Accumulated other comprehensive income gain loss on fair value hedges.

No definition available.

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- Definition

Interest rate fair value hedge gain (loss) reclassified from accumulated accumulated other comprehensive income into interest income during period.

+ References

No definition available.

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

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- 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.

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

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- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

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- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

The number of derivative instruments of a particular group held by the entity.

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

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-Topic 815
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- Definition

Maximum period of hedging exposure to variability in future cash flows for forecasted transaction of interest rate cash flow hedge, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes forecasted transaction for payment of variable interest on existing financial instrument.

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

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Derivatives and Hedging Activities - Additional Information (Detail) bbl in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025 USD ($) Derivative	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) Derivative bbl	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) Derivative	Jan. 31, 2025 USD ($) Derivative
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Termination value of derivatives in net liability position	$ 4,400,000		$ 4,400,000
Collateral posted for derivative instruments	$ 4,400,000		$ 4,400,000
Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest rate hedging exposure to variability in future cash flows for forecasted transactions, maximum period			11 years
Interest Rate Swap [Member] \| Derivatives Designated as Hedging Instruments [Member] \| Fair Value Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Unrealized gain on terminated fair value hedges in AOCI			$ 47,600,000		$ 50,400,000
Number of interest rate swaps \| Derivative	0		0		0
Interest Rate Swap [Member] \| Derivatives Designated as Hedging Instruments [Member] \| Fair Value Hedging [Member] \| Increase To Interest Income [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair value hedges reclassification from AOCI to interest	$ 1,300,000	$ 1,200,000	$ 3,700,000	$ 4,900,000
Interest Rate Swap [Member] \| Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	$ 51,500,000		$ 51,500,000		$ 51,500,000
Number of interest rate swaps \| Derivative	2		2		2
Reclassification from AOCI to interest	$ 600,000		$ 600,000
Interest Rate Swap [Member] \| Derivatives not Designated as Hedging Instruments [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	$ 11,600,000,000		$ 11,600,000,000		$ 5,500,000,000
Number of interest rate swaps \| Derivative	834		834		298
Interest Rate Swap [Member] \| Derivatives not Designated as Hedging Instruments [Member] \| Heartland Financial USA, Inc [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount						$ 4,200,000,000
Number of interest rate swaps \| Derivative						478
Interest Rate Floor [Member] \| Derivatives Designated as Hedging Instruments [Member] \| Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	$ 3,000,000,000		$ 3,000,000,000		$ 3,000,000,000
Reclassification from AOCI to interest	$ 1,800,000		$ 1,800,000
Commodity Derivatives [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative number of commodity swaps and option contracts \| Derivative	14		14
Commodity Derivatives [Member] \| Derivatives not Designated as Hedging Instruments [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate remaining volume \| bbl			2.1