Label	Element	Value
Effect Of Adjustments Due To Accounting Standards Update	cyn_EffectOfAdjustmentsDueToAccountingStandardsUpdate	$ (11,941)
Retained Earnings [Member]
Effect Of Adjustments Due To Accounting Standards Update	cyn_EffectOfAdjustmentsDueToAccountingStandardsUpdate	$ (11,941)

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets as a result of a cumulative effect adjustment for reclassification adjustment made to prior period financial statement amounts.

No definition available.

Name:	cyn_EffectOfAdjustmentsDueToAccountingStandardsUpdate
Namespace Prefix:	cyn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration