The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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-Name Accounting Standards Codification
-Topic 323
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-Section 50
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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

Reference 1: 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(12))
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-Name Accounting Standards Codification
-Topic 944
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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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.

+ References

No definition available.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

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- Definition

The amount of fixed manufacturing costs required to be paid during the calendar year.

+ References

No definition available.

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- Definition

The percentage of fixed costs as defined in the agreement and determined at the beginning of each calendar year that the entity is required to pay.

+ References

No definition available.

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

The percentage of manufacturing capacity that the entity has the guaranteed right to purchase up to.

+ References

No definition available.

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Namespace Prefix:	var_
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- Definition

The percentage of dpiX Holding LLC's ownership interest in dpiX LLC.

+ References

No definition available.

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Period Type:	instant

- Definition

Related Party Transaction, Number Of Consortium Members

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Related Party Transactions - Additional Information (Detail) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2013	Sep. 30, 2016 USD ($) member	Oct. 02, 2015 USD ($)	Sep. 26, 2014 USD ($)
Related Party Transaction [Line Items]
Carrying value of the equity investment		$ 49.3	$ 49.7
dpiX \| Affiliated Entity
Related Party Transaction [Line Items]
Ownership interest in dpiX Holding LLC		40.00%
Number of members \| member		2
dpiX Holding LLC's ownership interest in dpiX LLC (as a percent)		100.00%
Income (Loss) on equity investment in affiliate		$ (1.5)	0.1	$ (0.8)
Carrying value of the equity investment		47.2	47.3
Purchases of glass transistor arrays from dpiX		23.4	$ 21.3	$ 20.9
Percentage of manufacturing capacity	50.00%
Percentage of fixed costs	50.00%
Fixed cost commitments		$ 4.5