Debt instrument additional basis spread.

No definition available.

Name:	hnna_DebtInstrumentAdditionalBasisSpread
Namespace Prefix:	hnna_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentPeriodicPaymentPrincipal
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=hnna_UsBankNationalAssociationLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=hnna_OneMonthLiborMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
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Balance Type:
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Bank Loan - Additional Information (Detail) - USD ($)		6 Months Ended
Bank Loan - Additional Information (Detail) - USD ($)	Mar. 26, 2020	Mar. 31, 2020	Mar. 31, 2019
Debt Instrument [Line Items]
Prepayments of long term debt		$ 17,500,000	$ 2,188,000
US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Required monthly loan principal repayment		$ 364,583
Prepayments of long term debt	$ 15,400,000
Minimum [Member] \| One Month Libor [Member] \| US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Debt instrument additional basis spread		2.25%
Maximum [Member] \| One Month Libor [Member] \| US Bank National Association Loan [Member]
Debt Instrument [Line Items]
Debt instrument additional basis spread		2.75%
Debt, Weighted Average Interest Rate		3.92%