Segment Reporting and Geographic Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Jun. 30, 2011
Segment Reporting and Geographic Information
Concentration Risk, Percentage	10.00%
Revenues	$ 796,476	$ 682,342
Segment percent of total revenue	100.00%	100.00%
Long-lived assets	352,275		353,652
Number of customers with significant revenue	2	2
Number of customers with significant accounts receivable balance	2		2
Defect inspection
Segment Reporting and Geographic Information
Revenues	443,633	410,113
Segment percent of total revenue	56.00%	60.00%
Metrology
Segment Reporting and Geographic Information
Revenues	182,012	119,554
Segment percent of total revenue	23.00%	18.00%
Service
Segment Reporting and Geographic Information
Revenues	146,220	131,733
Segment percent of total revenue	18.00%	19.00%
Other
Segment Reporting and Geographic Information
Revenues	24,611	20,942
Segment percent of total revenue	3.00%	3.00%
United States
Segment Reporting and Geographic Information
Revenues	198,243	86,519
Segment percent of total revenue	25.00%	12.00%
Long-lived assets	205,763		202,520
Taiwan
Segment Reporting and Geographic Information
Revenues	223,289	188,541
Segment percent of total revenue	28.00%	28.00%
Long-lived assets	838		803
Japan
Segment Reporting and Geographic Information
Revenues	134,815	93,888
Segment percent of total revenue	17.00%	14.00%
Long-lived assets	4,265		4,256
Europe & Israel
Segment Reporting and Geographic Information
Revenues	92,996	39,246
Segment percent of total revenue	12.00%	6.00%
Long-lived assets	87,298		90,163
Korea
Segment Reporting and Geographic Information
Revenues	79,598	162,091
Segment percent of total revenue	10.00%	24.00%
Long-lived assets	2,648		2,804
Rest of Asia
Segment Reporting and Geographic Information
Revenues	67,535	112,057
Segment percent of total revenue	8.00%	16.00%
Long-lived assets	$ 51,463		$ 53,106

Total number of customers with individual accounts receivable balances representing 10 percent or more of total accounts receivable

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Total number of significant external customers who individually generate revenue that accounts for 10 percent or more of total revenues

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Segment Percent Of Total Revenue

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.10-17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13537-108611

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13531-108611

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

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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

-Article 5

-Section 03

-Paragraph 1

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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- Definition

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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