Noninterest Expense (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure Noninterest Expense [Abstract]
Staff	$ 5,733	$ 5,837	$ 5,845
Professional, legal and other purchased services	1,185	1,230	1,339
Software	647	627	620
Net occupancy	590	600	610
Distribution and servicing	405	381	428
Furniture and equipment	247	280	322
Sub-custodian	245	270	286
Business development	245	267	268
Bank Assessment Charges	219	157	146
Clearing	155	150	129
Communications	87	103	119
Other	479	551	637
Amortization of intangible assets	237	261	298
Litigation	45	87	953
Merger and integration and restructuring charges	4	(2)	177
Total noninterest expense	$ 10,523	$ 10,799	$ 12,177

Bank Assessment Charges

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Disclosure - Noninterest Expense [Abstract]

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- Definition

Expenses incurred for post-merger integration of operations including personnel, benefit plans, premises, equipment, computer systems, service contracts, system conversion costs, employee retention arrangements and costs of incremental communications to customers and others. Restructuring charges relate to amounts charged against earnings in the period for incurred and estimated costs, excluding asset retirement obligations, associated with exit from or disposal of business activities or restructurings pursuant to a program that is planned and controlled by management, and materially changes either the scope of business undertaken by an entity, or the manner in which that business is conducted. Also includes credit adjustments of prior amounts charged against earnings.

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- Definition

Noninterest Expense, Other

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No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
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Business development involves the development of products and services, their delivery, design and their implementation. Business development includes a number of techniques designed to grow an economic enterprise. Such techniques include, but are not limited to, assessments of marketing opportunities and target markets, intelligence gathering on customers and competitors, generating leads for possible sales, follow-up sales activity, formal proposal writing and business model design. Business development involves evaluating a business and then realizing its full potential, using such tools as marketing, sales, information management and customer service.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(6))
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- Definition

The amount of expense incurred in the period for communication, which is the exchange of information by several methods.

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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-03.6)
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- Definition

This element represents equipment expense including depreciation, repairs, rentals, and service contract costs. This item also includes equipment purchases which do not qualify for capitalization in accordance with the entity's accounting policy. This item may also include furniture expenses.

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No definition available.

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- Definition

Expense related to distribution, servicing and underwriting fees.

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- Definition

The amount of expense during the period for floor brokerage fees paid to other broker-dealers to execute trades on their behalf, stock exchange fees, order flow fees, and clearance fees.

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No definition available.

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- Definition

The amount of expenses incurred in the period for information technology and data processing products and services.

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-Publisher FASB
-Name Accounting Standards Codification
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The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense.

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The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

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- Definition

Total aggregate amount of all noninterest expense.

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Fees paid to an agent employed by a corporation or mutual fund to maintain shareholder records, including purchases, sales, and account balances. Also includes custodian fees incurred during an accounting period from an agent, bank, trust company, or other organization that holds and safeguards an individual's, mutual fund's, or investment company's assets for them. These fees will be billed back to the client and are a component of noninterest expense.

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- Definition

Amount of net occupancy expense that may include items, such as depreciation of facilities and equipment, lease expenses, property taxes and property and casualty insurance expense.

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-Publisher FASB
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A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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