Reserves on Deposit with the Federal Reserve Bank and Federal Bank Stock Shares Held at Federal Reserve Bank and Federal Home Loan Bank (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Disclosure Shares Held At Federal Reserve Bank And Federal Home Loan Bank [Abstract]
FHLB stock holdings	$ 18,900	$ 17,250
FRB stock holdings	$ 41,120	$ 40,342

Disclosure - Shares Held at Federal Reserve Bank and Federal Home Loan Bank [Abstract]

No definition available.

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

+ Details

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- Definition

Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

+ Details

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