Gains (losses) from operating activities in the statement of income by function of expenses, included according to their nature (Details 9) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest expense from bank borrowings and overdrafts		$ (1,707)	$ (1,650)	$ (1,847)
Interest expense from bonds		(55,887)	(49,373)	(55,563)
Interest expense from loans		(3,093)	(2,002)	(4,419)
Capitalized interest expenses		5,021	4,382	5,406
Financial Expenses For Site Closure		(960)	0	0
Other finance costs		(3,288)	(1,481)	(1,075)
Total	$ (50,124)	$ (59,914)	$ (50,124)	$ (57,498)

The amount of expense arising from interest.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2018-01-01
-Paragraph 23
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_23_d&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2018-01-01
-Paragraph 28
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_28_e&doctype=Standard
-URIDate 2018-03-16

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2018-01-01
-Paragraph B13
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_B13_f&doctype=Appendix&seq=2
-URIDate 2018-03-16

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of interest expense on bank loans and overdrafts. [Refer: Interest expense; Bank overdrafts]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard
-URIDate 2018-03-16

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of interest expense on bonds issued. [Refer: Interest expense; Bonds issued]

+ References

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of interest expense on borrowings. [Refer: Interest expense; Borrowings]

+ References

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of interest expense on other financial liabilities. [Refer: Interest expense; Other financial liabilities]

+ References

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of capitalized interest expenses during the year.

+ References

No definition available.

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Balance Type:	debit
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- Definition

The amount represents financial expenses for site closure during the period.

+ References

No definition available.

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Namespace Prefix:	sqm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration