Employee Benefit Plans (Details) (USD $)
|
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2014
|
Dec. 31, 2013
|
Dec. 31, 2012
|
|
Employees' Stock Ownership Plan | |||
Number of allocated shares acquired prior to December 31, 1992 | 479,755buse_GrandfatheredESOPNumberOfAllocatedShares | 543,471buse_GrandfatheredESOPNumberOfAllocatedShares | |
Associated fair values of allocated shares acquired prior to December 31, 1992 | $ 3,100,000buse_GrandfatheredESOPFairValueOfAllocatedShares | $ 3,200,000buse_GrandfatheredESOPFairValueOfAllocatedShares | |
Shares | |||
Allocated shares | 171,988us-gaap_EmployeeStockOwnershipPlanESOPNumberOfAllocatedShares | 192,171us-gaap_EmployeeStockOwnershipPlanESOPNumberOfAllocatedShares | |
Fair Value | |||
Allocated shares, Fair Value | 1,100,000buse_EmployeeStockOwnershipPlanESOPAllocatedSharesFairValue | 1,100,000buse_EmployeeStockOwnershipPlanESOPAllocatedSharesFairValue | |
Profit Sharing Plan | |||
Vesting period | 5 years | ||
Expenses related to employee benefit plans | |||
Employee benefits | 2,636,000buse_EmployeeBenefitExpense | 2,975,000buse_EmployeeBenefitExpense | 3,024,000buse_EmployeeBenefitExpense |
Interest on employee stock ownership plan debt | 5,000us-gaap_EmployeeStockOwnershipPlanESOPInterestPaymentsFromESOP | ||
Total employer contributions | 2,636,000us-gaap_DefinedContributionPlanCostRecognized | 2,975,000us-gaap_DefinedContributionPlanCostRecognized | 3,029,000us-gaap_DefinedContributionPlanCostRecognized |
Deferred compensation plans for deferral of performance bonuses | |||
Deferred compensation expense | 300,000us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense | 200,000us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense | 200,000us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense |
Deferred compensation liability | $ 5,100,000us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability | $ 4,800,000us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability | $ 4,500,000us-gaap_DeferredCompensationArrangementWithIndividualRecordedLiability |
X | ||||||||||
- Details
|
X | ||||||||||
- Definition
Represents the period during which the rights of the participants vest under the defined contribution plans. No definition available.
|
X | ||||||||||
- Definition
Represents the amount of expenditure related to employee benefits incurred during the period. No definition available.
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Definition
Represents the fair value of shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. No definition available.
|
X | ||||||||||
- Details
|
X | ||||||||||
- Definition
For grandfathered ESOP shares acquired prior to January 1, 1993, the fair value of shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. No definition available.
|
X | ||||||||||
- Definition
For grandfathered ESOP shares acquired prior to January 1, 1993, the number of shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. No definition available.
|
X | ||||||||||
- Details
|
X | ||||||||||
- Definition
The compensation expense recognized during the period pertaining to the deferred compensation arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Definition
The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Definition
The amount of the cost recognized during the period for defined contribution plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Definition
An entity often discloses the amount of interest paid by the ESOP to a lender. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Definition
The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Details
|