Allowance for commercial unfunded loan commitments and letters of credit

No definition available.

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- Definition

Reclassification of Equity Securities from Nommarketable to Marketable

+ References

No definition available.

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- Definition

Unfunded Commercial Loan Commitments and Letters of Credit

+ References

No definition available.

+ Details

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

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Fair Value Measurement and Election - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Transfer of Portfolio Loans and Leases to Held-for-sale	$ 123	$ 67	$ 327	$ 127
Loans Receivable, Fair Value Disclosure	177		177		$ 196
Unfunded loan commitments and letters of credit	69,000		69,000		66,400
Allowance for unfunded loan commitments and letters of credit	75		75		84
Reclassification of Equity Securities from Nommarketable to Marketable			22
Fair Value, Inputs, Level 1 [Member]
Loans Receivable, Fair Value Disclosure	0		0		0
Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	0		0		0
Fair Value, Inputs, Level 3 [Member]
Loans Receivable, Fair Value Disclosure	177		177		196
Total Return Swap [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	1,600		1,600		1,700
Interest Rate Lock Commitments [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	23	$ 70	17	$ 106
Trading Account Assets [Member] \| SBA Loans [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	285		285		368
Trading Account Assets [Member] \| Commercial and Corporate Leveraged Loans [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	86		86		48
Fair Value, Measurements, Recurring [Member]
Loans Receivable, Fair Value Disclosure	177		177		196
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Loans Receivable, Fair Value Disclosure	0		0		0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	0		0		0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans Receivable, Fair Value Disclosure	$ 177		$ 177		$ 196