STOCKHOLDERS' EQUITY - Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2008
SCC share repurchase program:
Amount authorized for share repurchase program	$ 3,000	$ 500
Closing price of NYSE (in dollars per share)	$ 30.77
Maximum Number of Shares that May Yet Be Purchased Under the Plan @ $30.77	2.7
Percentage of Ownership by Parent	88.90%
Parent Company (Grupo Mexico) common shares
SCC share repurchase program:
Total Number of Shares Purchased	119.5
Cost of purchase of shares	$ 2,900

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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