Income taxes (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended		12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2017
Income Taxes [Abstract]
Income tax provision (benefit)		$ (921)	$ (26)	$ (1,386)	$ 89
Effective tax rate		33.20%	(16.30%)	32.80%	8.70%
U.S. corporate income tax rate				21.00%		34.00%
Unrecognized tax benefits that would favorably affect effective income tax rate if recognized		$ 107		$ 107
Accrued interest and penalties related to uncertain tax positions		$ 24		$ 24
Forecast [Member]
Income Taxes [Abstract]
Unrecognized tax benefits that will lapse upon expiration of statute of limitations	$ 27