Supplemental Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Asset Impairment Charges	$ 875	$ 161
Impairment of Right-Of-Use Asset	598
Goodwill	669,060		$ 668,211
Income tax expense	1,302	13,500
Income before income taxes and equity in earnings of non-consolidated affiliates	$ 11,296	$ 15,293
Effective tax rate (percent)	11.50%	88.30%
Revenues	$ 307,585	$ 327,742
Increase (Decrease) in Accounts Receivable	$ 2,779	$ (41,148)

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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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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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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