| Accounts Payable and Other Current Liabilities - Schedule of Accounts Payable and Other Current Liabilities (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Jun. 30, 2019 | 
|---|---|---|
| Accounts Payable And Other Current Liabilities [Abstract] | ||
| Trade payables to customers | $ 5,949 | $ 1,246 | 
| Advances from customers | 183,541 | 57,643 | 
| Deferred revenue | 29,633 | 1,592 | 
| Due to brokers | 9,721 | |
| Other accounts payable | 3,076 | 1,699 | 
| Accounts payable and other current liabilities | $ 231,920 | $ 62,180 | 
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- Definition Accounts payable advance from customers current. No definition available. 
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- Definition Accounts payable and other current liabilities. No definition available. 
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- Definition Accounts payable and other current liabilities. No definition available. 
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- Definition Trade payable to customers and consignor payables, Current No definition available. 
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- Definition Amount of obligations incurred classified as other, payable within one year or the normal operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount payable to correspondent broker-dealer. No definition available. 
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