Segment Reporting - Components of Unallocated Assets (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Segment Reporting, Asset Reconciling Item [Line Items]
Property, plant and equipment, net	$ 1,908us-gaap_PropertyPlantAndEquipmentNet	$ 1,854us-gaap_PropertyPlantAndEquipmentNet
Deferred tax assets	543us-gaap_DeferredTaxAssetsNetNoncurrent	487us-gaap_DeferredTaxAssetsNetNoncurrent
Total Assets	38,211us-gaap_Assets	42,854us-gaap_Assets
Unallocated Assets [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Cash	6,973	12,863
Other current assets		450
Property, plant and equipment, net	21	25
Deferred tax assets	543	487
Total Assets	$ 7,537	$ 13,825

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

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

-Publisher FASB

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- Definition

Amount after allocation of valuation allowances of noncurrent deferred tax asset attributable to deductible temporary differences and carryforwards. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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

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Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

+ References

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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