Cover	12 Months Ended
	Dec. 31, 2020 USD ($) shares
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	000-21918
Entity Registrant Name	FLIR Systems, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	93-0708501
Entity Address, Address Line One	27700 SW Parkway Avenue,
Entity Address, City or Town	Wilsonville,
Entity Address, State or Province	OR
Entity Address, Postal Zip Code	97070
City Area Code	503
Local Phone Number	498-3547
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	FLIR
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float | $	$ 5,279,054,662
Entity Common Stock, Shares Outstanding | shares	131,238,445
Entity Central Index Key	0000354908
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false