Changes in Carrying Amount of Intangible Assets (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible asset carrying amount, beginning balance	$ 14,524,500	$ 11,791,500
Intangible asset carrying amount, business acquisition		2,733,000
Intangible asset carrying amount, ending balance	14,524,500	14,524,500
Intangible asset accumulated amortization, beginning balance	(3,385,879)	(1,520,642)
Intangible asset, accumulated amortization	(2,058,226)us-gaap_AmortizationOfIntangibleAssets	(1,865,237)us-gaap_AmortizationOfIntangibleAssets
Intangible asset accumulated amortization, ending balance	(5,444,105)	(3,385,879)
Intangible asset beginning balance, net	11,138,621us-gaap_FiniteLivedIntangibleAssetsNet	10,270,858us-gaap_FiniteLivedIntangibleAssetsNet
Intangible asset business acquisition, net		2,733,000
Intangible asset ending balance, net	$ 9,080,395us-gaap_FiniteLivedIntangibleAssetsNet	$ 11,138,621us-gaap_FiniteLivedIntangibleAssetsNet

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, resulting from a business combination.

+ References

No definition available.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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