Income taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefit—beginning of period	$ 3,820	$ 3,035	$ 6,662
Increase in tax positions taken during the current period	825	785	678
Increase in tax positions taken during the prior period	181	0	242
Decrease in tax positions taken during the prior period	(128)	0	0
Decrease in tax positions due to settlements	(98)	0	(4,086)
Lapse of statute of limitations	0	0	(461)
Unrecognized tax benefit—end of period	$ 4,600	$ 3,820	$ 3,035

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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