Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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The carrying value as of the balance sheet date of securities received as collateral from a counterparty that were re-pledged, sold, delivered or otherwise reused by the entity.

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Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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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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This describes information about the sources and uses of collateral that is acquired through resale agreements and securities borrowing agreements that the entity is permitted by contract or custom to sell or repledge.

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The amount of loss reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

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Derivative Instruments - Derivatives - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	$ 12,291,000,000		$ 12,361,000,000
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			18,000,000
Collateral receivable	4,000,000		1,000,000
Pledged collateral, securities	67,000,000		73,000,000
Cash collateral held	9,000,000		11,000,000
Securities Received as Collateral	5,000,000		2,000,000
Collateral Securities Repledged, Delivered, or Used	$ 0		$ 0
Securities Sold under Agreements to Repurchase, Fair Value of Collateral	did not sell any securities held as collateral.		did not sell any securities held as collateral
Over the Counter [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pledged collateral, securities	$ 89,000,000		$ 85,000,000
AOCI Attributable to Parent [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Loss on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring		$ 0	0	$ 0
AOCI Attributable to Parent [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Loss on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring			0
Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	$ 10,098,000,000		$ 10,101,000,000