Pro Forma Results Under Acquisition (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013 ZTEC Instruments, Inc.	Dec. 31, 2012 ZTEC Instruments, Inc.	Dec. 31, 2011 Litepoint Corporation
Business Acquisition, Pro Forma Information [Line Items]
Revenue	$ 1,431,270	$ 1,660,758	$ 1,527,044
Income from continuing operations			357,060
Net income	$ 163,394	$ 215,654	$ 382,976
Income from continuing operations per common share, basic			$ 1.93
Income from continuing operations per common share, diluted			$ 1.56
Net income per common share, basic	$ 0.86	$ 1.15	$ 2.07
Net income per common share, diluted	$ 0.69	$ 0.94	$ 1.67

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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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