Share-Based Compensation (Schedule of Selected Financial Impact of Share-Based Compensation) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 25,157	$ 23,517	$ 19,891
Income tax benefit resulting from share-based compensation expense	(4,190)	(6,810)	(6,143)
Net share-based compensation expense included in consolidated statements of income, excluding tax benefit from settlement of share-based awards	20,967	16,707	13,748
Income tax benefit resulting from settlement of share-based awards under ASU 2016-09	(21,496)	(27,743)	0
Net (benefit) expense related to share-based compensation arrangements included in consolidated statements of income	(529)	(11,036)	13,748
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	2,816	2,675	2,305
Operating expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 22,341	$ 20,842	$ 17,586

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

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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- Definition

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.

+ References

No definition available.

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