DEPOSITS (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
DEPOSITS
Non-interest bearing demand	$ 203,583,000	$ 198,569,000
Interest bearing demand	278,869,000	275,472,000
Savings	195,310,000	212,280,000
Time certificates of deposits less than $250,000	327,236,000	259,841,000
Time certificates of deposits $250,000 or greater	39,782,000	33,185,000
Other time	1,100,000	1,092,000
Total deposits	$ 1,045,880,000	$ 980,439,000

The aggregate amount of other time deposit liabilities.

No definition available.

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- Definition

The aggregate amount of domestic and foreign time deposit liabilities (including certificates of deposits, individual retirement accounts and open accounts) in denominations of $250,000 or more.

+ References

No definition available.

+ Details

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- Definition

The aggregate amount of domestic or foreign time deposits (including certificates of deposits, individual retirement accounts and open accounts) that total to less than $250,000.

+ References

No definition available.

+ Details

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Namespace Prefix:	fkys_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

+ Details

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- References

No definition available.

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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

Amount of money in interest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

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+ Details

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- Definition

Amount of money in noninterest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

+ References

+ Details

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