Accrued research and development expense.

No definition available.

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- Definition

Average trading period from date of purchase right.

+ References

No definition available.

+ Details

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- Definition

Contingently issuable equity awards fair value.

+ References

No definition available.

+ Details

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- Definition

Long-term purchase commitment, additional amount cancellable upon notice.

+ References

No definition available.

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- Definition

Market value of shares to be purchased under each right.

+ References

No definition available.

+ Details

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- Definition

Number of separate rights to purchase shares of common stock.

+ References

No definition available.

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- Definition

Prepaid manufacturing services.

+ References

No definition available.

+ Details

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- Definition

Term of manufacturing commitments.

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed after one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(10))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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- Definition

Shares issuable for little or no cash consideration upon the satisfaction of certain conditions (contingently issuable shares) are considered outstanding common shares and included in the computation of basic Earnings Per Share as of the date that all necessary conditions have been satisfied (in essence, when issuance of the shares is no longer contingent). Outstanding common shares that are contingently returnable (that is, subject to recall) are treated in the same manner as contingently issuable shares. Contingently issuable shares include shares that (a) will be issued in the future upon the satisfaction of specified conditions, (b) have been placed in escrow and all or part must be returned if specified conditions are not met, or (c) have been issued but the holder must return all or part if specified conditions are not met. The number of contingently issuable shares is determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e2646-109256

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Contract Manufacturing Agreements - Additional Information (Detail)	1 Months Ended	9 Months Ended
	Aug. 31, 2017 USD ($) Right $ / shares shares	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Long Term Purchase Commitment [Line Items]
Accounts payable		$ 15,163,000	$ 9,304,000
Accrued research and development		16,675,000	44,973,000
Prepaid and other long-term assets		20,788,000	$ 9,609,000
Lonza Manufacturing Services Agreement
Long Term Purchase Commitment [Line Items]
Contingently issuable equity awards aggregate fair value		0
Term of manufacturing commitments	10 years
Lonza Manufacturing Services Agreement \| Common Stock
Long Term Purchase Commitment [Line Items]
Number of separate rights to purchase shares of common stock \| Right	2
Follow on offering price per share \| $ / shares	$ 1.00
Average trading period from date of purchase right	20 days
Lonza Manufacturing Services Agreement \| Common Stock \| Maximum
Long Term Purchase Commitment [Line Items]
Aggregate market value of shares to be purchased under each right	$ 15,000,000
Number of shares to be purchased under each right \| shares	500,000
CMC ICOS Biologics Inc
Long Term Purchase Commitment [Line Items]
Accounts payable		400,000
Accrued research and development		300,000
Prepaid manufacturing services		4,100,000
Hovione, Limited
Long Term Purchase Commitment [Line Items]
Prepaid and other long-term assets		12,500,000
Hovione, Limited \| Maximum
Long Term Purchase Commitment [Line Items]
Cancellable additional purchase commitments		$ 2,900,000