No definition available.

Name:	fkys_DEPOSITSLineItems
Namespace Prefix:	fkys_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents information pertaining to increase in highly rate sensitive deposits.

+ References

No definition available.

+ Details

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Namespace Prefix:	fkys_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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
-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=120398452&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The net cash inflow or outflow for the increase (decrease) in the beginning and end of period deposits balances.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3095-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 230
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121551529&loc=d3e60009-112784

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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DEPOSITS - Additional Information (Details) - USD ($)	9 Months Ended
DEPOSITS - Additional Information (Details) - USD ($)	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
DEPOSITS [Line Items]
Increase (Decrease) in Deposits	$ 157,591,000	$ 69,425,000
Deposits.	919,219,000		$ 761,628,000
Increase in highly rate sensitive deposits	58,000,000
Stimulus Funds
DEPOSITS [Line Items]
Increase (Decrease) in Deposits	19,000,000
Paycheck Protection Program Loans
DEPOSITS [Line Items]
Increase (Decrease) in Deposits	$ 31,729,000