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Commitments, Contingent Liabilities and Guarantees - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Commitments Contingencies And Guarantees [Line Items] |
Default guarantees, value | $ 118
Written Put Options [Member] |
Commitments Contingencies And Guarantees [Line Items] |
Default guarantees, value | $ 32
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 8 months 12 days
Unpaid principal balance outstanding of loans sold | $ 16,500
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding | 30.00%
Default guarantees, value | $ 7
Residential Mortgage Reserve [Member] |
Commitments Contingencies And Guarantees [Line Items] |
Unpaid principal balance outstanding of loans sold | $ 6,100
Maximum potential amount of undiscounted future payments that could be required, percentage of principal balance of loans outstanding | 30.00%
Default guarantees, value | $ 7
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 | 0.00%
Minimum [Member] | Moderate [Member] |
Commitments Contingencies And Guarantees [Line Items] |
Guarantee obligations, probability of payment | 30.00%
Minimum [Member] | High [Member] |
Commitments Contingencies And Guarantees [Line Items] |
Guarantee obligations, probability of payment | 70.00%
Maximum [Member] | Standby Letters of Credit [Member] |
Commitments Contingencies And Guarantees [Line Items] |
Remaining actual life letters of credit in years | 15 years
Maximum [Member] | Low [Member] |
Commitments Contingencies And Guarantees [Line Items] |
Guarantee obligations, probability of payment | 30.00%
Maximum [Member] | Moderate [Member] |
Commitments Contingencies And Guarantees [Line Items] |
Guarantee obligations, probability of payment | 70.00%

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- Definition Guarantor Obligations, Maximum Exposure, Undiscounted as Percentage of Total Loans Outstanding + References No definition available. + Details
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- Definition Remaining actual life letters of credit. + References No definition available. + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248 + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248 + Details
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- Definition 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). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25383-109308 + Details
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