Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Segment Reporting Information [Line Items]
Sales	$ 699,871	$ 567,104	$ 1,345,180	$ 1,101,545
Gross Profit	377,063	301,947	727,159	581,512
Unallocated corporate general and administrative expenses	13,726	11,127	26,946	22,635
Industrial Technology
Segment Reporting Information [Line Items]
Sales	183,455	145,490	353,437	280,802
Percent change in Net Sales	26.1		25.9
Gross Profit	92,068	73,930	177,782	141,442
Percent change in Gross Profit	24.5		25.7
Operating Profit	51,729	38,742	97,918	70,508
Percent change in Operating Profit	33.5		38.9
Long-lived assets	41,343	41,033	41,343	41,033
Percent change in Long-lived assets	0.8
Energy Systems And Controls
Segment Reporting Information [Line Items]
Sales	145,750	119,387	275,383	225,065
Percent change in Net Sales	22.1		22.4
Gross Profit	80,412	64,803	150,558	118,294
Percent change in Gross Profit	24.1		27.3
Operating Profit	37,704	29,072	66,748	47,995
Percent change in Operating Profit	29.7		39.1
Long-lived assets	17,868	19,311	17,868	19,311
Percent change in Long-lived assets	(7.5)
Medical And Scientific Imaging
Segment Reporting Information [Line Items]
Sales	151,078	128,514	296,365	258,758
Percent change in Net Sales	17.6		14.5
Gross Profit	95,006	78,307	186,260	155,817
Percent change in Gross Profit	21.3		19.5
Operating Profit	35,352	27,796	70,389	57,130
Percent change in Operating Profit	27.2		23.2
Long-lived assets	48,261	35,670	48,261	35,670
Percent change in Long-lived assets	35.3
RF Technology
Segment Reporting Information [Line Items]
Sales	219,588	173,713	419,995	336,920
Percent change in Net Sales	26.4		24.7
Gross Profit	109,577	84,907	212,559	165,959
Percent change in Gross Profit	29.1		28.1
Operating Profit	52,911	34,704	97,861	66,905
Percent change in Operating Profit	52.5		46.3
Long-lived assets	$ 31,047	$ 31,154	$ 31,047	$ 31,154
Percent change in Long-lived assets	(0.3)

The percent change in aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity, from the previous period to the current period.

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The percent change in total revenue from sales of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances and sales discounts, from the previous period to the current period.

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The percent change in the total amount of profit or loss for reportable segments, from the previous period to the current period.

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The percent change in total assets for reportable segments, from the previous period to the current period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Article 5

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of an item in the reconciliation of total profit or loss from reportable segments, to the entity's consolidated income before income taxes, extraordinary items, discontinued operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 32
-Subparagraph b

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Total assets for reportable segments.

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-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 32
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The total amount of profit or loss for reportable segments.

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-Name Statement of Financial Accounting Standard (FAS)
-Number 131
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