Accrued interest fees and other amounts due.

No definition available.

Name:	hgen_AccruedInterestFeesAndOtherAmountsDue
Namespace Prefix:	hgen_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The percentage of accrued interest payments.

+ References

No definition available.

+ Details

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Namespace Prefix:	hgen_
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Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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Namespace Prefix:	hgen_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument floating interest rate, deduction, rate.

+ References

No definition available.

+ Details

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Namespace Prefix:	hgen_
Data Type:	dtr:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Repayment of term loan.

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

The average effective interest rate during the reporting period.

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- Definition

Aggregate amount of interest paid or due on all long-term debt.

+ References

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Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Period Type:	instant

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Period Type:	duration

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Namespace Prefix:
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Period Type:

Debt (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Debt (Details) - USD ($) $ in Millions	Jul. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Mar. 29, 2021	Mar. 10, 2021
Debt (Details) [Line Items]
Accrued interest percentage		8.75%
Interest expense		$ 1.2
Secured Term Loan Facility [Member]
Debt (Details) [Line Items]
Principal amount					$ 80.0
Draw amount				$ 25.0
Net proceeds		$ 24.4
Prime rate, percentage		8.75%
Floating interest rate, deduction		3.25%
Repayment of term loan	$ 25.0
Accrued interest	$ 1.7
Interest expense		$ 2.9	$ 2.3
Effective interest rate		9.30%	9.00%