Variable Interest Entities (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Variable Interest Entities
Affordable housing investments	$ 222,877	$ 186,423
Affordable Housing VIEs - not primary beneficiary
Variable Interest Entities
Affordable housing investments	222,900	186,400
Unfunded commitments for affordable housing investments	93,800
Aggregate carrying value of private equity and alternative investment funds	$ 24,100	$ 29,200

Investments in entities formed to provide affordable housing.

No definition available.

Name:	cyn_AffordableHousingInvestments
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- Definition

The part of investor's commitment in affordable housing investments not yet drawn or utilized.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph a

-URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5728-111685

+ Details

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