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Depreciation as percentage of total cost of revenue.

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Latest effective date of minimum liquidity covenant, month and year.

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Minimum liquidity covenant amount.

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Proceeds from issuance or sale of equity, gross.

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Working capital.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

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The Company and Basis of Presentation - Additional Information (Details) $ in Thousands		12 Months Ended
	Mar. 08, 2018 USD ($)	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)	Mar. 27, 2019 USD ($)	Nov. 06, 2018 USD ($)
Company And Basis Of Presentation [Line Items]
Number of reportable segments \| segment		1
Working capital		$ 44,900
Cash		29,054	$ 22,466
Net proceeds from equity offering	$ 51,900
Minimum liquidity covenant amount		$ 5,000
Latest effective date of minimum liquidity covenant		2020-03
Depreciation		$ 6,000	6,600
Reclassification \| Surgical instruments
Company And Basis Of Presentation [Line Items]
Depreciation		$ 5,300	$ 5,900
Percentage of total cost of revenues		15.00%	15.00%
Term Loan \| Squadron Credit Agreement
Company And Basis Of Presentation [Line Items]
Secured debt agreement		$ 35,000			$ 35,000
Term Loan \| Squadron Credit Agreement \| Subsequent Event
Company And Basis Of Presentation [Line Items]
Secured debt agreement				$ 30,000