Consolidated Statements of Stockholders' Equity (Parenthetical) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) $ / shares
Cash dividends (in dollars per share) \| $ / shares	$ 2.3800
Other comprehensive income (loss), net of tax	$ 26
Pension and Other Postretirement Benefit Plans
Other comprehensive income (loss), net of tax	2
Pension and Other Postretirement Benefit Plans \| SCS
Other comprehensive income (loss), net of tax	27
Other comprehensive income (loss), tax	$ 9

Amount after tax and reclassification adjustments of other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-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 220
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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