Nature of Business and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2014 Customer	Dec. 31, 2013 Customer
Schedule Of Significant Accounting Policies [Line Items]
Realized and unrealized foreign currency transaction gain recognized in earnings	$ 1,200,000	$ 194,000
Accrued rent	5,300,000us-gaap_AccruedRentCurrentAndNoncurrent	5,100,000us-gaap_AccruedRentCurrentAndNoncurrent
Accrued rent included in other long term liabilities	4,700,000us-gaap_AccruedRentNoncurrent	4,600,000us-gaap_AccruedRentNoncurrent
Accrued rent included in other current liabilities	600,000us-gaap_AccruedRentCurrent	500,000us-gaap_AccruedRentCurrent
Aggregate gross selling price of shipments	18,300,000us-gaap_DeferredRevenueAdditions
Payment received on shipment	17,100,000
Number Of customers accounted for accounts receivable	1	2
Advertising costs	600,000us-gaap_AdvertisingExpense	1,000,000us-gaap_AdvertisingExpense
Tax benefit, minimum percentage of likelihood of being realized upon ultimate settlement	50.00%
Outside the United States
Schedule Of Significant Accounting Policies [Line Items]
Long lived assets	$ 1,400,000
Net product revenue
Schedule Of Significant Accounting Policies [Line Items]
Number of customers accounted for net product sales	1	3
Net product revenue \| Germany
Schedule Of Significant Accounting Policies [Line Items]
Customers concentration risk, percentage	19.00%	7.00%
Net product revenue \| Customer One Product Sales
Schedule Of Significant Accounting Policies [Line Items]
Customers concentration risk, percentage	72.00%	24.00%
Net product revenue \| Customer Two Product Sales
Schedule Of Significant Accounting Policies [Line Items]
Customers concentration risk, percentage		15.00%
Net product revenue \| Customer Three Product Sales
Schedule Of Significant Accounting Policies [Line Items]
Customers concentration risk, percentage		13.00%
Net product revenue \| Outside the United States
Schedule Of Significant Accounting Policies [Line Items]
Customers concentration risk, percentage	28.00%	9.00%
Accounts receivable \| Customer One Product Sales
Schedule Of Significant Accounting Policies [Line Items]
Customers concentration risk, percentage	75.00%	15.00%
Accounts receivable \| Customer Two Product Sales
Schedule Of Significant Accounting Policies [Line Items]
Customers concentration risk, percentage		13.00%
Minimum
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	3 years
Maximum
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	10 years
Capitalized costs, amortization period maximum	17 years

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Number of individual customers accounting for more than ten percent of accounts receivable.

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Number of individual customers accounting for more than ten percent of net product sales.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Total carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue or other forms of income in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount before tax of foreign currency transaction realized and unrealized gain recognized in the income statement.

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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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