Commitments to extend credit to commercial customers.

No definition available.

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- Definition

Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in loss contingency liability.

+ References

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-Publisher FASB
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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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Commitments and Contingencies - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2018
Loss Contingencies [Line Items]
Commitments to extend credit to commercial customers	$ 8,700,000,000			$ 8,600,000,000
Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program	3,500,000,000			$ 3,400,000,000
Payment of legal settlement expense		$ 200,000,000
Increased recorded liability for legal-related matters	50,000,000		$ 135,000,000
Minimum [Member]
Loss Contingencies [Line Items]
Range of reasonably possible losses	0
Maximum [Member]
Loss Contingencies [Line Items]
Range of reasonably possible losses	$ 100,000,000