Accrued Liabilities and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Payroll and other employee related costs	$ 27,920	$ 19,014
Professional services, consulting and other vendor fees	20,382	17,461
Unrecognized tax benefits	2,053	1,913
Sales commissions	9,654	6,239
Contingent earn-out (Note 8)	557	2,372
Restructuring Reserve	314	977	$ 2,338
Other	1,898	2,686
Total	$ 62,778	$ 50,662

Contingent earnout liability.

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for sales commissions. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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