Basis of Presentation - Corporate Reorganization (Details) - Subsequent Event $ / shares in Units, $ in Millions	Aug. 06, 2019 USD ($) $ / shares shares
Conversion of Stock [Line Items]
Number of shares exchanged for common stock (in shares) \| shares	1,000
Par value (in dollars per share) \| $ / shares	$ 1
Common Stock
Conversion of Stock [Line Items]
Shares exchanged for common stock	$ (221)
Additional Paid-in Capital
Conversion of Stock [Line Items]
Shares exchanged for common stock	$ 221

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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration