EBITDA Calculation (Details) (USD $)	3 Months Ended
Mar. 31, 2014
EBITDA Calculation [Line Items]
Net income	$ 160,000
add: income tax provision	98,000
Income before income taxes	258,000
add: interest expense	209,000
add: depreciation and amortization	205,000
Earnings before interest, taxes, depreciation, and amortization	$ 672,000

Earnings before interest taxes depreciation and amortization.

No definition available.

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Earnings before interest taxes depreciation and amortization adjustments.

No definition available.

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Earnings before interest taxes depreciation and amortization income loss before income taxes.

No definition available.

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Earnings before interest taxes depreciation and amortization income tax expense benefit.

No definition available.

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Earnings before interest taxes depreciation and amortization interest expense.

No definition available.

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Earnings before interest taxes depreciation and amortization net income loss.

No definition available.

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Namespace Prefix:	hdsn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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