Commitments and Contingencies - Incentive Fees (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Mar. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Carried interest still subject to contingencies	$ 1,150,751	$ 1,022,250
Incentive fees, unrecorded estimate	$ 287,688	$ 255,562

Incentive Fee Revenue, Carried Interest, Unrecorded Estimate

No definition available.

Name:	hlne_IncentiveFeeRevenueCarriedInterestUnrecordedEstimate
Namespace Prefix:	hlne_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant