Business Segment Information - Reconciliation of Segment Profit to Income Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Reconciliation of segment profit to income before income taxes
Income before income taxes	$ 34,838	$ 970
Stock compensation expense	6,057	9,607
Depreciation and amortization	28,684	30,708
Interest expense	9,029	9,107
Interest and other income	(3,759)	(4,974)
Segment Profit (Loss)	$ 74,849	$ 45,562

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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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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The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of noncash expense for share-based payment arrangement.

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