Orthotec Settlement - Additional Information (Details) - Orthotec LLC, litigation settlement $ in Thousands			1 Months Ended		6 Months Ended
	Oct. 01, 2014 USD ($)	Aug. 13, 2014 USD ($) installment	Apr. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Jun. 30, 2017 USD ($)
Loss Contingencies [Line Items]
Judgment assessed by court for (against) company		$ (49,000)
Payments of settlement			$ 15,750	$ 1,750	$ 29,600
Number of quarterly installments | installment		28
Litigation settlement interest, quarterly installments, amount		$ 1,100
Litigation settlement, final installment amount		700
Litigation settlement, remaining outstanding balance including interest					$ 28,200
Beginning fourth quarter of 2014
Loss Contingencies [Line Items]
Settlement amount, remaining balance	$ 31,500
Litigation settlement interest, quarterly installments, amount		$ 1,100
Litigation settlement interest rate		7.00%
Litigation settlement payments, quarterly payment amount		$ 1,100
Final installment
Loss Contingencies [Line Items]
Number of quarterly installments | installment		1