Property and Equipment (Detail) (USD $)	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Furniture and fixtures	$ 3,381,076	$ 3,138,617
Equipment	14,869,677	12,541,199
Purchased software	7,142,797	5,845,189
Leasehold improvements	1,042,567	810,454
Property and equipment, Gross	26,436,117	22,335,459
Less accumulated depreciation	(17,583,287)	(15,576,974)
Property and equipment, net	$ 8,852,830	$ 6,758,485

The gross amount of capitalized computer software costs as of the balance sheet date.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 985

-SubTopic 20

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- Definition

Gross amount, at the balance sheet date, of long-lived, depreciable assets commonly used in offices and stores. Examples include desks, chairs, and store fixtures.

+ References

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 5

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Gross amount, at the balance sheet date, of long-lived, depreciable assets that are an addition or improvement to assets held under lease arrangement.

+ References

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Gross amount, as of the balance sheet date, of long-lived, depreciable assets used in the production process to produce goods and services.

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-Publisher AICPA

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Gross amount, at the balance sheet date, of long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

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-Publisher SEC

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-Publisher FASB

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The cumulative amount of depreciation (related to capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy) that has been recognized in the income statement.

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No definition available.

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