Supplemental Disclosures of Cash Flow (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Disclosures of Cash Flow Data [Abstract]
Interest paid	$ 281	$ 281	$ 248
Income taxes paid (received)	260	90	$ 170
Significant non-cash investing and financing transactions:
Reduction of other investments in connection with the expiration of a repurchase agreement	$ (150)
Investments received in financing transactions		$ 263

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of assets, classified as other, acquired in a noncash or part noncash acquisition.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References

No definition available.

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Value of investments transferred from the entity's investments in noncash transactions.

+ References

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