Number of IPR&D projects impaired based on analysis of launch expectations and technical feasibility.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
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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

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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Goodwill and Other Intangible Assets, Net - Additional Information (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($) product $ / shares	Sep. 30, 2017 USD ($) product	Sep. 30, 2018 USD ($) product $ / shares	Sep. 30, 2017 USD ($) product	Dec. 31, 2017 USD ($)	Oct. 01, 2018 $ / shares
Finite-Lived Intangible Assets
Accumulated amortization	$ 257,210,000	$ 235,000,000	$ 257,210,000	$ 235,000,000	$ 219,026,000
Amortization of intangibles	$ 13,613,000	15,316,000	$ 39,985,000	$ 46,291,000
IPR&D
Finite-Lived Intangible Assets
Number of products impaired \| product	8		16	1
Impairment of intangible assets, indefinite-lived	$ 20,600,000	$ 0	$ 100,073,000	$ 3,400,000	$ 24,596,000
Product licensing rights
Finite-Lived Intangible Assets
Intangible asset useful life			8 years 9 months 18 days		9 years 9 months 18 days
Accumulated amortization	$ 241,555,000		$ 241,555,000		$ 205,549,000
Number of products impaired \| product	6	1	10	3
Impairment of intangible assets, finite-lived	$ 9,000,000	$ 7,600,000	$ 12,900,000	$ 12,300,000
Product licensing rights \| Research and Development Expense
Finite-Lived Intangible Assets
Impairment of intangible assets, finite-lived	$ 2,300,000		$ 4,100,000	$ 1,600,000
Minimum
Finite-Lived Intangible Assets
Intangible asset useful life			1 year
Maximum
Finite-Lived Intangible Assets
Intangible asset useful life			30 years
Common Stock
Finite-Lived Intangible Assets
Share price (in dollars per share) \| $ / shares	$ 12.98		$ 12.98
Subsequent Event \| Common Stock
Finite-Lived Intangible Assets
Share price (in dollars per share) \| $ / shares						$ 5.36