Fair Value Measurements - Additional Information (Detail)	3 Months Ended	12 Months Ended
Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent consideration liability, current	$ 3,326,000	$ 11,041,000
Payment of contingent consideration obligations	9,064,000
Transfers in or out Level 3, Assets	0	0
Transfers in or out Level 3, Liabilities	0	0
Transfers out of Level 1 to Level 2, Assets	0	0
Transfers into Level 1 out of Level 2, Assets	0	0
Transfers out of Level 1 to Level 2, Liabilities	0	0
Transfers into Level 1 out of Level 2, Liabilities	$ 0	0
Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Percentage of Probability Achievement of Contingent Consideration payment.	5.00%
Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Percentage of Probability Achievement of Contingent Consideration payment.	95.00%
Contingent Consideration [Member] \| Non Revenue Based Milestones [Member] \| Discount Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value measurement inputs	6.0
Creagh Medical Ltd [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Payment of contingent consideration obligations	$ 9,100,000
Contingent consideration liability	$ 11,000,000
NorMedix [Member] \| Contingent Consideration [Member] \| Revenue Based Milestones [Member] \| Discount Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value measurement inputs	20.5
Level 3 Liabilities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent consideration liability, current	$ 3,300,000	$ 11,000,000

Percentage of probability of the achievement and contingent consideration payment.

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- Definition

Value of input used to measure alternative investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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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

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy.

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Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability up to amount recognized at acquisition date, including, but not limited to, measurement period adjustment and less amount paid soon after acquisition date.

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