Property and Equipment, Net (Detail) - Property And Equipment, Net (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 9,363us-gaap_PropertyPlantAndEquipmentGross	$ 7,926us-gaap_PropertyPlantAndEquipmentGross
Less: Accumulated depreciation and amortization	(5,212)	(3,259)
Total property and equipment, net	4,151us-gaap_PropertyPlantAndEquipmentNet	4,667us-gaap_PropertyPlantAndEquipmentNet
Internal-use software
Property, Plant and Equipment [Line Items]
Internal-use software	5,358	4,198
Leasehold improvements
Property, Plant and Equipment [Line Items]
Leasehold improvements	1,799	1,700
Computer, equipment and software
Property, Plant and Equipment [Line Items]
Computer, equipment and software	1,221	1,096
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Furniture and fixtures	818	813
Construction-in-progress
Property, Plant and Equipment [Line Items]
Construction-in-progress	$ 167	$ 119

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

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-Paragraph 1

-Subparagraph (a)

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

+ References

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- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

+ References

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- Definition

Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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