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

The net investment in arrangements meeting the criteria to be classified as leveraged.

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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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Credit Quality (Summary of the ALLL and Related Loans and Leases Classified by Portfolio Segment) (Parenthetical) (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses
Allowance for loan and lease losses	$ 2,348	$ 1,202	$ 1,115	$ 1,103
Leveraged leases	379	429
Leveraged Leases
Financing Receivable, Allowance for Credit Losses
Allowance for loan and lease losses	4	1
Residential Mortgage Loans
Financing Receivable, Allowance for Credit Losses
Portfolio loans and leases at fair value	$ 185	$ 183