Income Taxes - Summary of Company's Net Deferred Tax Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Deferred tax assets
Capital loss carryforwards	$ 7,428	$ 7,487
Stock compensation expense	7,266	6,022
Other	3,482	3,307
Total deferred tax assets	21,278us-gaap_DeferredTaxAssetsGross	21,089us-gaap_DeferredTaxAssetsGross
Valuation allowance	(7,428)	(7,743)	(727)	(287)
Net deferred tax assets	13,850us-gaap_DeferredTaxAssetsNet	13,346us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities
Depreciation and amortization	(2,461)	(1,905)
Capitalized software development costs	(4,495)	(4,163)
Intangible assets	(1,854)	(2,331)
Deferred tax assets, net	5,040	4,947
US Country [Member]
Deferred tax assets
U.S. net operating loss carryforwards	$ 3,102	$ 4,273

Deferred tax assets liabilities less foreign entity net.

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

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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 capitalized software.

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

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