Segment Information, Operating Results by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue [Abstract]
Revenue	$ 339,186	$ 363,041	$ 686,699	$ 719,518
Operating income (loss)	47,368	52,181	96,788	107,862
Interest expense	5,200	5,555	10,602	11,110
Earnings before income taxes	42,168	46,626	86,186	96,752
Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	174,534	191,818	353,278	374,300
Operating income (loss)	20,050	24,001	43,175	49,328
Interest expense	0	0	0	0
Earnings before income taxes	20,050	24,001	43,175	49,328
Color [Member]
Revenue [Abstract]
Revenue	135,650	140,702	275,900	284,430
Operating income (loss)	27,877	31,133	58,076	64,805
Interest expense	0	0	0	0
Earnings before income taxes	27,877	31,133	58,076	64,805
Asia Pacific [Member]
Revenue [Abstract]
Revenue	29,002	30,521	57,521	60,788
Operating income (loss)	4,201	4,634	8,419	9,506
Interest expense	0	0	0	0
Earnings before income taxes	4,201	4,634	8,419	9,506
Reportable Segments [Member]
Revenue [Abstract]
Revenue	348,048	373,470	703,999	739,243
Reportable Segments [Member] \| Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	180,134	198,658	363,687	387,004
Reportable Segments [Member] \| Color [Member]
Revenue [Abstract]
Revenue	138,912	144,291	282,791	291,451
Reportable Segments [Member] \| Asia Pacific [Member]
Revenue [Abstract]
Revenue	29,002	30,521	57,521	60,788
Intersegment Revenue [Member]
Revenue [Abstract]
Revenue	(8,862)	(10,429)	(17,300)	(19,725)
Intersegment Revenue [Member] \| Flavors & Fragrances [Member]
Revenue [Abstract]
Revenue	(5,600)	(6,840)	(10,409)	(12,704)
Intersegment Revenue [Member] \| Color [Member]
Revenue [Abstract]
Revenue	(3,262)	(3,589)	(6,891)	(7,021)
Intersegment Revenue [Member] \| Asia Pacific [Member]
Revenue [Abstract]
Revenue	0	0	0	0
Corporate & Other [Member]
Revenue [Abstract]
Revenue	0	0	0	0
Operating income (loss)	(4,760)	(7,587)	(12,882)	(15,777)
Interest expense	5,200	5,555	10,602	11,110
Earnings before income taxes	$ (9,960)	$ (13,142)	$ (23,484)	$ (26,887)

No definition available.

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

- Definition

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (210.5-03(11))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.9)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

+ Details

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

- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

Name:	us-gaap_OperatingIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

+ Details

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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

- Details

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

- Details

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

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_IntersegmentEliminationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidationItemsAxis=us-gaap_CorporateNonSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: