Restatement of Previously Issued Condensed Consolidated Financial Statements Restated condensed consolidated cash flows (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Net income (loss)	$ 185	$ 193
Increase (decrease) in other liabilities	2	(7)
Net Cash Provided by (Used in) Operating Activities	653	512
Net Cash Provided by (Used in) Continuing Operations		(5)
Cash, cash equivalents and restricted cash at beginning of period	338	413
Cash, cash equivalents and restricted cash at end of period	$ 472	408
Previously Reported [Member]
Net income (loss)		210
Increase (decrease) in other liabilities		(24)
Net Cash Provided by (Used in) Operating Activities		512
Net Cash Provided by (Used in) Continuing Operations		(5)
Cash, cash equivalents and restricted cash at beginning of period		413
Cash, cash equivalents and restricted cash at end of period		408
Restatement Adjustment [Member]
Net income (loss)		(17)
Increase (decrease) in other liabilities		17
Net Cash Provided by (Used in) Operating Activities		0
Net Cash Provided by (Used in) Continuing Operations		0
Cash, cash equivalents and restricted cash at beginning of period		0
Cash, cash equivalents and restricted cash at end of period		0
Other Adjustment [Member]
Net income (loss)		0
Increase (decrease) in other liabilities		0
Net Cash Provided by (Used in) Operating Activities		0
Net Cash Provided by (Used in) Continuing Operations		0
Cash, cash equivalents and restricted cash at beginning of period		0
Cash, cash equivalents and restricted cash at end of period		$ 0

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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