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For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612

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- Definition

Fair Value Inputs Credit Valuation Adjustment As A Percentage Of Derivative Contract

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- Definition

Other guarantees carrying value excluding standby letters of credit.

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- Definition

Unfunded commitments deferred non-yield related loan fees and standby letters of credit carrying value.

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Fair Values of Assets and Liabilities - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Mortgage loans held for sale measured at fair value, net gain (loss)	$ 4	$ 28	$ 61	$ 69
Carrying value of unfunded commitments, deferred non-yield related loan fees and standby letters of credit	536		536		$ 555
Other guarantees carrying value	$ 224		$ 224		$ 192
Minimum [Member]
Fair Value Disclosures [Abstract]
Assumed credit valuation adjustment as percentage of derivative contract fair value			0.00%
Maximum [Member]
Fair Value Disclosures [Abstract]
Assumed credit valuation adjustment as percentage of derivative contract fair value			97.00%
Weighted Average [Member]
Fair Value Disclosures [Abstract]
Assumed credit valuation adjustment as percentage of derivative contract fair value			0.00%