Acquisition and Divestitures - Acquired Intangible Assets and Related Estimated Useful Lives (Detail) - USD ($) $ in Thousands		6 Months Ended
Mar. 18, 2016	Jun. 30, 2018
Business Acquisition [Line Items]
Weighted average useful life		8 years
Restore Flow Allografts [Member]
Business Acquisition [Line Items]
Allocated fair value		$ 4,544
Weighted average useful life		10 years 3 months 18 days
Restore Flow Allografts [Member] \| Non-Compete Agreement [Member]
Business Acquisition [Line Items]
Allocated fair value		$ 180
Weighted average useful life		5 years
Restore Flow Allografts [Member] \| Trade Name [Member]
Business Acquisition [Line Items]
Allocated fair value		$ 271
Weighted average useful life		9 years
Restore Flow Allografts [Member] \| Customer Relationships [Member]
Business Acquisition [Line Items]
Allocated fair value		$ 683
Weighted average useful life		12 years 6 months
Restore Flow Allografts [Member] \| Procurement Contracts [Member]
Business Acquisition [Line Items]
Allocated fair value		$ 617
Weighted average useful life		9 years
Restore Flow Allografts [Member] \| Technology [Member]
Business Acquisition [Line Items]
Allocated fair value		$ 2,793
Weighted average useful life		10 years 6 months
ProCol Biologic Graft [Member]
Business Acquisition [Line Items]
Allocated fair value	$ 620
Weighted average useful life		8 years 7 months 6 days
ProCol Biologic Graft [Member] \| Non-Compete Agreement [Member]
Business Acquisition [Line Items]
Allocated fair value	$ 84
Weighted average useful life	5 years
ProCol Biologic Graft [Member] \| Trade Name [Member]
Business Acquisition [Line Items]
Allocated fair value	$ 109
Weighted average useful life	9 years 6 months
ProCol Biologic Graft [Member] \| Customer Relationships [Member]
Business Acquisition [Line Items]
Allocated fair value	$ 150
Weighted average useful life	9 years
ProCol Biologic Graft [Member] \| Intellectual Property [Member]
Business Acquisition [Line Items]
Allocated fair value	$ 277
Weighted average useful life	9 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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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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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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