STOCKHOLDERS' EQUITY: - Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	153 Months Ended
Sep. 30, 2020	Dec. 31, 2008
SCC share repurchase program:
Amount authorized for share repurchase program	$ 3,000	$ 500
Number of Shares Purchased	119.5
Maximum Number of Shares that May Yet Be Purchased Under the Plan @ $39.68	1.8
Cost of purchase of shares	$ 2,900
Closing price of NYSE (in dollars per share)	$ 45.27
Percentage of ownership by parent	88.90%

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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