Acquisitions - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended
Nov. 05, 2014	Dec. 31, 2014
Number Of Employees	32hdsn_NumberOfEmployees
Purchase price for aquisition	$ 8,035,000
Tangible assets	5,435,000
Intangible assets	2,335,000
Goodwill	265,000
Professional Fees		$ 163,000us-gaap_ProfessionalFees
Minimum [Member]
Intangible assets amotized period	2 years
Maximum [Member]
Intangible assets amotized period	10 years

Number of employees.

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472

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-Name Accounting Standards Codification

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-07.2(a),(b),(c),(d))

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-SubTopic 225

-Section 45

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