Restrictions On Cash Due From Banks	12 Months Ended
Dec. 31, 2020
Restricted Cash and Investments [Abstract]
Restrictions On Cash Due From Banks	RESTRICTIONS ON CASH AND DUE FROM BANKS City National was previously required to maintain an average reserve balance with the Federal Reserve Bank of Richmond to compensate for services provided by the Federal Reserve and to meet statutory required reserves for demand deposits. The average amount of the reserve balance for the year ended December 31, 2019 was approximately $47.3 million. On March 15, 2020, the Board of Governors of the Federal Reserve waived the average reserve balance requirement effective March 26, 2020.

The entire disclosure for cash and cash equivalent footnotes, which may include the types of deposits and money market instruments, applicable carrying amounts, restricted amounts and compensating balance arrangements. Cash and equivalents include: (1) currency on hand (2) demand deposits with banks or financial institutions (3) other kinds of accounts that have the general characteristics of demand deposits (4) short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments maturing within three months from the date of acquisition qualify.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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