Orthotec Settlement - Additional Information (Details) - Orthotec LLC, litigation settlement $ in Millions				1 Months Ended	12 Months Ended		27 Months Ended
	Jul. 01, 2016 USD ($)	Oct. 01, 2014 USD ($)	Aug. 13, 2014 USD ($) installment	Sep. 30, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)
Loss Contingencies [Line Items]
Judgment assessed by court for (against) company			$ (49.0)
Payments of settlement						$ 17.5	$ 27.4
Number of quarterly installments | installment			28
Litigation settlement interest, quarterly installments, amount			$ 1.1
Litigation settlement, final installment amount			0.7
Loss contingency accrual					$ 30.4		$ 30.4
HealthpointCapital, LLC
Loss Contingencies [Line Items]
Judgment assessed by court for (against) company				$ (5.0)
Payments of settlement	$ 1.0				$ 1.1
Beginning fourth quarter of 2014
Loss Contingencies [Line Items]
Settlement amount, remaining balance		$ 31.5
Litigation settlement interest, quarterly installments, amount			$ 1.1
Litigation settlement interest rate			7.00%
Litigation settlement payments, quarterly payment amount			$ 1.1
Final installment
Loss Contingencies [Line Items]
Number of quarterly installments | installment			1