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Related Party Transactions - Additional Information (Details) - USD ($) $ in Millions			1 Months Ended	12 Months Ended			27 Months Ended
	Jul. 01, 2016	Aug. 13, 2014	Sep. 30, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016
Orthotec LLC, litigation settlement
Related Party Transaction [Line Items]
Payments of settlement						$ 17.5	$ 27.4
Judgment assessed by court for (against) company		$ (49.0)
Orthotec LLC, litigation settlement \| Indemnification Agreement
Related Party Transaction [Line Items]
Indemnification obligation payments (less than $0.1 million)				$ 0.1	$ 0.1	0.1
Orthotec LLC, litigation settlement \| HealthpointCapital, LLC
Related Party Transaction [Line Items]
Payments of settlement	$ 1.0			1.1
Judgment assessed by court for (against) company			$ (5.0)
HealthpointCapital, LLC
Related Party Transaction [Line Items]
Incurred expenses (less than $.1 million)				0.1	$ 0.1	$ 0.2
Payable liability (less than $.1 million)				$ 0.1			$ 0.1