Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

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- Definition

The gains (losses) recognised in other comprehensive income on cash flow hedges, net of tax. [Refer: Cash flow hedges [member]]

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The amount of income tax relating to amounts recognised in other comprehensive income in relation to cash flow hedges. [Refer: Cash flow hedges [member]; Other comprehensive income]

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- Definition

A component of equity representing the accumulated portion of gain (loss) on a hedging instrument that is determined to be an effective hedge for cash flow hedges. [Refer: Cash flow hedges [member]]

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Financial Instruments - Reconciliation Per Category of Equity Components and Analysis of OCI Components, Net of Tax Generated by Cash Flow Hedges (Detail) - MXN ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of detailed information about hedged items [line items]
Taxes due to changes in reserves during the period	$ (293)	$ (191)	$ 745
Hedging reserve [member]
Disclosure of detailed information about hedged items [line items]
Balances at beginning of the period	1,384
Taxes due to changes in reserves during the period	294
Balances at the end of the period	812	1,384
Hedging reserve [member] \| Foreign exchange currency risk [member] \| Purchase of stock [member]
Disclosure of detailed information about hedged items [line items]
Fair value changes	(132)
Hedging reserve [member] \| Foreign exchange currency risk [member] \| Other stock [member]
Disclosure of detailed information about hedged items [line items]
Fair value changes	(462)
Hedging reserve [member] \| Interest rate risk [member]
Disclosure of detailed information about hedged items [line items]
Fair value changes	(273)
Cost of hedging reserve [member]
Disclosure of detailed information about hedged items [line items]
Balances at beginning of the period	12
Balances at the end of the period	24	$ 12
Cost of hedging reserve [member] \| Foreign exchange currency risk [member] \| Purchase of stock [member]
Disclosure of detailed information about hedged items [line items]
Fair value changes	$ 12