Accruals and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
CSS deposits	$ 169,216	$ 110,291
Accrued benefits	41,322	36,613
Accrued compensation	26,721	22,131
Due to customers	13,408	9,869
Accrued acquisition stay bonus	8,630	5,599
Deferred compensation plan liabilities	7,306	169
Contingent consideration from acquisitions	6,900	2,884
Accrued cloud provisioning costs	6,546	7,988
Non-contingent consideration from acquisitions	5,911	685
Accrued professional fees	4,146	4,210
Accrued indirect taxes	3,510	6,361
Employee stock purchase plan contributions	2,589	0
Accrued facility costs	2,153	2,095
Accrued severance and realignment costs	1,337	7,209
Other accrued and current liabilities	17,576	10,689
Accruals and other current liabilities	$ 317,271	$ 226,793

Accrued Cloud Provisioning Costs, Current

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Accrued Facility Costs, Current

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Business Combination, Consideration Payable, Current

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Due to Customers

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Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements. 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, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. 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 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 the obligations incurred through that date and payable for employees' services provided. 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 liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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The current portion, due within one year or one operating cycle, if longer, of deposits held other than customer deposits.

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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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Amount of obligations incurred for employer-related costs classified as other, payable within one year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Carrying value as of the balance sheet date of liabilities incurred through that date and payable for statutory sales and use taxes, including value added tax. 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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