Commitments Contingencies And Guarantees [Line Items]

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Compliance period of property.

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Guarantor Obligations, Maximum Exposure, Undiscounted as Percentage of Total Loans Outstanding

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Remaining actual life letters of credit.

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Remaining weighted-average life of standby letters of credit.

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Rental Expense Under All Operating Leases

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Weighted average life of written put options.

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Weighted Average Loan to Value, Ratio

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Weighted-average remaining term for outstanding commercial mortgage loans.

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- Definition

Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Indicates, if estimable, (as a percentage) the approximate extent to which the proceeds from liquidation of any assets held either as collateral or by third parties would be expected to cover the maximum potential amount of future payments under the guarantee or each group of similar guarantees.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Commitments, Contingent Liabilities and Guarantees - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commitments Contingencies And Guarantees [Line Items]
Rental expense under all operating leases	$ 149	$ 153	$ 118
Minimum future rental payments under noncancelable operating leases due in 2019	142
Minimum future rental payments under noncancelable operating leases due in 2020	133
Minimum future rental payments under noncancelable operating leases due in 2021	118
Minimum future rental payments under noncancelable operating leases due in 2022	104
Minimum future rental payments under noncancelable operating leases due in 2023	90
Minimum future rental payments under noncancelable operating leases, all subsequent years	321
Default guarantees, value	174
Written Put Options [Member]
Commitments Contingencies And Guarantees [Line Items]
Default guarantees, value	$ 88
Weighted average life of written put options	3 years
Standby Letters of Credit [Member]
Commitments Contingencies And Guarantees [Line Items]
Remaining weighted-average life of standby letters of credit in years	2 years
Default guarantees, value	$ 72
Underwriting And Servicing Program [Member]
Commitments Contingencies And Guarantees [Line Items]
Weighted-average remaining term for outstanding commercial mortgage loans in years	7 years 10 months 24 days
Unpaid principal balance outstanding of loans sold	$ 14,100
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding	29.00%
Default guarantees, value	$ 6
Residential Mortgage Reserve [Member]
Commitments Contingencies And Guarantees [Line Items]
Unpaid principal balance outstanding of loans sold	$ 5,200
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding	30.00%
Weighted average loan to value ratio (as a percentage)	74.00%
Liability for estimated repurchase obligations on loans sold	$ 6
Return Guarantee Agreement with LIHTC Investors [Member]
Commitments Contingencies And Guarantees [Line Items]
Default guarantees, value	$ 2
Compliance period of property	15 years
Default Guarantees [Member]
Commitments Contingencies And Guarantees [Line Items]
Default guarantees, value	$ 1
Minimum [Member] \| Standby Letters of Credit [Member]
Commitments Contingencies And Guarantees [Line Items]
Remaining actual life letters of credit in years	1 year
Minimum [Member] \| Low [Member]
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment (percentage)	0.00%
Minimum [Member] \| Moderate [Member]
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment (percentage)	30.00%
Minimum [Member] \| High [Member]
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment (percentage)	70.00%
Maximum [Member] \| Standby Letters of Credit [Member]
Commitments Contingencies And Guarantees [Line Items]
Remaining actual life letters of credit in years	16 years
Maximum [Member] \| Low [Member]
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment (percentage)	30.00%
Maximum [Member] \| Moderate [Member]
Commitments Contingencies And Guarantees [Line Items]
Guarantee obligations, probability of payment (percentage)	70.00%