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Amount of stock options issued or issuable in consideration for the business combination.

No definition available.

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The cash outflow per share associated with the acquisition of business during the period. The cash portion only of the acquisition price.

No definition available.

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Ratio applied to the conversion of options to purchase common stock.

No definition available.

Name:	buse_BusinessCombinationOptionsToPurchaseCommonStockConversionRatio
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Contractual amount of credit impaired loans at the acquisition date.

No definition available.

Name:	buse_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContractualAmountOfCreditImpairedLoans
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Amount of fair value of credit impaired loans acquired at the acquisition date.

No definition available.

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The amount of fair value of deposits assumed (as defined) at the acquisition date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Amount of loans acquired at the acquisition date.

No definition available.

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Amount of loans held for sale acquired at the acquisition date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Amount of other assets acquired at the acquisition date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The amount of other borrowings recognized as of the acquisition date

No definition available.

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Data Type:	xbrli:monetaryItemType
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Amount of other liabilities assumed at the acquisition date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The amount of other real estate owned properties (OREO) recognized as of the acquisition date

No definition available.

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Amount of fair value of performing loans including loans held for sale acquired at the acquisition date.

No definition available.

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Amount of investments in debt and equity securities, available-for-sale, acquired at the acquisition date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Ratio applied to the conversion of stock received or as a right to receive as consideration.

No definition available.

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Amount outstanding of credit impaired loans at the balance sheet date.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The estimated remaining life for loans expected to be accreted, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Amount of gross, fair value of performing loans including loans held for sale acquired at the acquisition date.

No definition available.

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Represents the number of banking centers.

No definition available.

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Period Type:	instant

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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Number of shares of equity interests issued or issuable to acquire entity.

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

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.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

No definition available.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- References

No definition available.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of assets acquired at the acquisition date.

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- References

No definition available.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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- References

No definition available.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=84160947&loc=d3e2207-128464

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The amount of property, plant, and equipment recognized as of the acquisition date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 2
-Subparagraph (a)(2)
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The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

No definition available.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
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-Name Accounting Standards Codification
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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
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