Balance Sheet Account Details - Other current liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Balance Sheet Related Disclosures [Abstract]
Customer incentives	$ 7,165	$ 3,766
Accrued interest	442	227
Other	5,059	1,104
Total other current liabilities	$ 12,666	$ 5,097

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are due within one year or operating cycle, if longer, from the balance sheet date.

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Amounts payable to customers at the balance sheet date. The term customers generally excludes other broker-dealers; persons who are principal officers, directors, and stockholders; and persons whose securities or funds are part of the regulatory net capital of the broker-dealer. Another broker-dealer's account can be classified as a customer if the account is carried as an omnibus account in compliance with certain regulations. The accounts of principal officers, directors and stockholders may be combined in the customer captions if they are not material and the combination is disclosed in the oath that is required to accompany the annual audited FOCUS Report.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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