Goodwill and other intangible assets, net - Changes in carrying amount of goodwill, by reporting segment (Details) $ in Thousands	6 Months Ended
Jul. 01, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 2,235,592
Goodwill related to acquisitions	579
Currency translation adjustment	(15,283)
Goodwill, ending balance	2,220,888
Vascular North America
Goodwill [Roll Forward]
Goodwill, beginning balance	264,869
Goodwill related to acquisitions	0
Currency translation adjustment	0
Goodwill, ending balance	264,869
Interventional North America
Goodwill [Roll Forward]
Goodwill, beginning balance	433,049
Goodwill related to acquisitions	422
Currency translation adjustment	(1,938)
Goodwill, ending balance	431,533
Anesthesia North America
Goodwill [Roll Forward]
Goodwill, beginning balance	157,289
Goodwill related to acquisitions	0
Currency translation adjustment	(395)
Goodwill, ending balance	156,894
Surgical North America
Goodwill [Roll Forward]
Goodwill, beginning balance	250,912
Goodwill related to acquisitions	0
Currency translation adjustment	0
Goodwill, ending balance	250,912
EMEA
Goodwill [Roll Forward]
Goodwill, beginning balance	494,548
Goodwill related to acquisitions	9
Currency translation adjustment	(9,836)
Goodwill, ending balance	484,721
Asia
Goodwill [Roll Forward]
Goodwill, beginning balance	209,200
Goodwill related to acquisitions	3
Currency translation adjustment	(2,352)
Goodwill, ending balance	206,851
OEM
Goodwill [Roll Forward]
Goodwill, beginning balance	4,883
Goodwill related to acquisitions	0
Currency translation adjustment	0
Goodwill, ending balance	4,883
All Other
Goodwill [Roll Forward]
Goodwill, beginning balance	420,842
Goodwill related to acquisitions	145
Currency translation adjustment	(762)
Goodwill, ending balance	$ 420,225

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

+ Details

Name:	us-gaap_Goodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillAcquiredDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillForeignCurrencyTranslationGainLoss
Namespace Prefix:	us-gaap_
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.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=tfx_VascularNorthAmericaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=tfx_InterventionalNorthAmericaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=tfx_AnesthesiaNorthAmericaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=tfx_SurgicalNorthAmericaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_EMEAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=srt_AsiaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=tfx_OemMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_AllOtherSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: