Debt Instrument, Exchange Period

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Margin Adjustment

+ References

No definition available.

+ Details

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Namespace Prefix:	hli_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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LOANS PAYABLE (Details) - USD ($)			1 Months Ended	12 Months Ended
LOANS PAYABLE (Details) - USD ($)	Aug. 31, 2020	Aug. 23, 2019	Dec. 31, 2019	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021	May 31, 2018	Apr. 30, 2018
Loans Payable \| Non Interest Bearing Unsecured Convertible Loan
Debt Instrument [Line Items]
Loans payable, face amount	$ 4,500,000			$ 12,900,000	$ 20,300,000			$ 10,500,000
Interest and unused commitment fees paid				22,000	162,000	$ 288,000
Exchange period	3 years
Loans Payable \| Two Point Eighty Eight Percent Loans Payable
Debt Instrument [Line Items]
Loans payable, face amount							$ 2,800,000
Interest and unused commitment fees paid				18,000	105,000	105,000
Stated interest rate							2.88%
Loans Payable \| Two Point Seven Five Percent Loans Payable
Debt Instrument [Line Items]
Loans payable, face amount			$ 4,000,000
Interest and unused commitment fees paid				81,000	79,000	$ 103,000
Stated interest rate			2.75%
Exchange period			4 years
Revolving line of credit \| Bank of America
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity		$ 100,000,000
Margin adjustment		1.00%
Principal outstanding				0
Revolving line of credit \| Bank of America \| 2019 Line of Credit, Expansion Option
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity		$ 200,000,000
Baylor Klein, Ltd
Debt Instrument [Line Items]
Contingent consideration				$ 18,100,000	$ 17,600,000
Secured Overnight Financing Rate (SOFR) \| Revolving line of credit \| Bank of America
Debt Instrument [Line Items]
Stated interest rate on line of credit		0.10%
Fed Funds Effective Rate Overnight Index Swap Rate \| Revolving line of credit \| Bank of America
Debt Instrument [Line Items]
Stated interest rate on line of credit		0.50%