Fair Value Measurements and Investments - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value		$ 219
Deferred compensation plan, Liabilities	$ (1,366)	(1,255)
Liabilities fair value, Total	(36,841)	(43,955)
Spinal Kinetics [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent consideration	(35,100)	(42,700)
Other [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent consideration	(375)
Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Deferred compensation plan, Liabilities	(1,366)
Liabilities fair value, Total	(1,366)
Fair Value, Inputs, Level 3 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities fair value, Total	(35,475)
Fair Value, Inputs, Level 3 [Member] | Spinal Kinetics [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent consideration	(35,100)
Fair Value, Inputs, Level 3 [Member] | Other [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Contingent consideration	$ (375)
Equity Securities [Member] | Bone Biologics Inc
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value		$ 219