Non-controlling interest (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Noncontrolling Interest [Line Items]
Units (in shares)	21,326,621				21,682,792				21,326,621	21,682,792
Ownership percentage	100.00%				100.00%				100.00%	100.00%
Noncontrolling Interest [Roll Forward]
Beginning balance				$ 6,118				$ 5,502	$ 6,118	$ 5,502
Allocation of income to non-controlling LLC Unit holders for period	$ 307	$ 1,088	$ 876	$ 823	$ 1,073	$ 1,104	$ 741	$ 717	3,094	3,635	$ 3,356
Distributions paid and payable to non-controlling LLC Unit holders for period									(1,370)	(1,845)
Reallocation of non-controlling interest									(895)	(1,174)
Ending balance	$ 6,947				$ 6,118				$ 6,947	6,118	5,502
Common units, canceled (in shares)									15,733
Tax distributions payable to non-controlling LLC Unit holders									$ 104	$ 568	511
Repurchase Agreements [Member]
Noncontrolling Interest [Roll Forward]
Stock repurchased during period (in shares)									483,679
Class A Common Stock
Noncontrolling Interest [Roll Forward]
Shares issued during period (in shares)									242,741
Stock repurchased during period (in shares)									483,679	0
Non-controlling LLC unit holders ownership in Malibu Boats Holdings, LLC
Noncontrolling Interest [Line Items]
Units (in shares)	730,652				830,152				730,652	830,152
Ownership percentage	3.40%				3.80%				3.40%	3.80%
Noncontrolling Interest [Roll Forward]
Tax distributions payable to non-controlling LLC Unit holders									$ 104	$ 568
Distribution paid to noncontrolling interests									$ 1,836	$ 1,785	$ 1,647
Malibu Boats, Inc. ownership in Malibu Boats Holdings, LLC
Noncontrolling Interest [Line Items]
Units (in shares)	20,595,969				20,852,640				20,595,969	20,852,640
Ownership percentage	96.60%				96.20%				96.60%	96.20%