionalCosts
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Data Type:	xbrli:monetaryItemType
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The amount of to disposal group, including, other accrued liabilities.

No definition available.

Name:	svt_DisposalGroupIncludingDiscontinuedOperationOtherAccruedLiabilities
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Data Type:	xbrli:monetaryItemType
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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

No definition available.

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Amount of operating income (loss) attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of other expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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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.

No definition available.

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Balance Type:	na
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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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

The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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Name:	us-gaap_OtherAssetImpairmentCharges
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Data Type:	xbrli:monetaryItemType
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This element represents the cash inflow during the period from the sale of a component of the entity.

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