Bank borrowings - Maturities of Short-tem and Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019
Debt Disclosure [Abstract]
2020	$ 30,616
2021	26,396
2022	37,004
2023	22,694
2024	14,550
Total principal of debt	131,260
Less: debt issuance costs	(1,371)
Total principal of debt, less debt issuance costs	129,889
Short-term Debt
Principal amount	30,613
Less: debt issuance costs	(499)
Total debt, less debt issuance costs	30,114
Long-term Debt
Principal amount	100,647
Less: debt issuance costs	(872)
Principal amount	$ 99,775	$ 59,380

Long-term And Short-term Debt, Maturities, Repayments Of Principal In Next Twelve Months

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Long-term Debt, Current Maturities, And Short-Term Debt, Gross

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Long-term Debt, Current Maturities, And Short-term Debt

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, before accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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