Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Required, Collateral, Amount of FHLB Stock

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Number of Wholly-owned Trust Subsidiaries that Issue Preferred Securities

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Subordinated Notes Qualified as Tier Two Capital

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Face (par) amount of the original debt instrument that was repurchased.

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Amount, after accumulated amortization, of debt discount.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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Fixed interest rate related to the interest rate derivative.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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OTHER BORROWINGS (Narrative) (Details)		12 Months Ended
OTHER BORROWINGS (Narrative) (Details)	May 10, 2016 USD ($)	Dec. 31, 2020 USD ($) subsidiary	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	May 18, 2018 USD ($)	Dec. 15, 2015 USD ($)	Dec. 17, 2014 USD ($)
Debt Instrument [Line Items]
Long-term debt		$ 457,042,000	$ 275,773,000
FHLB stock, required collateral		13,600,000	11,300,000
Additional collateral, aggregate fair value		4,960,000,000	4,110,000,000
FHLB borrowing capacity		$ 1,560,000,000
Number of wholly-owned trust subsidiaries that issue preferred securities \| subsidiary		15
Interest Rate Swap
Debt Instrument [Line Items]
Amount of hedged debt	$ 40,000,000.0
Interest Rate Swap \| Cash Flow Hedging
Debt Instrument [Line Items]
Amount of hedged debt		$ 105,000,000.0			$ 9,000,000.0
Nonrevolving Credit Facility
Debt Instrument [Line Items]
Borrowing capacity		55,000,000.0				$ 55,000,000.0
Available borrowings		6,500,000
Line of credit outstanding		0
Nonrevolving Credit Facility \| Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging
Debt Instrument [Line Items]
Amount of hedged debt	$ 40,000,000.0	44,400,000	51,400,000
Fixed interest rate on derivative (as a percent)	2.50%
Term of derivative instrument	5 years
Tier 1
Debt Instrument [Line Items]
Subordinated notes qualified as Tier 2 capital		44,700,000
Paycheck Protection Program Liquidity Fund
Debt Instrument [Line Items]
Long-term debt		188,872,000	0
Remaining borrowing capacity		788,200,000
Trust preferred securities
Debt Instrument [Line Items]
Long-term debt		146,323,000	145,343,000
Deferred issuance costs		74,000
Trust preferred securities \| Tier 1
Debt Instrument [Line Items]
Long-term debt		146,300,000	145,200,000
Trust preferred securities \| Heartland Financial Statutory Trust IV
Debt Instrument [Line Items]
Repurchased debt amount				$ 2,600,000
Contracts payable for purchase of real estate and other assets
Debt Instrument [Line Items]
Long-term debt		1,983,000	1,892,000
Debt issued							$ 75,000,000.0
Debt discount							$ 1,100,000
Stated interest rate (as a percent)							5.75%
Contracts payable for purchase of real estate and other assets \| Other Assets
Debt Instrument [Line Items]
Unamortized debt issuance expense		$ 151,000	$ 189,000