This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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-Publisher FASB
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Amount of the cumulative effect on retained earnings net of related income tax effect.

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Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

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Summary Of Significant Accounting Policies (Recent Accounting Pronouncements) (Details) - USD ($) $ in Thousands		12 Months Ended			48 Months Ended
	Jan. 01, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect on Retained Earnings, Net of Tax	$ 100
Payments Related to Tax Withholding for Share-based Compensation		$ 4,229	$ 4,451	$ 9,211
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Acquisition costs					$ 200
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Acquisition costs					$ 2,400