Financing Receivable, Modified, Weighted Average Term Extension and Interest Only Payments

No definition available.

Name:	htlf_FinancingReceivableModifiedWeightedAverageTermExtensionAndInterestOnlyPayments
Namespace Prefix:	htlf_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Financing Receivable, Modified, Weighted Average Term Extension and Interest Rate Reduction

+ References

No definition available.

+ Details

Name:	htlf_FinancingReceivableModifiedWeightedAverageTermExtensionAndInterestRateReduction
Namespace Prefix:	htlf_
Data Type:	xbrli:durationItemType
Balance Type:	na
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

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-34

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-33

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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

- Definition

Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

+ Details

Name:	us-gaap_FinancingReceivableModifiedWeightedAverageTermIncreaseFromModification
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
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_LoanRestructuringModificationAxis=us-gaap_ExtendedMaturityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=htlf_ExtendedMaturityAndInterestOnlyPaymentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=us-gaap_ExtendedMaturityAndInterestRateReductionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=htlf_AgriculturalAndAgriculturalRealEstatePortfolioMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

LOANS (Financial effect of loan modifications) (Details)	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Commercial and industrial \| Commercial and industrial \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension (Months)	8 months	8 months
Commercial and industrial \| Commercial and industrial \| Term Extension and Interest Only Payments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Only Payments (Months)	0 months	0 months
Commercial and industrial \| Commercial and industrial \| Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Rate Reduction (Months)	0 months	0 months
Commercial and industrial \| Non-owner occupied commercial real estate \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension (Months)	13 months
Commercial and industrial \| Non-owner occupied commercial real estate \| Term Extension and Interest Only Payments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Only Payments (Months)	0 months
Commercial and industrial \| Non-owner occupied commercial real estate \| Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Rate Reduction (Months)	25 months
Commercial and industrial \| Real Estate Construction \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension (Months)	13 months	6 months
Commercial and industrial \| Real Estate Construction \| Term Extension and Interest Only Payments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Only Payments (Months)	0 months	0 months
Commercial and industrial \| Real Estate Construction \| Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Rate Reduction (Months)	0 months	0 months
Commercial and industrial \| Owner occupied commercial real estate \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension (Months)		0 months
Commercial and industrial \| Owner occupied commercial real estate \| Term Extension and Interest Only Payments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Only Payments (Months)		12 months
Commercial and industrial \| Owner occupied commercial real estate \| Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Rate Reduction (Months)		0 months
Residential real estate \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension (Months)	4 months	12 months
Residential real estate \| Term Extension and Interest Only Payments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Only Payments (Months)	0 months	0 months
Residential real estate \| Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Rate Reduction (Months)	0 months	0 months
Consumer \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension (Months)	83 months
Consumer \| Term Extension and Interest Only Payments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Only Payments (Months)	0 months
Consumer \| Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Rate Reduction (Months)	0 months
Agricultural and agricultural real estate \| Real Estate Construction \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension (Months)		11 months
Agricultural and agricultural real estate \| Real Estate Construction \| Term Extension and Interest Only Payments
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Only Payments (Months)		0 months
Agricultural and agricultural real estate \| Real Estate Construction \| Term Extension and Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted Average Term Extension and Interest Rate Reduction (Months)		0 months