Contingent consideration measurement period.

No definition available.

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- Definition

business acquisition, assets under management acquired

+ References

No definition available.

+ Details

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- Definition

Gain (Loss) on Disposition of Business, Net of Tax

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Ownership percentage prior to acquisition

+ References

No definition available.

+ Details

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Namespace Prefix:	bk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

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Balance Type:	na
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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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Balance Type:	debit
Period Type:	duration

- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2443-110228

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51719941&loc=d3e2941-110230

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of write-off of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit associated with the sale of all or a portion of a reporting unit.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585

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Balance Type:	credit
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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Acquisitions and dispositions- Additional Information (Detail) - USD ($)							12 Months Ended
	Jul. 31, 2015	Jan. 02, 2015	May. 01, 2014	Apr. 23, 2014	Sep. 27, 2013	May. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Acquisitions
Contingent payments							$ 0
Potential obligation to pay additional consideration, upper limit							$ 4,000,000
Contingent consideration arrangement time period of measurement							3 months
Goodwill							$ 17,618,000,000	$ 17,869,000,000	$ 18,073,000,000
Dispositions
Dispositions, net of cash							$ 17,000,000	$ 64,000,000	$ 84,000,000
Meriten Investment Management GmbH
Dispositions
Dispositions, net of cash	$ 40,000,000
After-tax gain (loss) on sale	(12,000,000)
Goodwill written off related to sale of business unit	22,000,000
Indefinite-lived intangible assets, written off related to sale of business unit	$ 9,000,000
Mexico Corporate Trust
Dispositions
Dispositions, net of cash				$ 65,000,000
After-tax gain (loss) on sale				4,000,000
Goodwill written off related to sale of business unit				8,000,000
Indefinite-lived intangible assets, written off related to sale of business unit				$ 1,000,000
SourceNet
Dispositions
Dispositions, net of cash						$ 11,000,000
Pretax gain on sale						2,000,000
After-tax gain (loss) on sale						$ 10,000,000
Newton Private Clients
Dispositions
Dispositions, net of cash					$ 120,000,000
Pretax gain on sale					27,000,000
After-tax gain (loss) on sale					5,000,000
Goodwill written off related to sale of business unit					69,000,000
Indefinite-lived intangible assets, written off related to sale of business unit					$ 7,000,000
Cutwater Asset Management
Acquisitions
Business acquisition, assets under management acquired		$ 23,000,000,000
HedgeMark International, LLC
Acquisitions
Ownership percentage acquired (percent)			65.00%
Payments to acquire business			$ 26,000,000
Ownership percentage prior to acquisition (percent)			35.00%
Goodwill			$ 47,000,000
Intangible assets			$ 1,000,000