Discontinued operations - Summary of Assets and Liabilities from Discontinued Operations (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Discontinued Operations And Disposal Groups [Abstract]
Accounts receivable		$ 57,587
Income taxes recoverable		157
Inventory, deposits and prepaid expenses		7,658
Property and equipment		79,910
Intangible assets		3,457
Goodwill		8,872
Deferred income taxes		64,048
Deferred income taxes valuation allowance		(63,917)
Total assets from discontinued operations		157,772
Accounts payable and accrued liabilities		57,604
Real estate debt and capital leases		45,034
Total liabilities from discontinued operations		$ 102,638

The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for assets of a disposal group, including a component of the entity (discontinued operation), to be sold or that has been disposed of through sale, as of the financial statement date.

Name:	us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

For the disposal group, including a component of the entity (discontinued operation), the aggregate of amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of accounts payable and accrued liabilities attributable to disposal group.

+ References

+ Details

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

- Definition

For a disposal group, including a component of the entity (discontinued operation), represents the deferred tax assets (net of any valuation allowances), which result from applying the applicable tax rate to net deductible temporary differences and carryforwards pertaining to each jurisdiction to which the entity is obligated to pay income tax. A deductible temporary difference is a difference between the tax basis and the carrying amount of an asset or liability in the financial statements prepared in accordance with generally accepted accounting principles that will result in deductible amounts for tax purposes in future periods if there is sufficient tax-basis income to enable the deduction to be taken.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationDeferredTaxAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount of goodwill (adjusted for any amortization recognized prior to adoption of FAS 142 and impairment charges).

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationGoodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying value (net of any accumulated amortization and write-downs) of nonphysical assets (such as copyrights, customer lists, patents, trade names, core deposits, trade secrets, and contractual rights), not elsewhere itemized.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying amount of assets not otherwise specified in the taxonomy that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying value (net of accumulated depreciation and any write-downs) of 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. 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.

+ References

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The obligations arising from the sale, disposal, or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760

+ Details

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

- Definition

Disposal group including discontinued operation deferred tax assets valuation allowance.

+ References

No definition available.

+ Details

Name:	vtnc_DisposalGroupIncludingDiscontinuedOperationDeferredTaxAssetsValuationAllowance
Namespace Prefix:	vtnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), income taxes recoverable.

+ References

No definition available.

+ Details

Name:	vtnc_DisposalGroupIncludingDiscontinuedOperationIncomeTaxesRecoverable
Namespace Prefix:	vtnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

For the disposal group, including a component of the entity (discontinued operation), carrying value of real estate and capital lease debt.

+ References

No definition available.

+ Details

Name:	vtnc_DisposalGroupIncludingDiscontinuedOperationRealEstateDebtAndCapitalLeases
Namespace Prefix:	vtnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant