Derivative Financial Instruments - Offsetting Derivative Financial Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Assets:
Recognized in the Condensed Consolidated Balance Sheets, Derivatives	$ 3,499	$ 1,655
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Derivatives	(756)	(417)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Collateral	(869)	(504)
Net Amount, Derivatives	1,874	734
Recognized in the Condensed Consolidated Balance Sheets, Total assets	3,499	1,655
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Derivatives, Total assets	(756)	(417)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Collateral, Total assets	(869)	(504)
Net Amount, Total assets	1,874	734
Liabilities:
Recognized in the Condensed Consolidated Balance Sheets, Derivatives	1,294	741
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Derivatives	(756)	(417)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Collateral	(103)	(97)
Net Amount	435	227
Recognized in the Condensed Consolidated Balance Sheets, Total liabilities	1,294	741
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Derivatives, Total liabilities	(756)	(417)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheets, Collateral, Total liabilities	(103)	(97)
Net Amount, Total liabilities	$ 435	$ 227

Amount, after the effects of master netting arrangements, of derivative assets, securities purchased under agreements to resell and securities borrowed. Includes assets not subject to a master netting arrangement and not elected to be offset.

Name:	us-gaap_DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowed
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after effects of master netting arrangements, of derivative assets, securities purchased under agreements to resell and securities borrowed offset against an obligation to return collateral under a master netting arrangement. Includes assets not subject to a master netting arrangement and not elected to be offset.