Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Amount of cash inflow from sale, maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Derivative and Financial Instruments - Cost Basis to Fair Value (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost Basis	$ 534		$ 534		$ 516
Fair Value	535		535		518
Proceeds from sales and redemptions of investments in debt securities classified as available for sale	173	$ 126	320	$ 189
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost Basis	286		286		271
Fair Value	287		287		273
Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost Basis	164		164		168
Fair Value	164		164		168
U.S. Government Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost Basis	10		10		17
Fair Value	10		10		17
U.S. Government Agency Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost Basis	10		10		17
Fair Value	10		10		17
Foreign Government Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost Basis	10		10		2
Fair Value	10		10		2
Asset-backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost Basis	54		54		41
Fair Value	$ 54		$ 54		$ 41