Basis of Presentation - Corporate Reorganization (Details) $ / shares in Units, $ in Millions	Aug. 01, 2019 USD ($) $ / shares shares	Jul. 31, 2019
Conversion of Stock [Line Items]
Reorganization, shareholders conversion ratio		1
Number of shares exchanged for common stock (in shares) \| shares	100
Par value (in dollars per share) \| $ / shares	$ 1
Common Stock
Conversion of Stock [Line Items]
Reorganization reclassification amount	$ (221)
Additional Paid-in Capital
Conversion of Stock [Line Items]
Reorganization reclassification amount	$ 221

Number of shares issued during the period as a result of the conversion of convertible securities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Balance Type:	na
Period Type:	duration