STOCKHOLDERS' EQUITY: - Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	138 Months Ended
Jun. 30, 2019	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	2.1
Cost of purchase of shares	$ 2,900
Closing price of NYSE (in dollars per share)	$ 38.85
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
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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