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.

+ Details

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- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

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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

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14435-108349

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-Publisher FASB
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-Topic 450
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14557-108349

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12021-110248

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585

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Balance Type:	credit
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Commitments and Contingencies - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2019	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Commitments to extend credit to commercial customers				$ 8,900,000,000	$ 8,600,000,000
Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program				3,800,000,000	$ 3,400,000,000
Payment of legal settlement expense		$ 200,000,000
Legal expenses	$ 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				$ 50,000,000