This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

+ Details

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- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

+ Details

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- Definition

Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 15
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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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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Redeemable Noncontrolling Interest- Additional Information (Details) $ in Thousands, £ in Millions	6 Months Ended
	Jun. 29, 2018 USD ($)	Jan. 10, 2017 USD ($)	Jan. 10, 2017 GBP (£)	Dec. 31, 2016
Minority Interest [Line Items]
Adjustment of redeemable noncontrolling interest to estimated redemption value	$ 5,096
Laser Quantum
Minority Interest [Line Items]
Percentage of equity interest held before acquisition				41.00%
Percentage of equity interest held after acquisition		76.00%	76.00%
Initial fair value of noncontrolling interest		$ 21,600	£ 17.7