Pensions and Post-Employment Benefits - Schedule of Estimated Payments for Pensions and Other Post-Employment Benefits (Detail) $ in Millions	12 Months Ended
Dec. 31, 2017 MXN ($)
Disclosure - Pensions and Post-Employment Benefits - Schedule of Estimated Payments for Pensions and Other Post-Employment Benefits [Abstract]
2018	$ 3,071
2019	2,952
2020	3,085
2021	3,080
2022	3,121
2023 - 2027	$ 15,868

Disclosure - Pensions and Post-Employment Benefits - Schedule of Estimated Payments for Pensions and Other Post-Employment Benefits [Abstract]

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Estimated payments for pensions and other post employment benefits due in next twelve months.

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Estimated payments for pensions and other post employment benefits due in year five.

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Estimated payments for pensions and other post employment benefits due in year four.

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Estimated payments for pensions and other post employment benefits due in year three.

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Estimated payments for pensions and other post employment benefits due in year two.

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Estimated payments for pensions and other post employment benefits due in years six to ten.

No definition available.

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