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.

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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.

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- Definition

Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Credit Quality - Summary of the ALLL and Related Loans and Leases Classified by Portfolio Segment (Parenthetical) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses	$ 1,143	$ 1,115	$ 1,103	$ 1,091	$ 1,077	$ 1,196
Portfolio loans and leases	109,225		95,086
Residential Mortgage Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans measured at fair value on a recurring basis	184		179
Leveraged leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses	1		1
Portfolio loans and leases	$ 492		$ 624