Interest-Bearing Deposits - Summary of Interest-Bearing Deposits (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Banking And Thrift [Abstract]
Demand	$ 183,680	$ 183,759
Statement and Passbook Savings	435,377	384,330
$250 and over	8,206	13,640
Certificates of Deposit: Other	192,455	168,723
Individual Retirement Accounts	23,241	25,063
Total	$ 842,959	$ 775,515

Other Time Deposits

No definition available.

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- Definition

Time Deposit Individual Retirement Accounts

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

The amount of money in accounts that may bear interest and that the depositor is entitled to withdraw at any time without prior notice.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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+ Details

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- Definition

The aggregate of all domestic and foreign interest-bearing deposit liabilities.

+ References

+ Details

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=50488274&loc=d3e64164-112818

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