Schedule of Components of Deferred Tax Assets Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Line Items]
Tax credits	$ 87,595	$ 79,480
Accruals	33,156	25,424
Pension liabilities	28,348	24,459
Inventory valuations	18,427	18,572
Lease liability	12,627	13,093
Deferred revenue	9,235	7,622
Equity compensation	6,543	7,042
Vacation accrual	5,890	4,768
Investment impairment	3,292	3,292
Net operating loss carryforwards	1,823	2,705
Other	626	187
Gross deferred tax assets	207,562	186,644
Less: valuation allowance	(84,962)	(77,177)
Total deferred tax assets	122,600	109,467
Depreciation	(14,525)	(18,238)
Intangible assets	(12,726)	(16,705)
Right of use assets	(10,688)	(11,197)
Contingent consideration	(3,515)
Marketable securities	(3,344)	(1,601)
Other	(710)	(611)
Total deferred tax liabilities	(45,508)	(48,352)
Net deferred assets	$ 77,092	$ 61,115

Deferred tax assets tax deferred expense lease liability.

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Deferred tax liabilities contingent consideration.

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Deferred tax liabilities right of use assets.

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Income Tax Disclosure [Line Items]

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensated absences (includes, but not limited to, sick and personal days).

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from pension benefits.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated impairment losses.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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Amount of deferred tax liability attributable to taxable temporary differences classified as other.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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