Ownership percentage held by parent and its de facto agents.

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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 gain (loss) from deconsolidation of subsidiary and derecognition of group of assets constituting transfer of business or nonprofit activity, excluding conveyance of oil and gas mineral rights and transfer of good or service in contract with customer.

+ References

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- Definition

Amount of gain (loss) from remeasurement to fair value of retained investment in former subsidiary and group of assets constituting business or nonprofit activity deconsolidated and derecognized, excluding conveyance of oil and gas mineral rights and transfer of product or service in contract with customer.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

The difference between the carrying value and the sale price of equity securities, not separately or otherwise categorized as trading or available-for-sale. This element includes investments in which the entity holds a small ownership stake (generally, less than 20% of the shares outstanding) and cannot exert significant influence.

+ References

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Investment in Silver Creek - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Jul. 14, 2017	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Effects Of Changes Net [Line Items]
Gain on deconsolidation			$ 10,848
Equity method investment		$ 7,428	10,551
Loss on equity method investment		$ (3,123)	(849)
Maximum [Member] \| Silver Creek Pharmaceuticals Inc [Member]
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Effects Of Changes Net [Line Items]
Ownership interest percentage held by parent				50.00%
Silver Creek Pharmaceuticals Inc [Member]
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Effects Of Changes Net [Line Items]
Ownership interest percentage held		40.00%
Gain on deconsolidation			10,848
Investment at fair value	$ 11,400		11,400
Equity method investment		$ 7,400	10,600
Loss on equity method investment		$ 3,100	$ 800
Silver Creek Pharmaceuticals Inc [Member] \| Minimum [Member]
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Effects Of Changes Net [Line Items]
Ownership interest percentage held by parent and its de facto agents					50.00%
Ownership interest percentage held	20.00%
Silver Creek Pharmaceuticals Inc [Member] \| Maximum [Member]
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Effects Of Changes Net [Line Items]
Ownership interest percentage held	49.00%