Debt Instrument, Drawdown Term

No definition available.

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- Definition

Debt Instrument, Extension Term

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Debt Instrument, Number of Periodic Payments

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Debt Instrument, Periodic Payments, Term

+ References

No definition available.

+ Details

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- Definition

Interest coverage ratio.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Line of credit facility percentage of principal payment.

+ References

No definition available.

+ Details

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Namespace Prefix:	kra_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of debt guaranteed by guarantor.

+ References

No definition available.

+ Details

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Namespace Prefix:	kra_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 2: 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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Balance Type:	na
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

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

+ Details

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

- Definition

The lowest amount of net worth (total assets minus total liabilities) required by secondary market investors or state-imposed regulatory mandates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)(a)
-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47080-110998

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47304-110998

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Long-Term Debt - KFPC Loan Agreement (Details)		3 Months Ended	9 Months Ended
Long-Term Debt - KFPC Loan Agreement (Details)	Jul. 17, 2014 USD ($)	Sep. 30, 2017 USD ($) installment	Sep. 30, 2017 USD ($) installment	Dec. 31, 2019 USD ($)	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2017 TWD installment	Dec. 31, 2016 USD ($)	Jul. 17, 2014 TWD
Debt Instrument [Line Items]
Principal		$ 1,769,795,000	$ 1,769,795,000					$ 1,836,896,000
KFPC Loan Agreement
Debt Instrument [Line Items]
Credit facility, borrowing capacity		181,200,000	181,200,000						TWD 5,500,000,000.0
Principal		$ 146,451,000	$ 146,451,000				TWD 4,400,000,000	$ 115,854,000
Loan agreement term (in years)			5 years
Line of credit facility, fixed interest rate	0.80%								0.80%
Percentage added to basis	1.70%
Interest rate during period		1.80%
Minimum tangible net worth required	$ 50,000,000.0
KFPC Loan Agreement \| Kraton Polymers LLC
Debt Instrument [Line Items]
Percentage of indebtedness payable	50.00%								50.00%
KFPC Loan Agreement \| Scenario, Forecast
Debt Instrument [Line Items]
Debt to equity ratio					1.2	2
Minimum tangible net worth required				$ 100,000,000.0
Interest coverage ratio						5.0
KFPC Loan Agreement \| Tranche A
Debt Instrument [Line Items]
Credit facility, borrowing capacity		$ 141,300,000	$ 141,300,000						TWD 4,290,000,000.00
KFPC Loan Agreement \| Tranche B
Debt Instrument [Line Items]
Credit facility, borrowing capacity		$ 39,900,000	$ 39,900,000						TWD 1,210,000,000.00
KFPC Loan Agreement \| First Five Installments
Debt Instrument [Line Items]
Payment of outstanding principal amount (as a percent)	10.00%								10.00%
KFPC Loan Agreement \| Final Installment
Debt Instrument [Line Items]
Payment of outstanding principal amount (as a percent)	50.00%								50.00%
Revolving Credit Facility \| KFPC Loan Agreement
Debt Instrument [Line Items]
Loan agreement drawdown term (in months)			28 months
Loan agreement extension term (in years)			2 years
Number of semi-annual principal installments \| installment		6	6				6
Loan agreement subsequent payments, term (in months)			6 months