Acquisition - Pro forma Financial Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Business Combinations [Abstract]
Revenues	$ 242,657	$ 214,683	$ 195,741
Income before income taxes	107,316	88,361	82,769
Net income	$ 68,579	$ 61,210	$ 50,560
Basic net income per common share	$ 1.86	$ 1.68	$ 1.37
Diluted net income per common share	$ 1.81	$ 1.62	$ 1.28

Business acquisitions pro forma income loss before tax.

No definition available.

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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

+ Details

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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

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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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