Commitments and Contingencies - Additional Information (Detail)	1 Months Ended		3 Months Ended		9 Months Ended			49 Months Ended
	Aug. 31, 2018 USD ($)	Nov. 30, 2017 USD ($) ft²	Jun. 30, 2018 USD ($) € / $	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) € / $	Jun. 30, 2018 EUR (€)	Jun. 30, 2017 USD ($)	Dec. 31, 2023 USD ($)	Sep. 30, 2017 USD ($)
Commitments And Contingencies [Line Items]
License agreement commencement date					2006-03	2006-03
Annual minimum payments for licenses			$ 4,104,000	$ 2,914,000	$ 9,908,000		$ 8,104,000
Exchange rate relating to license payment | € / $			1.16801		1.16801
Future minimum payments associated with license			$ 2,200,000		$ 2,200,000
Rent expense related to operating leases			200,000	$ 100,000	400,000		$ 200,000
Amount deposited into restricted cash account			350,000		350,000
Acquired in-process research and development			7,888,000		7,888,000
Other long-term liabilities			5,681,000		5,681,000				$ 1,938,000
Eden Prairie Minnesota [Member]
Commitments And Contingencies [Line Items]
Square feet facility | ft²		36,000
Contractual obligations		$ 4,000,000
Operating lease agreement term		10 years
Operating lease agreement commencement date		2018-05
Amount deposited into restricted cash account		$ 400,000
License [Member]
Commitments And Contingencies [Line Items]
Annual minimum payments for licenses					$ 234,000	€ 200,000
Patents [Member]
Commitments And Contingencies [Line Items]
Patent expiry date					2027-09	2027-09
Intellectual Property [Member] | Embolitech LLC [Member]
Commitments And Contingencies [Line Items]
Payments to acquire intellectual property assets			4,500,000
Installment payment beginning period					2019-12	2019-12
Installment payment ending period					2023-12	2023-12
Contingent payments upon achievement of regulatory milestones					$ 2,000,000
Contingency period ending year					2033	2033
Acquired in-process research and development			7,900,000		$ 7,900,000
Other current liabilities			500,000		500,000
Other long-term liabilities			2,900,000		2,900,000
Intellectual Property [Member] | Embolitech LLC [Member] | Scenario Forecast [Member]
Commitments And Contingencies [Line Items]
Estimated additional payment to acquire intellectual property assets	$ 500,000							$ 3,500,000
Selling, general and administrative [Member]
Commitments And Contingencies [Line Items]
Claim accrual recorded in selling, general and other administrative expenses					1,000,000
Other Accrued Liabilities [Member]
Commitments And Contingencies [Line Items]
Claim accrual recorded in other accrued liabilities			$ 1,000,000		$ 1,000,000