Represents the information pertaining to the variance in amount.

No definition available.

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Namespace Prefix:	lkfn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Assets Pledged As Collateral For Loans Receivable [Line Items]

+ References

No definition available.

+ Details

Name:	lkfn_AssetsPledgedAsCollateralForLoansReceivableLineItems
Namespace Prefix:	lkfn_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represent the discount percentage used for evaluating collateral pledged for financing transactions.

+ References

No definition available.

+ Details

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Namespace Prefix:	lkfn_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the information pertaining to the variance in percentage.

+ References

No definition available.

+ Details

Name:	lkfn_PercentageOfVariance
Namespace Prefix:	lkfn_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Qualitative Information, Prepayment Speed

+ References

No definition available.

+ Details

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Namespace Prefix:	lkfn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average maturity of residential mortgages receivable, in 'PnYnMnDnTnHnMnS' format.

+ References

No definition available.

+ Details

Name:	lkfn_WeightedAverageMaturityOfResidentialMortgages
Namespace Prefix:	lkfn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
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-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-2

+ Details

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

- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-2

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PledgedStatusAxis=lkfn_CommercialRealEstatesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PledgedStatusAxis=lkfn_InventoryFinishedGoodsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PledgedStatusAxis=lkfn_FinishedGoodsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PledgedStatusAxis=lkfn_InventoryWorkInProcessMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_PledgedStatusAxis=us-gaap_EquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_PledgedStatusAxis=lkfn_MarketableSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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- Details

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FAIR VALUE DISCLOSURES - Additional Information (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2023 USD ($) prepaymentSpeed	Dec. 31, 2022 prepaymentSpeed
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	3.50%
Mortgage servicing rights	$ 2,300,000
Weighted average maturity of residential mortgages	20 years
Qualitative information used to estimate fair value \| prepaymentSpeed	148	159
Discount rate used to estimate fair value		9.50%
Minimum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Amount of variance	$ 100,000
Discount rate used to estimate fair value	9.50%
Minimum \| Commercial Real Estates \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	30.00%
Minimum \| Inventory Finished Goods \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	40.00%
Minimum \| Finished Goods \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	40.00%
Minimum \| Inventory Work In Process \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	60.00%
Minimum \| Equipment \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	20.00%
Minimum \| Marketable Securities \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	10.00%
Maximum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Discount rate used to estimate fair value	11.50%
Maximum \| Commercial Real Estates \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	50.00%
Maximum \| Inventory Finished Goods \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	60.00%
Maximum \| Finished Goods \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	60.00%
Maximum \| Inventory Work In Process \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	100.00%
Maximum \| Equipment \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	50.00%
Maximum \| Marketable Securities \| Level 3
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of discount from appraised value (in hundredths)	30.00%
Municipal Notes \| Minimum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	(5.00%)
Municipal Notes \| Maximum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	5.00%
US Government Agencies Short-term Debt Securities \| Minimum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	(3.00%)
US Government Agencies Short-term Debt Securities \| Maximum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	3.00%
U.S. Treasury securities \| Minimum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	(1.00%)
U.S. Treasury securities \| Maximum
Assets Pledged As Collateral For Loans Receivable [Line Items]
Percentage of variance	1.00%