Capital lease interest rate.

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Amount of damages paid to the plaintiff in the legal matter.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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The amount the entity has committed to make for future royalty guarantees.

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Commitments and Contingencies - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Loss Contingencies [Line Items]
Rent expense	$ 300,000	$ 300,000	$ 600,000	$ 1,000,000
Lawsuit expense recorded					$ 100,000
Liability in connection with lawsuit	0		0
Alphatec Spine, Inc.
Loss Contingencies [Line Items]
Guaranteed obligated minimum royalty payments through 2022 and beyond	$ 5,900,000		$ 5,900,000
Minimum
Loss Contingencies [Line Items]
Lease interest rate			6.40%
Maximum
Loss Contingencies [Line Items]
Lease interest rate			7.64%