Distribution Agreements, Net - Other Identifiable Intangible Assets Net (Detail) - Distribution Agreements [Member] - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Oct. 01, 2017	Jan. 01, 2017
Finite Lived Intangible Assets [Line Items]
Distribution agreements at cost	$ 945,895	$ 939,527
Less: Accumulated amortization	(44,064)	(26,175)
Total other identifiable intangible assets, net	$ 901,831	$ 913,352	$ 729,777	$ 234,988

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 350
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-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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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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