Name:	stev_AccumulatedAmortization
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Accumulated amortization of other deferred costs capitalized at the end of the reporting period. Does not include deferred finance costs, deferred acquisition costs of insurance companies, or deferred leasing costs for real estate operations.

No definition available.

Name:	stev_LessAccumulatedAmortization
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Data Type:	xbrli:monetaryItemType
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The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

No definition available.

Name:	stev_LessAccumulatedDepreciation
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Data Type:	xbrli:monetaryItemType
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Net technology right estimated useful life 15 years

No definition available.

Name:	stev_NetTechnologyRightEstimatedUsefulLife15Years
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Data Type:	xbrli:monetaryItemType
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Gross amount, at the balance sheet date, of long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

No definition available.

Name:	stev_PropertyAndEquipmentEstimatedUsefulLife5Years
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Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

No definition available.

Name:	stev_PropertyAndEquipmentNet
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Technology right estimated useful life 15 years

No definition available.

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The aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

No definition available.

Name:	stev_WebsiteDevelopmentCostsNet
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Data Type:	xbrli:monetaryItemType
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Gross carrying amount before accumulated amortization as of the balance sheet date of capitalized costs to ready software for sale or licensing, or for long-term internal use.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275