Financing Receivable, Loan Portfolio, COVID-19, Deferral Period

No definition available.

Name:	lkfn_FinancingReceivableLoanPortfolioCOVID19DeferralPeriod
Namespace Prefix:	lkfn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Financing Receivable, Loan Portfolio, Deferrals, COVID-19, Number of Borrowers

+ References

No definition available.

+ Details

Name:	lkfn_FinancingReceivableLoanPortfolioDeferralsCOVID19NumberOfBorrowers
Namespace Prefix:	lkfn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Financing Receivable, Loan Portfolio, Deferrals, COVID-19

+ References

No definition available.

+ Details

Name:	lkfn_FinancingReceivableLoanPortfolioDeferralsCovid19
Namespace Prefix:	lkfn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of loans under first deferral action, pursuant to COVID 19 deferrals.

+ References

No definition available.

+ Details

Name:	lkfn_FinancingReceivableLoanPortfolioDeferralsCovid19LoansUnderFirstDeferralAction
Namespace Prefix:	lkfn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of loans under fourth deferral action, pursuant to COVID 19 deferrals.

+ References

No definition available.

+ Details

Name:	lkfn_FinancingReceivableLoanPortfolioDeferralsCovid19LoansUnderFourthDeferralAction
Namespace Prefix:	lkfn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Financing Receivable Loan Portfolio Deferrals Covid19 Loans Under Fourth Deferral Action, Percentage

+ References

No definition available.

+ Details

Name:	lkfn_FinancingReceivableLoanPortfolioDeferralsCovid19LoansUnderFourthDeferralActionPercentage
Namespace Prefix:	lkfn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of loans under second deferral action, pursuant to COVID 19 deferrals.

+ References

No definition available.

+ Details

Name:	lkfn_FinancingReceivableLoanPortfolioDeferralsCovid19LoansUnderSecondDeferralAction
Namespace Prefix:	lkfn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of loans under third deferral action, pursuant to COVID 19 deferrals.

+ References

No definition available.

+ Details

Name:	lkfn_FinancingReceivableLoanPortfolioDeferralsCovid19LoansUnderThirdDeferralAction
Namespace Prefix:	lkfn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Financing Receivable, Loan Portfolio, Deferrals, COVID-19, Percentage of Loan Portfolio

+ References

No definition available.

+ Details

Name:	lkfn_FinancingReceivableLoanPortfolioDeferralsCovid19PercentageOfLoanPortfolio
Namespace Prefix:	lkfn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Increase (decrease) in allowance for loan loss.

+ References

No definition available.

+ Details

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

- Definition

The minimum loan amount required for credit quality analysis.

+ References

No definition available.

+ Details

Name:	lkfn_LoanAmountOfCreditQualityAnalysis
Namespace Prefix:	lkfn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

+ Details

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

- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 80
-URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922355-210448

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (1)

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1404
-Paragraph (a)

+ Details

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

- Details

Name:	us-gaap_CollateralAxis=us-gaap_CommercialRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConsumerLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=lkfn_PayCheckProtectionProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_PassMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=lkfn_CommercialRealEstateNonownerOccupiedLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) loan borrower	Dec. 31, 2020 USD ($) borrower	Dec. 31, 2019 USD ($) loan
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan amount of credit quality analysis	$ 250,000
Loans receivable before allowance for credit loss	4,287,841,000
Loans modified In troubled debt restructured loans	2,200,000
Increase in allowance for loan loss	$ (423,000)		$ (484,000)
Number of loans modified \| loan	8		1
Financing receivable, loan portfolio, deferrals, COVID-19	$ 11,000	$ 100,700,000
Financing receivable, loan portfolio, deferrals, COVID-19, borrowers \| borrower		49
Financing receivable, loan portfolio, deferrals, COVID-19, percentage of loan portfolio (as a percent)		2.20%
Financing Receivable, Loan Portfolio, Deferrals, COVID-19, Period		90 days
Construction and land development loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans modified In troubled debt restructured loans			$ 2,400,000
Number of loans modified \| loan			5
Total commercial loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, loan portfolio, deferrals, COVID-19		$ 98,200,000
Financing receivable, loan portfolio, deferrals, COVID-19, borrowers \| borrower		22
Financing receivable, loan portfolio, deferrals, COVID-19, percentage of loan portfolio (as a percent)		2.30%
Loans under second deferral action		$ 22,800,000
Loans under third deferral action		41,900,000
Loans under fourth deferral action		24,100,000
Loans under first deferral action		11,900,000
Total consumer loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans modified In troubled debt restructured loans	$ 5,800,000	5,500,000
Financing receivable, loan portfolio, deferrals, COVID-19		$ 2,500,000
Financing receivable, loan portfolio, deferrals, COVID-19, borrowers \| borrower	1	27
Financing receivable, loan portfolio, deferrals, COVID-19, percentage of loan portfolio (as a percent)		0.70%
PPP \| Pass
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans receivable before allowance for credit loss	$ 26,200,000
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, loan portfolio, deferrals, COVID-19, borrowers \| borrower		2
Financing Receivable Loan Portfolio Deferrals Covid19 Loans Under Fourth Deferral Action, Percentage		90.00%
Commercial Real Estate and Multi-family Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans modified In troubled debt restructured loans			$ 1,900,000
Number of loans modified \| loan			3