Credit Agreement (Details) - USD ($) $ in Millions		9 Months Ended
Feb. 08, 2011	Sep. 30, 2018
Line of Credit Facility [Line Items]
Available revolving credit		485515
Bank Of America February Two Thousand Eleven New Credit Agreement
Line of Credit Facility [Line Items]
Revolving line of credit	500000
Letters of credit outstanding		$ 14.5

Description of unused borrowing capacity under the debt instrument and conditions under which the commitment can be withdrawn by the lender.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
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Balance Type:	na
Period Type:	duration

- Definition

Describes when borrowings outstanding under a line of credit will convert to a term loan, and describes the repayment terms, collateral, and priority (seniority) of the term loan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=flir_BankOfAmericaFebruaryTwoThousandElevenNewCreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: