EBITDA Calculation (Details) (USD $)	9 Months Ended
Sep. 30, 2014
EBITDA Calculation [Line Items]
Net income	$ 360,000
add: income tax provision	143,000
Income before income taxes	503,000
add: interest expense	494,000
add: depreciation and amortization	626,000
Earnings before interest, taxes, depreciation, and amortization	$ 1,623,000

Earnings before interest taxes depreciation and amortization.

No definition available.

Name:	hdsn_EarningsBeforeInterestTaxesDepreciationAndAmortization
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Data Type:	xbrli:monetaryItemType
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Earnings before interest taxes depreciation and amortization adjustments.

No definition available.

Name:	hdsn_EarningsBeforeInterestTaxesDepreciationAndAmortizationAdjustments
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

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

No definition available.

Name:	hdsn_EarningsBeforeInterestTaxesDepreciationAndAmortizationIncomeLossBeforeIncomeTaxes
Namespace Prefix:	hdsn_
Data Type:	xbrli:monetaryItemType
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Earnings before interest taxes depreciation and amortization income tax expense benefit.

No definition available.

Name:	hdsn_EarningsBeforeInterestTaxesDepreciationAndAmortizationIncomeTaxExpenseBenefit
Namespace Prefix:	hdsn_
Data Type:	xbrli:monetaryItemType
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Earnings before interest taxes depreciation and amortization interest expense.

No definition available.

Name:	hdsn_EarningsBeforeInterestTaxesDepreciationAndAmortizationInterestExpense
Namespace Prefix:	hdsn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Earnings before interest taxes depreciation and amortization net income loss.

No definition available.

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

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Balance Type:	na
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