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 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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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
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	$ 11,854,000,000		$ 13,706,000,000
Loss on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring		$ 0
Collateral receivable			1,000,000
Pledged collateral, securities	91,000,000		78,000,000
Cash collateral held	37,000,000		16,000,000
Securities Received as Collateral	2,000,000		1,000,000
Collateral Securities Repledged, Delivered, or Used	0		0
Fair Value of Securities Received as Collateral that Have Been Resold or Repledged	0		0
Over the Counter [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pledged collateral, securities	113,000,000		88,000,000
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
AOCI Attributable to Parent [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	38,000,000
Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	$ 9,227,000,000		11,396,000,000
Not Designated as Hedging Instrument \| Interest rate swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount			$ 7,600,000,000