| SEGMENT REPORTING AND GEOGRAPHIC INFORMATION (Tables)
 | 9 Months Ended | 
| Mar. 31, 2021 | 
|---|
| Segment Reporting [Abstract] |  | 
| Summary of Results for Reportable Segments | The following is a summary of results for each of our four reportable segments for the indicated periods: 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  | Three Months Ended |  | Nine Months Ended |  
|  | March 31, |  | March 31, |  
| (In thousands) | 2021 |  | 2020 |  | 2021 |  | 2020 |  
| Semiconductor Process Control: |  |  |  |  |  |  |  |  
| Revenues | $ | 1,506,140 |  |  | $ | 1,177,777 |  |  | $ | 4,154,278 |  |  | $ | 3,588,839 |  |  
| Segment gross margin | 982,511 |  |  | 752,649 |  |  | 2,681,411 |  |  | 2,290,721 |  |  
| Specialty Semiconductor Process: |  |  |  |  |  |  |  |  
| Revenues | 91,724 |  |  | 85,083 |  |  | 271,264 |  |  | 229,328 |  |  
| Segment gross margin | 51,720 |  |  | 47,187 |  |  | 152,819 |  |  | 126,684 |  |  
| PCB, Display and Component Inspection: |  |  |  |  |  |  |  |  
| Revenues | 205,202 |  |  | 160,411 |  |  | 565,646 |  |  | 525,242 |  |  
| Segment gross margin | 100,311 |  |  | 71,163 |  |  | 275,064 |  |  | 229,769 |  |  
| Other: |  |  |  |  |  |  |  |  
| Revenues | 149 |  |  | 469 |  |  | 739 |  |  | 3,217 |  |  
| Segment gross margin | 40 |  |  | (271) |  |  | (68) |  |  | 499 |  |  
| Totals: |  |  |  |  |  |  |  |  
| Revenues for reportable segments | $ | 1,803,215 |  |  | $ | 1,423,740 |  |  | $ | 4,991,927 |  |  | $ | 4,346,626 |  |  
| Segment gross margin | $ | 1,134,582 |  |  | $ | 870,728 |  |  | $ | 3,109,226 |  |  | $ | 2,647,673 |  |  | 
| Schedule of Reconciliation of Total Reportable Segments Revenue to Total Revenue | The following table reconciles total revenues for reportable segments to total revenues for the indicated periods: 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  | Three Months Ended |  | Nine Months Ended |  
|  | March 31, |  | March 31, |  
| (In thousands) | 2021 |  | 2020 |  | 2021 |  | 2020 |  
| Total revenues for reportable segments | $ | 1,803,215 |  |  | $ | 1,423,740 |  |  | $ | 4,991,927 |  |  | $ | 4,346,626 |  |  
| Corporate allocations and effects of foreign exchange rates | 558 |  |  | 224 |  |  | 1,336 |  |  | 205 |  |  
| Total revenues | $ | 1,803,773 |  |  | $ | 1,423,964 |  |  | $ | 4,993,263 |  |  | $ | 4,346,831 |  |  | 
| Schedule of Reconciliation of Total Segment Gross Margin to Total Income Before Income Taxes | The following table reconciles total segment gross margin to total income before income taxes for the indicated periods: 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  | Three Months Ended |  | Nine Months Ended |  
|  | March 31, |  | March 31, |  
| (In thousands) | 2021 |  | 2020 |  | 2021 |  | 2020 |  
| Total segment gross margin | $ | 1,134,582 |  |  | $ | 870,728 |  |  | $ | 3,109,226 |  |  | $ | 2,647,673 |  |  
| 
Acquisition-related charges, corporate allocations, and effects of foreign exchange rates(1)
 | 40,438 |  |  | 36,922 |  |  | 115,887 |  |  | 128,859 |  |  
| Research and development | 238,957 |  |  | 215,433 |  |  | 687,059 |  |  | 646,764 |  |  
| Selling, general and administrative | 183,040 |  |  | 185,760 |  |  | 537,580 |  |  | 566,358 |  |  
| Goodwill impairment | — |  |  | 256,649 |  |  | — |  |  | 256,649 |  |  
| Interest expense | 39,092 |  |  | 39,231 |  |  | 117,358 |  |  | 120,053 |  |  
| Loss on extinguishment of debt | — |  |  | 22,538 |  |  | — |  |  | 22,538 |  |  
| Other expense (income), net | (7,348) |  |  | (1,004) |  |  | (269) |  |  | (5,190) |  |  
| Income before income taxes | $ | 640,403 |  |  | $ | 115,199 |  |  | $ | 1,651,611 |  |  | $ | 911,642 |  | __________________(1)Acquisition-related charges primarily include amortization of intangible assets and amortization of inventory fair value adjustments presented as part of costs of revenues. | 
| Schedule of Revenues by Geographic Region | The following is a summary of revenues by geographic region, based on ship-to location, for the indicated periods: 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| (Dollar amounts in thousands) | Three Months Ended March 31, |  | Nine Months Ended March 31, |  
| 2021 |  | 2020 |  | 2021 |  | 2020 |  
| Revenues: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| Korea | $ | 557,514 |  |  | 31 | % |  | $ | 297,687 |  |  | 21 | % |  | $ | 1,094,979 |  |  | 22 | % |  | $ | 677,085 |  |  | 16 | % |  
| Taiwan | 401,797 |  |  | 22 | % |  | 349,841 |  |  | 24 | % |  | 1,151,683 |  |  | 23 | % |  | 1,183,653 |  |  | 27 | % |  
| China | 353,393 |  |  | 20 | % |  | 352,343 |  |  | 25 | % |  | 1,221,639 |  |  | 24 | % |  | 1,079,951 |  |  | 25 | % |  
| North America | 174,728 |  |  | 10 | % |  | 159,250 |  |  | 11 | % |  | 559,712 |  |  | 11 | % |  | 499,750 |  |  | 11 | % |  
| Japan | 161,190 |  |  | 9 | % |  | 152,984 |  |  | 11 | % |  | 482,330 |  |  | 10 | % |  | 553,999 |  |  | 13 | % |  
| Europe and Israel | 95,080 |  |  | 5 | % |  | 76,021 |  |  | 5 | % |  | 278,398 |  |  | 6 | % |  | 232,870 |  |  | 5 | % |  
| Rest of Asia | 60,071 |  |  | 3 | % |  | 35,838 |  |  | 3 | % |  | 204,522 |  |  | 4 | % |  | 119,523 |  |  | 3 | % |  
| Total | $ | 1,803,773 |  |  | 100 | % |  | $ | 1,423,964 |  |  | 100 | % |  | $ | 4,993,263 |  |  | 100 | % |  | $ | 4,346,831 |  |  | 100 | % |  | 
| Schedule of Revenues by Major Products | The following is a summary of revenues by major product categories for the indicated periods: 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| (Dollar amounts in thousands) | Three Months Ended March 31, |  | Nine Months Ended March 31, |  
| 2021 |  | 2020 |  | 2021 |  | 2020 |  
| Revenues: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| Wafer Inspection | $ | 714,990 |  |  | 40 | % |  | $ | 536,318 |  |  | 38 | % |  | $ | 1,921,571 |  |  | 38 | % |  | $ | 1,590,723 |  |  | 37 | % |  
| Patterning | 399,533 |  |  | 22 | % |  | 298,973 |  |  | 21 | % |  | 1,077,977 |  |  | 22 | % |  | 970,709 |  |  | 22 | % |  
| Specialty Semiconductor Process | 76,852 |  |  | 4 | % |  | 68,815 |  |  | 5 | % |  | 222,857 |  |  | 4 | % |  | 186,626 |  |  | 4 | % |  
| PCB, Display and Component Inspection | 141,539 |  |  | 8 | % |  | 103,811 |  |  | 7 | % |  | 377,990 |  |  | 8 | % |  | 353,406 |  |  | 8 | % |  
| Services | 428,453 |  |  | 24 | % |  | 372,868 |  |  | 26 | % |  | 1,234,425 |  |  | 25 | % |  | 1,093,210 |  |  | 25 | % |  
| Other | 42,406 |  |  | 2 | % |  | 43,179 |  |  | 3 | % |  | 158,443 |  |  | 3 | % |  | 152,157 |  |  | 4 | % |  
| Total | $ | 1,803,773 |  |  | 100 | % |  | $ | 1,423,964 |  |  | 100 | % |  | $ | 4,993,263 |  |  | 100 | % |  | $ | 4,346,831 |  |  | 100 | % |  | 
| Schedule of Long-Lived Assets by Geographic Region | 
Land, property and equipment, net by geographic region as of the dates indicated below were as follows: 
 
|  |  |  |  |  |  |  |  |  |  |  |  |  
|  | As of |  | As of |  
| (In thousands) | March 31, 2021 |  | June 30, 2020 |  
| Land, property and equipment, net: |  |  |  |  
| United States | $ | 419,581 |  |  | $ | 329,558 |  |  
| Singapore | 73,403 |  |  | 54,946 |  |  
| Europe | 56,016 |  |  | 58,065 |  |  
| Israel | 55,849 |  |  | 59,162 |  |  
| Rest of Asia | 23,589 |  |  | 18,093 |  |  
| Total | $ | 628,438 |  |  | $ | 519,824 |  |  |