Other balance sheet items - Schedule of Trade and Other Payables (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Trade payables	$ 22,882	$ 18,160
Advance deposits	36,058	43,884
Withholding and other taxes payable	42,780	34,904
Interest payable	270	5,586
Payroll and related accruals	13,852	13,848
Accrued expenses and other payables	20,972	23,146
Total trade and other payables	$ 136,814	$ 139,528

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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Carrying value as of the balance sheet date of obligations incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Carrying value as of the balance sheet date of obligations incurred and payable for statutory payroll taxes incurred through that date and withheld from employees pertaining to services received from them, including entity's matching share of the employees FICA taxes and contributions to the state and federal unemployment insurance programs.

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Amount of liabilities incurred and payable to vendors for goods and services received classified as other, and expenses incurred but not yet paid, payable within one year or the operating cycle, if longer.

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No definition available.

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