Acquisitions (Schedule Of Supplemental Unaudited Pro Forma Financial Information) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Acquisitions [Abstract]
Total revenues	$ 257,837	$ 252,013
Net income	$ 11,096	$ 12,257
Basic net income per basic share	$ 0.24	$ 0.26
Shares used in computing net income per basic share	46,932	47,425
Diluted net income per diluted share	$ 0.23	$ 0.25
Shares used in computing net income per diluted share	48,969	49,031

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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