Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Components Of Income Tax Expense Benefit [Line Items]
Corporate income tax rate				21.00%	35.00%	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	$ 1,300
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				15,600	3,300	4,400
Change in estimate, increase in net income						$ 2,400
Change in estimate, increase in earnings per share						$ 0.13
Net increase in valuation allowance				2,700
Unremitted foreign earnings		335,700		$ 50,400	335,700
Minimum percentage of income tax benefit				50.00%
Gross unrecognized tax benefit		22,500		$ 21,400	22,500
Net interest and penalties on unrecognized tax benefits				1,400	2,300	$ 2,100
Accrued interest and penalties related to unrecognized tax benefits		$ 5,300		6,700	5,300
Income taxes				9,074	$ 29,100	$ 15,527
Scenario, Forecast [Member]
Components Of Income Tax Expense Benefit [Line Items]
Income taxes			$ (2,000)
Minimum [Member]
Components Of Income Tax Expense Benefit [Line Items]
Decrease in unrecognized tax benefits				3,300
Maximum [Member]
Components Of Income Tax Expense Benefit [Line Items]
Decrease in unrecognized tax benefits				3,800
State [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax				49,000
State [Member] | Spinal Kinetics [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax				35,200
Foreign Jurisdictions [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax				159,500
Federal [Member]
Components Of Income Tax Expense Benefit [Line Items]
Operating loss carry forwards, net of tax				24,400
Research and development credits				$ 1,600