Supplemental Information - Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Accounts Receivable, after Allowance for Credit Loss, Current	$ 377,670	$ 374,892
Goodwill	669,060	668,211
Assets	1,560,713	1,511,312
Accruals and other liabilities	242,667	274,968
Liabilities	1,940,944	1,893,085
Accumulated deficit	(704,741)	(709,751)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(405,583)	(408,910)	$ (183,944)	$ (190,575)
Liabilities and Equity	$ 1,560,713	$ 1,511,312

Accrued expenses and other current liabilities

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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