Commitments Contingencies And Guarantees [Line Items]

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- Definition

Compliance period of property.

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- Definition

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

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- Definition

Remaining actual life letters of credit.

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Remaining weighted-average life of standby letters of credit.

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- Definition

Rental Expense Under All Operating Leases

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- Definition

Weighted average life of written put options.

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- Definition

Weighted Average Loan to Value, Ratio

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- Definition

Weighted-average remaining term for outstanding commercial mortgage loans.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
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- Definition

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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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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 - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments Contingencies And Guarantees [Line Items]
Rental expense under all operating leases	$ 118	$ 122	$ 123
Minimum future rental payments under noncancelable operating leases due in 2017	149
Minimum future rental payments under noncancelable operating leases due in 2018	133
Minimum future rental payments under noncancelable operating leases due in 2019	115
Minimum future rental payments under noncancelable operating leases due in 2020	98
Minimum future rental payments under noncancelable operating leases due in 2021	83
Minimum future rental payments under noncancelable operating leases, all subsequent years	390
Default guarantees, value	115
Written Put Options [Member]
Commitments Contingencies And Guarantees [Line Items]
Default guarantees, value	$ 35
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	$ 67
Underwriting And Servicing Program [Member]
Commitments Contingencies And Guarantees [Line Items]
Weighted-average remaining term for outstanding commercial mortgage loans in years	7 years 6 months
Unpaid principal balance outstanding of loans sold	$ 8,600
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding	29.00%
Default guarantees, value	$ 5
Residential Mortgage Reserve [Member]
Commitments Contingencies And Guarantees [Line Items]
Unpaid principal balance outstanding of loans sold	$ 4,200
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)	71.00%
Default guarantees, value	$ 5
Return Guarantee Agreement with LIHTC Investors [Member]
Commitments Contingencies And Guarantees [Line Items]
Default guarantees, value	$ 3
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	30 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%