Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Basis of Presentation and Significant Accounting Policies [Line Items]
Net cash used in operating activities	$ (401.7)	$ (263.6)
Net cash provided by (used in) financing activities	474.7	(859.6)
ASU 2017-07 [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Income reclassified from selling, general and administrative expenses ("SG&A") to other expense (income), net		2.1
Accounting Standards Update 2016-15 [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Net cash used in operating activities		25.6
Net cash provided by (used in) financing activities		25.6
Accounting Standards Update 2016-16 [Member] \| Retained Earnings And Prepaid Expenses And Other [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Retained earnings and prepaid expenses	(9.5)
Sprue Aegis [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Revenue from related parties	$ 7.5	$ 6.7
Investment owned, percentage	23.40%

Basis of presentation and significant accounting policies.

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- Definition

Pension and other postretirement benefit plans non operating costs.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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- Definition

Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

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-Name Accounting Standards Codification
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- Definition

Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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-Name Accounting Standards Codification
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-Subparagraph (SX 210.6-07.1(c))
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