Business Combinations, Pro Forma Information (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Business Acquisition, Pro Forma Information [Abstract]
Revenues	$ 341,983	$ 339,194
Net income	$ 20,298	$ 19,780
Basic net income per share	$ 0.62	$ 0.62
Diluted net income per share	$ 0.61	$ 0.59
Shares used in computing basic net income per share	32,683	32,025
Shares used in computing diluted net income per share	33,332	33,303

Business acquisition proforma weighted average shares outstanding basic.

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- Definition

Business acquisition proforma weighted average shares outstanding diluted.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

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=25497992&loc=d3e1392-128463

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- Definition

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.

+ References

+ Details

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- Definition

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.

+ References

+ Details

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- Definition

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

+ References

+ Details

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