Other accrued expenses and other non-current liabilities - Other non-current liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Other Liabilities, Noncurrent [Abstract]
Leasehold obligation incentive	$ 7,750
Deferred Rent	2,592	$ 272
Deferred tax liabilities	2,818
Other	5	6
Total non-current liabilities	$ 13,165	$ 278

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date.

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This item represents the deferred credit for an incentive or inducement received by a lessee from a lessor, in order to motivate the lessee to enter the lease agreement, which incentive or inducement is to be recognized as a reduction of rental expense over the lease term.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

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