Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Segment Reporting Information [Line Items]
Sales	$ 712,705	$ 605,088	$ 2,057,885	$ 1,706,633
Gross Profit	382,556	321,749	1,109,715	903,261
Unallocated corporate general and administrative expenses	14,860	13,680	41,806	36,315
Industrial Technology
Segment Reporting Information [Line Items]
Sales	185,258	161,205	538,695	442,007
Percent change in Net Sales	14.9		21.9
Gross Profit	91,238	82,383	269,020	223,825
Percent change in Gross Profit	10.7		20.2
Operating Profit	52,238	44,954	150,156	115,462
Percent change in Operating Profit	16.2		30.0
Long-lived assets	41,070	40,754	41,070	40,754
Percent change in Long-lived assets	0.8
Energy Systems And Controls
Segment Reporting Information [Line Items]
Sales	150,385	123,458	425,768	348,523
Percent change in Net Sales	21.8		22.2
Gross Profit	81,832	65,590	232,390	183,884
Percent change in Gross Profit	24.8		26.4
Operating Profit	38,675	28,611	105,423	76,606
Percent change in Operating Profit	35.2		37.6
Long-lived assets	17,784	18,731	17,784	18,731
Percent change in Long-lived assets	(5.1)
Medical And Scientific Imaging
Segment Reporting Information [Line Items]
Sales	156,470	134,434	452,835	393,192
Percent change in Net Sales	16.4		15.2
Gross Profit	99,035	82,610	285,295	238,427
Percent change in Gross Profit	19.9		19.7
Operating Profit	38,610	31,193	108,999	88,323
Percent change in Operating Profit	23.8		23.4
Long-lived assets	46,940	35,458	46,940	35,458
Percent change in Long-lived assets	32.4
RF Technology
Segment Reporting Information [Line Items]
Sales	220,592	185,991	640,587	522,911
Percent change in Net Sales	18.6		22.5
Gross Profit	110,451	91,166	323,010	257,125
Percent change in Gross Profit	21.2		25.6
Operating Profit	52,552	37,155	150,413	104,060
Percent change in Operating Profit	41.4		44.5
Long-lived assets	$ 29,879	$ 34,319	$ 29,879	$ 34,319
Percent change in Long-lived assets	(12.9)

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

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-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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 32

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Total assets for reportable segments.

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-Name Statement of Financial Accounting Standard (FAS)

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The total amount of profit or loss for reportable segments.

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