Pensions and Post-Employment Benefits - Schedule of Estimated Payments for Pensions and Other Post-Employment Benefits (Detail) $ in Millions	12 Months Ended
Dec. 31, 2018 MXN ($)
Disclosure - Pensions and Post-Employment Benefits - Schedule of Estimated Payments for Pensions and Other Post-Employment Benefits [Abstract]
2019	$ 2,904
2020	2,663
2021	2,641
2022	2,662
2023 - 2028	$ 15,714

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 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 Five To Ten

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