Corporate restructuring headcount reduction expected to complete fully month and year.

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- Definition

Corporate restructuring headcount reduction expected to complete substantially month and year.

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Debt instrument prepayment penalty.

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Debt instrument prepayments of debt.

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- Definition

Number of employees after headcount reduction.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

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No definition available.

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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- Definition

Amount expected to be recognized in earnings for the specified restructuring cost.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Date the event occurred after the balance sheet date but before financial statements are issues or available to be issued, in CCYY-MM-DD format.

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Subsequent Events - Additional Information (Detail) $ in Thousands				1 Months Ended	3 Months Ended
	May 07, 2019 USD ($)	Apr. 15, 2019 USD ($)	Apr. 04, 2019 USD ($) Employee	May 31, 2019 USD ($)	Mar. 31, 2019 USD ($)
Subsequent Event [Line Items]
Proceeds from sale of equity securities					$ 29,500
Proceeds on sale of property and equipment					615
Term Loan [Member] \| Hercules Capital, Inc [Member] \| Loan Agreement [Member]
Subsequent Event [Line Items]
Aggregate principal amount of loan					$ 15,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Subsequent event, date			Apr. 30, 2019
Number of employees after headcount reduction \| Employee			13
Corporate restructuring headcount reduction expected to complete fully, month and year			2019-07
Corporate restructuring headcount reduction expected to complete substantially, month and year			2019-05
Subsequent Event [Member] \| Laboratory Equipment [Member]
Subsequent Event [Line Items]
Proceeds on sale of property and equipment				$ 1,300
Subsequent Event [Member] \| Silver Creek Pharmaceuticals Inc [Member]
Subsequent Event [Line Items]
Proceeds from sale of equity securities	$ 7,800
Subsequent Event [Member] \| Term Loan [Member] \| Hercules Capital, Inc [Member] \| Loan Agreement [Member]
Subsequent Event [Line Items]
Prepayment penalty		$ 200
Payoff amount		$ 16,000
One-time Termination Benefits [Member] \| Minimum [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Expenses for one-time termination			$ 1,500
One-time Termination Benefits [Member] \| Maximum [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Expenses for one-time termination			$ 1,700