Warranty Obligations (Details) (USD $) In Millions	6 Months Ended
Jul. 02, 2011	Jul. 03, 2010
Warranty Obligation Roll Forward
Beginning Balance	$ 41.7	$ 45.2
Provision charged to income	24.6	20.9
Usage	(27.3)	(20.5)
Acquisitions	2.9	0.2
Adjustments to previously provided warranties, net	(0.3)	0.2
Other, net	1.9	(2.0)
Ending Balance	$ 43.5	$ 44.0

Total increase (decrease) in the standard and extended product warranty liability due to currency translation and other items, net.

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Namespace Prefix:	tmo
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 15
-Subparagraph 5
-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9, 10

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Total liability for standard and extended product warranties acquired in a business acquisition.

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents the aggregate increase (decrease) in the liability during the reporting period for accruals related to preexisting standard and extended product warranties (including adjustments for changes in estimates).

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
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- Definition

Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.

+ Details

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