Asset Acquisition and License Agreements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Asset Acquisition [Line Items]
Restricted cash (SRX Cardio)	$ 174	$ 178
Net loss attributable to Non Controlling interest (SRX Cardio)	$ (45)
SRX Cardio
Asset Acquisition [Line Items]
Variable interest entity, Terms of arrangements	Accordingly, we have consolidated the financial statements of SRX Cardio since inception of the agreement on December 1, 2015 by (a) eliminating all intercompany balances and transactions; and (b) allocating loss attributable to the noncontrolling interest in SRX Cardio to net loss attributable to noncontrolling interest in our consolidated statement of operations and reflecting noncontrolling interest on our consolidated balance sheet.
Restricted cash (SRX Cardio)	$ 200

Asset acquisition.

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- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=65897068&loc=SL4591551-111686

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=64809438&loc=SL4573702-111684

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Description of the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, that could require the reporting entity to provide financial support (for example, liquidity arrangements and obligations to purchase assets) to the Variable Interest Entity (VIE), including events or circumstances that could expose the reporting entity to a loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5728-111685

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5710-111685

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