Employee benefits, Net cost for period (Details) - MXN ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Details for net cost [Abstract]
Interest cost	$ (225)	$ (140)
Net cost for the period	21,211	21,284
Pensions and Seniority Premiums [Member]
Details for net cost [Abstract]
Current service cost	4,114	5,460
Interest cost	12,994	12,015
Net cost for the period	17,108	17,475
Termination of Employment [Member]
Details for net cost [Abstract]
Current service cost	1,858	1,868
Interest cost	2,245	1,941
Net cost for the period	$ 4,103	$ 3,809

No definition available.

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- Definition

The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2018-01-01
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+ Details

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- Definition

The increase (decrease) in the net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2018-01-01
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- Definition

The increase (decrease) in the net defined benefit liability (asset) resulting from the passage of time. [Refer: Interest expense; Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details

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- Details

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