Name:	tmo_DebtCovenantMaximumConsolidatedTotalLeverageRatioOfDebtToEbitda
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Minimum permitted Consolidated Interest Coverage Ratio (the ratio of Consolidated EBITDA to Consolidated Interest Expense) as defined in the debt or line of credit facility agreements.

No definition available.

Name:	tmo_DebtCovenantMinimumConsolidatedInterestCoverageRatio
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Maximum maturity period allowed under U.S. commercial paper program

No definition available.

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Data Type:	xbrli:durationItemType
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Remaining period to maturity of outstanding short-term financing arrangements.

No definition available.

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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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Period Type:	instant

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The cash outflow for loan and debt issuance costs.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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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.

No definition available.

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Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_BridgeLoanMember
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Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_CommercialPaperMember
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Name:	us-gaap_DebtInstrumentAxis=tmo_U.S.CommercialPaperProgramMember
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