Loans and Loans Held for Sale - Loans by Category (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Residential — prime loans:
Total Loans	$ 86,038	$ 59,876	$ 57,381
Loans and Leases Receivable, Collateral for Secured Borrowings	68	134
Payments to Acquire Loans Held-for-investment	21,000	114
Net loans	85,180	59,080
Commercial Credit Card [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial, financial and agricultural	116	85
PCI Loans [Member]
Residential — prime loans:
Payments to Acquire Loans Held-for-investment	865	11
Discontinued Operations [Member]
Residential — prime loans:
Total Loans	1,562	1,824
Discontinued Operations [Member] \| Education Lending [Member]
Residential — prime loans:
Total Loans	1,562	1,824
Net loans	1,600	1,800
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial, financial and agricultural	39,768	31,240
Commercial real estate:
Commercial mortgage	15,111	7,959
Construction	2,345	1,053
Total commercial real estate loans	17,456	9,012
Commercial lease financing	4,685	4,020
Total loans	61,909	44,272
Consumer Loans [Member]
Commercial real estate:
Total loans	24,129	15,604
Residential — prime loans:
Real estate — residential mortgage	5,547	2,242
Home equity loans	12,674	10,335
Total residential — prime loans	18,221	12,577
Consumer direct loans	1,788	1,600
Credit cards	1,111	806
Consumer indirect loans	$ 3,009	621
Total Loans		$ 15,604

Loans and leases receivable consumer direct loans.

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Loans and leases receivable consumer indirect loans.

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Amount before allowance of commercial leases and leveraged lease transactions where the entity is long-term creditor. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes leases covered under loss sharing agreements.

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

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Amount before allowance of revolving, open-end loan, extended under a line of credit and secured by the borrower's residential property. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance of consumer mortgage. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes subordinated loans such as home equity lines of credit and loans and leases covered under loss sharing agreements.

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Amount before allowance of consumer real estate loans. Includes, but not limited to, construction financing, residential mortgage loans, and home equity lines of credit. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance of credit card loans issued to individuals. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount before allowance of commercial construction loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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Amount before allowance of loans issued to agricultural, commercial and industrial, and financial institutions. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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Amount before allowance of mortgage loans on existing land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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Amount before allowance of commercial loans issued to businesses to acquire, develop, construct, improve, or refinance land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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The cash outflow associated with purchasing loans held for investment purposes during the period.

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