Company and Nature of Business - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Accumulated deficit	$ 586,894	$ 567,465
Cash and cash equivalents	71,983	127,674
Short-term investments	41,721	$ 33,139
Dunkirk, NY \| Manufacturing Facility
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Cash and cash equivalents	$ 8,700

Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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