Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Components Of Income Tax Expense Benefit [Line Items]
Corporate income tax rate			21.00%	21.00%	35.00%
Additional income tax expense benefit		$ 8,300
Tax cuts and jobs act of 2017 change in tax rate deferred tax assets and liability expected to reserve in future					$ 8,600
Change of intention for foreign earnings					0
Tax cuts and jobs act of 2017 change in provisional income tax benefit					300
Impact of the Tax Act	$ (600)			$ (560)	8,347
Cash paid related to taxes			$ 8,100	15,600	3,300
Net decrease in valuation allowance			10,300
Unremitted foreign earnings			$ 49,200	50,400
Minimum percentage of income tax benefit			50.00%
Gross unrecognized tax benefit			$ 16,900	21,400
Net interest and penalties on unrecognized tax benefits			(100)	1,400	2,300
Accrued interest and penalties related to unrecognized tax benefits			6,600	6,700
Income taxes			1,413	$ 9,074	$ 29,100
Internal Revenue Service [Member]
Components Of Income Tax Expense Benefit [Line Items]
Income taxes			(1,800)
Minimum [Member]
Components Of Income Tax Expense Benefit [Line Items]
Decrease in unrecognized tax benefits, exclusive of interest and penalties			13,000
Maximum [Member]
Components Of Income Tax Expense Benefit [Line Items]
Decrease in unrecognized tax benefits, exclusive of interest and penalties			13,500
State [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax			$ 35,500
Operating loss carryforwards, expiration year			2020
State [Member] | Spinal Kinetics [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax			$ 22,000
Federal [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax			$ 25,500
Operating loss carryforwards, expiration year			2026
Research and development credits			$ 1,600
Foreign Tax Authority
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax			$ 145,300
Operating loss carryforwards, expiration year			2020