Investment in Silver Creek - Schedule of Gain on Deconsolidation (Detail) - USD ($) $ in Thousands		12 Months Ended
Jul. 14, 2017	Dec. 31, 2017
Minority Interest [Line Items]
Carrying value of non-controlling interest		$ (1,852)
Gain recognized on deconsolidation of Silver Creek		10,848
Silver Creek Pharmaceuticals Inc [Member]
Minority Interest [Line Items]
Fair value of the Company's retained investment in Silver Creek	$ 11,400	11,400
Carrying value of non-controlling interest		(1,852)
Derecognition of Silver Creek's net liabilities		1,300
Gain recognized on deconsolidation of Silver Creek		$ 10,848

Deconsolidation of carrying value of non-controlling interest.

No definition available.

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- Definition

Derecognition of net liabilities.

+ References

No definition available.

+ Details

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- Definition

The amount of the gain (loss) recognized by the parent and included in its attributable portion of net income for the period due to deconsolidation of a subsidiary or derecognition of a group of assets. The gain (loss) recognized and included in the net income attributable to the parent for the period is generally computed as the difference between: (a) the aggregate of: (1) the fair value of any consideration received; (2) the fair value of any retained noncontrolling investment in the former subsidiary at the date the subsidiary was deconsolidated; and (3) the carrying amount of any noncontrolling interest in the former subsidiary (including any accumulated other comprehensive income attributable to the noncontrolling interest) at the date the subsidiary was deconsolidated and (b) the carrying amount of the former subsidiary's assets and liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4582445-111684

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- Definition

In connection with deconsolidation of a subsidiary or derecognition of a group of assets, the portion of any gain (loss) recognized by the parent, during the period, which is related to the remeasurement of any retained investment in the former subsidiary or group of assets to its fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4582445-111684

+ Details

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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.

+ Details

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