Share-Based Compensation (Schedule of Selected Financial Impact of Share-Based Compensation) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 30,951	$ 39,278	$ 25,157
Income tax benefit resulting from share-based compensation expense	(3,965)	(4,861)	(4,190)
Net share-based compensation expense included in consolidated statements of income, excluding tax benefit from settlement of share-based awards	26,986	34,417	20,967
Income tax benefit resulting from settlement of share-based awards	(38,981)	(19,140)	(21,496)
Net expense (benefit) related to share-based compensation arrangements included in consolidated statements of income	(11,995)	15,277	(529)
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	3,415	2,681	2,816
Operating expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 27,536	$ 36,597	$ 22,341

Allocated Share-based Compensation Expense, Net of Tax, Excluding Tax Benefit From Settlement Of Share-based Awards

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount, after tax, of expense for award under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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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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