Schedule of Components of Net Deferred Tax Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Deferred Tax Assets and Liabilities [Line Items]
Valuation allowance	$ (2,616)
Carry-forward losses of subsidiaries	364	9
Minimum alternate tax credit of subsidiaries	27,233	20,457
Property, plant and equipment	344	801
Accrued expenses and allowances	12,071	8,893
Total deferred tax assets	37,396us-gaap_DeferredTaxAssetsGross	30,160us-gaap_DeferredTaxAssetsGross
Provision for branch tax on dividend equivalent in India	(1,726)	(1,726)
Provision for tax on unrealized gains in India	(2,307)	(1,872)
Total deferred tax liabilities	(4,033)us-gaap_DeferredTaxLiabilities	(3,598)us-gaap_DeferredTaxLiabilities
Net deferred tax assets	$ 33,363us-gaap_DeferredTaxAssetsNet	$ 26,562us-gaap_DeferredTaxAssetsNet

Deferred Tax Liabilities Tax On Dividend Equivalent

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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 after 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 other deductible loss carryforwards not separately disclosed.

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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 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 unrealized gains on foreign currency transactions.

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