Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jan. 02, 2015	Jan. 03, 2014
Deferred tax assets:
Accrued liabilities and allowances	$ 17,244	$ 15,539
Deferred compensation	26,873	22,373
Other	28	0
Total deferred tax assets	44,145us-gaap_DeferredTaxAssetsGross	37,912us-gaap_DeferredTaxAssetsGross
Deferred tax liabilities:
State taxes	(1,717)expo_DeferredTaxLiabilitiesStateTaxes	(1,519)expo_DeferredTaxLiabilitiesStateTaxes
Deductible goodwill	(2,978)	(2,925)
Property, equipment and leasehold improvements	(459)	(622)
Unrealized gain of deferred compensation plan assets	(3,377)	(3,215)
Other	0us-gaap_DeferredTaxLiabilitiesOther	(394)us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liabilities	(8,531)us-gaap_DeferredTaxLiabilities	(8,675)us-gaap_DeferredTaxLiabilities
Net deferred tax assets	$ 35,614us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 29,237us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Liabilities State Taxes.

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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 of deferred tax liability attributable to taxable temporary differences from unrealized gains on trading securities.

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