Name:	buse_FederalFundsMaturityPeriod
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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the maximum maturity period of short-term debt.

No definition available.

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Weighted average interest rate of debt outstanding.

No definition available.

Name:	us-gaap_DebtWeightedAverageInterestRate
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Name:	us-gaap_FederalFundsPurchased
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Balance Type:	credit
Period Type:	instant

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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.

No definition available.