First Busey (BUSE) 10-K 10 Mar 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Mar. 10, 2015	Jun. 30, 2014
Document and Entity Information
Entity Registrant Name	FIRST BUSEY CORP /NV/
Entity Central Index Key	314489
Document Type	10-K
Document Period End Date	31-Dec-14
Amendment Flag	FALSE
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$450.90
Entity Common Stock, Shares Outstanding		86,869,771
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
ASSETS
Cash and due from banks (interest-bearing 2014 $243,769; 2013 $118,228)	$339,438	$231,603
Securities available for sale, at fair value	759,065	841,310
Securities held to maturity, at amortized cost	2,373	834
Loans held for sale	10,400	13,840
Loans (net of allowance for loan losses 2014 $47,453; 2013 $47,567)	2,357,837	2,233,893
Premises and equipment	63,974	65,827
Goodwill	20,686	20,686
Other intangible assets	6,687	9,571
Cash surrender value of bank owned life insurance	41,470	40,674
Other real estate owned (OREO)	216	2,133
Deferred tax assets, net	22,173	35,642
Other assets	41,288	43,562
Total assets	3,665,607	3,539,575
Deposits:
Noninterest-bearing	666,607	547,531
Interest-bearing	2,234,241	2,321,607
Total deposits	2,900,848	2,869,138
Securities sold under agreements to repurchase	198,893	172,348
Long-term debt	50,000
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Other liabilities	27,227	27,725
Total liabilities	3,231,968	3,124,211
Commitments and contingencies (see Note 18 - Commitments, Contingencies and Credit Risk)
Stockholders' Equity
Series C Preferred stock, $.001 par value, 72,664 shares authorized, issued and outstanding, $1,000.00 liquidation value	72,664	72,664
Common stock, $.001 par value, authorized 200,000,000 shares; issued 88,287,132 shares	88	88
Surplus	593,687	593,144
Retained earnings (deficit)	-210,384	-225,722
Accumulated other comprehensive income	5,817	4,456
Total stockholders' equity before treasury stock	461,872	444,630
Common stock shares held in treasury at cost - 2014 1,426,323; 2013 1,482,777	-28,233	-29,266
Total stockholders' equity	433,639	415,364
Total liabilities and stockholders' equity	$3,665,607	$3,539,575

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
CONSOLIDATED BALANCE SHEETS
Cash and due from banks, interest-bearing (in dollars)	$243,769	$118,228
Loans, allowance for loan losses (in dollars)	$47,453	$47,567
Preferred stock, par value (in dollars per share)	$0.00	$0.00
Preferred stock, shares authorized	72,664	72,664
Preferred stock, shares issued	72,664	72,664
Preferred stock, shares outstanding	72,664	72,664
Preferred stock, liquidation value (in dollars per share)	$1,000	$1,000
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	88,287,132	88,287,132
Common stock shares held in treasury	1,426,323	1,482,777

CONSOLIDATED_STATEMENTS_OF_INC

CONSOLIDATED STATEMENTS OF INCOME (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Interest income:
Interest and fees on loans	$92,395	$92,233	$98,614
Interest and dividends on investment securities:
Taxable interest income	12,427	12,570	14,626
Non-taxable interest income	3,253	3,893	3,676
Total interest income	108,075	108,696	116,916
Interest expense:
Deposits	5,123	7,099	12,496
Federal funds purchased and securities sold under agreements to repurchase	186	186	279
Short-term borrowings		15	35
Long-term debt	7	125	648
Junior subordinated debt owed to unconsolidated trusts	1,183	1,206	1,312
Total interest expense	6,499	8,631	14,770
Net interest income	101,576	100,065	102,146
Provision for loan losses	2,000	7,500	16,500
Net interest income after provision for loan losses	99,576	92,565	85,646
Other income:
Trust fees	19,559	18,521	17,592
Commissions and brokers' fees, net	2,716	2,416	2,102
Remittance processing	9,421	8,354	8,426
Service charges on deposit accounts	12,038	11,947	11,646
Other service charges and fees	6,238	5,961	5,717
Gain on sales of loans	4,723	10,227	12,535
Security gains, net	776	553	1,597
Other	3,470	4,604	7,237
Total other income	58,941	62,583	66,852
Other expense:
Salaries and wages	51,734	52,891	53,668
Employee benefits	9,607	10,922	11,124
Net occupancy expense of premises	8,462	8,489	8,899
Furniture and equipment expenses	4,725	4,848	5,146
Data processing	10,879	10,465	11,061
Amortization of intangible assets	2,884	3,132	3,315
Regulatory expense	2,079	2,290	2,543
OREO expense	93	503	1,303
Other	17,746	18,771	22,585
Total other expense	108,209	112,311	119,644
Income before income taxes	50,308	42,837	32,854
Income taxes	17,534	14,111	10,497
Net income	32,774	28,726	22,357
Preferred stock dividends	727	3,633	3,633
Net income available for common stockholders	$32,047	$25,093	$18,724
Basic earnings per common share (in dollars per share)	$0.37	$0.29	$0.22
Diluted earnings per common share (in dollars per share)	$0.37	$0.29	$0.22

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$32,774	$28,726	$22,357
Unrealized net gains (losses) on securities:
Unrealized net holding gains (losses) arising during period	2,902	-14,892	2,307
Reclassification adjustment for (gains) included in net income	-776	-553	-1,597
Other comprehensive income (loss) , before tax	2,126	-15,445	710
Income tax expense (benefit) related to items of other comprehensive income	765	-6,359	292
Other comprehensive income (loss), net of tax	1,361	-9,086	418
Comprehensive income	$34,135	$19,640	$22,775

CONSOLIDATED_STATEMENTS_OF_STO

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $)	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings (Deficit)	Accumulated Other Comprehensive Income	Treasury Stock	Unearned ESOP Shares	Total
In Thousands, unless otherwise specified
Balance at Dec. 31, 2011	$72,664	$88	$594,009	($238,085)	$13,124	($32,116)	($417)	$409,267
Increase (decrease) in shareholders' equity
Net income				22,357				22,357
Other comprehensive income (loss)					418			418
Issuance of 37,836, 22,493 and 23,640 shares of treasury stock for employee stock purchase Plan for the years 2014,2013 and 2012, respectively			-302			411		109
Net issuance of 18,618, 111,012 and 6,804 treasury stock for restricted stock unit vesting and related tax benefit for the years 2014, 2013 and 2012, respectively			-131			118		-13
Cash dividends common stock at $0.19, $0.12 and $0.24 per share for the years 2014,2013 and 2012, respectively				-20,794				-20,794
Stock dividend equivalents restricted stock units at $0.19, $0.12 and $0.24 per share for the years 2014,2013 and 2012, respectively			166	-166
Employee stock ownership plan shares allocated			-322				417	95
Stock based employee compensation			991					991
Preferred stock dividends				-3,633				-3,633
Balance at Dec. 31, 2012	72,664	88	594,411	-240,321	13,542	-31,587		408,797
Increase (decrease) in shareholders' equity
Net income				28,726				28,726
Other comprehensive income (loss)					-9,086			-9,086
Issuance of 37,836, 22,493 and 23,640 shares of treasury stock for employee stock purchase Plan for the years 2014,2013 and 2012, respectively			-288			394		106
Net issuance of 18,618, 111,012 and 6,804 treasury stock for restricted stock unit vesting and related tax benefit for the years 2014, 2013 and 2012, respectively			-2,145			1,927		-218
Cash dividends common stock at $0.19, $0.12 and $0.24 per share for the years 2014,2013 and 2012, respectively				-10,407				-10,407
Stock dividend equivalents restricted stock units at $0.19, $0.12 and $0.24 per share for the years 2014,2013 and 2012, respectively			87	-87
Stock based employee compensation			1,079					1,079
Preferred stock dividends				-3,633				-3,633
Balance at Dec. 31, 2013	72,664	88	593,144	-225,722	4,456	-29,266		415,364
Increase (decrease) in shareholders' equity
Net income				32,774				32,774
Other comprehensive income (loss)					1,361			1,361
Issuance of 37,836, 22,493 and 23,640 shares of treasury stock for employee stock purchase Plan for the years 2014,2013 and 2012, respectively			-481			692		211
Net issuance of 18,618, 111,012 and 6,804 treasury stock for restricted stock unit vesting and related tax benefit for the years 2014, 2013 and 2012, respectively			-375			341		-34
Cash dividends common stock at $0.19, $0.12 and $0.24 per share for the years 2014,2013 and 2012, respectively				-16,497				-16,497
Stock dividend equivalents restricted stock units at $0.19, $0.12 and $0.24 per share for the years 2014,2013 and 2012, respectively			212	-212
Stock based employee compensation			1,187					1,187
Preferred stock dividends				-727				-727
Balance at Dec. 31, 2014	$72,664	$88	$593,687	($210,384)	$5,817	($28,233)		$433,639

CONSOLIDATED_STATEMENTS_OF_STO1

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY
Issuance of shares of treasury stock for employee stock purchase plan	37,836	22,493	23,640
Issuance of shares of treasury stock for restricted stock unit vesting and related tax benefit	18,618	111,012	6,804
Cash dividends, common stock (in dollars per share)	$0.19	$0.12	$0.24
Stock dividends, restricted stock units (in dollars per share)	$0.19	$0.12	$0.24

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows from Operating Activities
Net income	$32,774	$28,726	$22,357
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based and non-cash compensation	1,187	1,079	991
Depreciation and amortization	8,456	8,598	8,759
Premises and equipment impairment			1,421
Provision for loan losses	2,000	7,500	16,500
Fair value adjustment on employee stock ownership plan shares allocated			-322
Provision for deferred income taxes	12,715	10,110	8,571
Amortization of security premiums and discounts, net	7,305	8,744	9,730
Net security gains	-776	-553	-1,597
Gain on sales of loans, net	-4,723	-10,227	-12,535
Increase in cash surrender value of bank owned life Insurance	-796	-1,189	-1,603
Net gains on disposition of premises and equipment	-19	-533
Net gains on disposition of OREO properties	-162	-260	-274
Increase (decrease) in deferred compensation	363	-49	-70
Change in assets and liabilities:
Decrease in other assets	2,274	9,880	8,368
(Decrease) increase in other liabilities	-650	-63	992
Net cash provided by operating activities before activities for loans originated for sale	59,948	61,763	61,288
Loans originated for sale	-222,976	-450,226	-576,862
Proceeds from sales of loans	231,139	486,616	564,643
Net cash provided by operating activities	68,111	98,153	49,069
Cash Flows from Investing Activities
Purchases of securities classified available for sale	-182,123	-83,718	-454,538
Purchases of securities classified held to maturity	-1,026	-839
Proceeds from sales of securities classified available for sale	74,113	16,365	59,570
Proceeds from maturities of securities classified available for sale	185,329	203,908	217,797
Proceeds from maturities of securities classified held to maturity	10
Net increase in loans	-126,604	-258,366	-33,680
Purchases of premises and equipment	-3,778	-2,549	-8,611
Proceeds from disposition of premises and equipment	78	2,856	77
Proceeds from sale of OREO properties	2,739	3,645	14,950
Net cash used in investing activities	-51,262	-118,698	-204,435
Cash Flows from Financing Activities
Net decrease in certificates of deposit	-86,300	-108,828	-116,287
Net increase (decrease) in demand deposits, money market and savings accounts	118,010	-2,326	333,125
Net increase in federal funds purchased and securities sold under agreements to repurchase	26,545	33,324	11,157
Principal payments on long-term debt		-7,000	-12,000
Proceeds from long-term debt	50,000
Value of shares surrendered upon vesting of restricted stock units to cover tax obligations	-45	-237
Cash dividends paid	-17,224	-14,040	-24,427
Net cash provided by (used in) financing activities	90,986	-99,107	191,568
Net increase (decrease) in cash and due from banks	107,835	-119,652	36,202
Cash and due from banks, beginning	231,603	351,255	315,053
Cash and due from banks, ending	339,438	231,603	351,255
Cash Payments for:
Interest	6,665	9,086	15,523
Income taxes	6,395	4,749	1,045
Non-cash Investing and Financing Activities:
Other real estate acquired in settlement of loans	660	2,068	9,674
Employee stock ownership plan shares allocated			$417

Significant_Accounting_Policie

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Significant Accounting Policies
Significant Accounting Policies
	Note 1.  Significant Accounting Policies
	Description of business
	First Busey Corporation is a Nevada corporation and a financial holding company whose subsidiaries provide retail and commercial banking services, remittance processing, and offer a full range of financial products and services, including depository, lending, security brokerage services, investment management and fiduciary services, to individual, corporate, institutional and governmental customers through its locations in downstate Illinois, Indianapolis, Indiana and southwest Florida.  The Company and its subsidiaries are subject to competition from other financial institutions and non-financial institutions providing financial products and services.  The Company and its subsidiaries are also subject to the regulations of certain regulatory agencies and undergo periodic examinations by those regulatory agencies.
	The significant accounting and reporting policies for the Company and its subsidiaries follow:
	Basis of consolidation
	The Consolidated Financial Statements include the accounts of the Company and its subsidiaries: Busey Bank and its wholly-owned subsidiary FirsTech, Inc.; and Busey Wealth Management, Inc. and its wholly-owned subsidiaries Busey Trust Company and Busey Capital Management, Inc.  The Company and its subsidiaries maintain various LLCs that hold specific assets for risk mitigation purposes and are consolidated into these financial statements.  All significant intercompany balances and transactions have been eliminated in consolidation.
	The Consolidated Financial Statements also exclude the following wholly-owned variable interest entities:  First Busey Statutory Trust II, First Busey Statutory Trust III and First Busey Statutory Trust IV because the Company is not the primary beneficiary.
	The Consolidated Financial Statements of the Company have been prepared in conformity with accounting principles generally accepted in the United States of America and conform to predominant practice within the banking industry.
	Use of estimates
	In preparing the accompanying Consolidated Financial Statements, the Company’s management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses for the reporting period.  Actual results could differ from those estimates.  Material estimates which are particularly susceptible to significant change in the near-term relate to the fair value of investment securities, the determination of the allowance for loan losses and the ability to realize its deferred tax assets.
	Comprehensive income
	Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income.  Although certain changes in assets and liabilities, such as unrealized gains and losses on available for sale securities, are reported as a separate component of the equity section of the balance sheet, such items, along with net income, are components of comprehensive income.
	Trust assets
	Assets held for customers in a fiduciary or agency capacity, other than trust cash on deposit at the Company’s bank subsidiary, are not assets of the Company and, accordingly, are not included in the accompanying Consolidated Financial Statements.  Busey Trust Company had assets under care of $5.2 billion and $5.0 billion at December 31, 2014 and 2013, respectively.
	Cash flows
	For purposes of the consolidated statement of cash flows, cash and due from banks includes cash on hand and amounts due from banks.  Cash flows from federal funds purchased and sold, short-term borrowings, and securities sold under agreements to repurchase are reported net, since their original maturities are less than three months.  Cash flows from loans and deposits are also reported net.
	Securities
	Securities classified as held to maturity are those debt securities that the Company intends to hold to maturity.  Securities held to maturity are carried at cost, adjusted for amortization of premiums and accretion of discounts.
	Securities classified as available for sale are those debt securities that the Company intends to hold for an indefinite period of time, but not necessarily to maturity, and marketable equity securities.  Any decision to sell a security classified as available for sale would be based on various factors, including significant movements in interest rates, changes in the maturity mix of the Company’s assets and liabilities, liquidity needs, regulatory capital considerations and other similar factors.  Securities available for sale are carried at fair value, with temporary unrealized gains and losses excluded from earnings and reported in other comprehensive income.
	Declines in the fair value of debt securities below their amortized cost are evaluated to determine whether the loss is temporary or other-than-temporary.  If the Company (a) has the intent to sell a debt security or (b) more likely than not will be required to sell the debt security before its anticipated recovery, then the Company recognizes the entire unrealized loss in earnings as an other-than-temporary loss.  If neither of these conditions are met, the Company evaluates whether a credit loss exists.  The impairment is separated into (x) the amount of the total impairment related to the credit loss and (y) the amount of total impairment related to all other factors.  The amount of the total other-than-temporary impairment related to the credit loss is recognized in earnings and the amount related to all other factors is recognized in other comprehensive income.
	The Company also evaluates whether the decline in fair value of an equity security is temporary or other-than-temporary.  In determining whether an unrealized loss on an equity security is temporary or other-than-temporary, management considers various factors, including the magnitude and duration of the impairment, the financial condition and near-term prospects of the issuer, and the intent and ability of the Company to hold the equity security to forecasted recovery.
	Purchase premiums and discounts are recognized in interest income using the interest method over the terms of the securities.  Gains and losses on the sale of securities are recorded on the trade date and are determined using the specific identification method.
	Loans held for sale
	Loans held for sale are those loans the Company has the intent to sell in the foreseeable future.  They consist of mortgage loans conforming to established guidelines and held for sale to investors and the secondary mortgage market.  Loans held for sale are carried at the lower of aggregate cost or estimated fair value, as determined by aggregate outstanding commitments from investors or current investor yield requirements.  Net unrealized losses, if any, are recognized through a valuation allowance by charges to income.  Gains and losses on sales of loans are recognized at settlement dates and are determined by the difference between the sales proceeds and the carrying amount of the loans after allocating cost to servicing rights retained.
	The Company enters into commitments to originate loans whereby the interest rate on the loan is determined prior to funding (rate lock commitments).  Rate lock commitments on mortgage loans that are intended to be sold are considered to be derivatives.  To avoid interest rate risk, the Company also enters into mortgage loan sales commitments at the time it makes the interest rate lock commitment.  Accordingly, such commitments along with any related fees received from potential borrowers are recorded at fair value, with changes in fair value recorded in the net gain or loss on sale of mortgage loans.  Fair value is based on the change in estimated fair value of the underlying mortgage loan.  The fair value is subject to change primarily due to changes in interest rates and is considered immaterial to the Consolidated Financial Statements.
	Loan servicing
	Servicing assets are recognized as separate assets when rights are acquired or retained through the sale of mortgage loans.  Mortgage servicing rights are initially recorded at fair value.  Fair value is based on a valuation model that calculates the present value of estimated future net servicing income.  Capitalized servicing rights are reported in other assets and are amortized into other income in proportion to, and over the period of, the estimated future net servicing income of the underlying financial assets.
	Mortgage servicing rights are periodically evaluated for impairment based on the fair value of those rights as compared to book value.  Fair values are estimated using discounted cash flows based on current expected future prepayment rates.  For purposes of measuring impairment, the rights must be stratified by one or more predominant risk characteristics of the underlying loans.  The Company stratifies its capitalized mortgage servicing rights based on the type of the underlying loans.  The amount of impairment recognized is the amount, if any, by which the amortized cost of the rights for each stratum exceeds its fair value.  If the Company later determines that all or a portion of the impairment no longer exists for a particular group of loans, a reduction of the allowance may be recorded as an increase to income.
	Servicing fee income is recorded for fees earned for servicing loans.  The fees are based on a contractual percentage of the outstanding principal and are recorded as income when earned.  The amortization of mortgage servicing rights is netted against loan servicing fee income.
	Loans
	Loans receivable that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off are stated at the amount of outstanding unpaid principal, adjusted for chargeoffs, the allowance for loan losses, and any deferred origination fees or costs on loans.
	Retail loan origination fees, net of certain direct loan origination costs, are deferred and the net amount is amortized as an adjustment of the related loan’s yield.  The Company is generally amortizing these amounts over the contractual life.  However, for long-term, fixed-rate residential mortgages, the Company has anticipated prepayments and assumes an estimated economic life of five years or less. Material commercial loan origination fees are amortized over the life of the loan which is usually a term of three years or less.  Commitment fees and costs are generally based upon a percentage of a customer’s maximum line of credit or fees related to standby letters of credit and are recognized as collected.
	Interest is accrued daily on the outstanding balances.  Loans are placed on non-accrual status when, in management’s opinion, the borrower may be unable to meet payment obligations as they become due, as well as when required by regulatory provisions.  Loans may be placed on non-accrual status regardless of whether or not such loans are considered past due.  Past due status is based on the contractual terms of the loan.
	Interest accrued in the current year but not collected for loans that are placed on non-accrual status or charged-off is reversed against interest income.  Interest accrued during the prior year but not collected for loans that are placed on non-accrual status or charged-off is charged against the allowance for loan losses.  The interest on these loans is accounted for on the cash-basis or cost-recovery method, until qualifying for return to accrual status.  Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured.
	Allowance for loan losses
	The allowance for loan losses is established as losses are estimated to have occurred through a provision for loan losses charged to earnings.  Loan losses are charged against the allowance for loan losses when management believes the uncollectibility of the loan balance is confirmed.  Subsequent recoveries, if any, are credited to the allowance.
	The allowance for loan losses is evaluated on a regular basis by management and is based upon management’s periodic review of the collectibility of the loans in light of historical experience, the nature and volume of the loan portfolio, adverse situations that may affect the borrower’s ability to repay, estimated value of any underlying collateral and prevailing economic conditions.  This evaluation is inherently subjective as it requires estimates that are susceptible to significant revision as more information becomes available.
	In addition, regulatory agencies, as an integral part of their examination process, periodically review the allowance for loan losses, and may require the Company to make additions to the allowance based on their judgment about information available to them at the time of their examinations.
	The allowance consists of specific and general components.  The specific component considers loans that are classified as impaired.  For such loans that are classified as impaired, an allowance is established when the discounted cash flows (or collateral value or observable market price) of the impaired loan is lower than the carrying amount of that loan.  The general component covers non-classified loans and classified loans not considered impaired, and is based on historical loss experience adjusted for qualitative factors.  Other adjustments may be made to the allowance for pools of loans after an assessment of internal or external influences on credit quality that are not fully reflected in the historical loss experience.
	Premises and equipment
	Land is stated at cost less accumulated depreciation of depreciable land improvements.  Premises and equipment are stated at cost less accumulated depreciation.  Depreciation is computed principally by the straight-line method over the estimated useful lives of the assets.  The estimated useful lives for premises and equipment are:
	Asset Description	Estimated Useful Life
	Buildings and improvements	3 – 40 years
	Furniture and equipment	3 – 10 years
	Long-lived assets
	Long-lived assets, including premises and equipment and intangible assets, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable.  An impairment loss would be recognized when estimated undiscounted future cash flows from operations of the asset are less than the carrying value of the asset.  The cash flows used for this analysis are those directly associated with and that are expected to arise as a direct result of the use and eventual disposition of the asset.  An impairment loss would be measured by the amount by which the carrying value of the asset exceeds its fair value.
	Other real estate owned
	OREO represents properties acquired through foreclosure or other proceedings in settlement of loans.  OREO is held for sale and is recorded at the date of foreclosure at the fair value of the properties less estimated costs of disposal, which establishes a new cost basis.  Any adjustment to fair value at the time of transfer to OREO is charged to the allowance for loan losses.  Property is evaluated regularly to ensure the recorded amount is supported by its current fair value, and valuation allowances to reduce the carrying amount to fair value less estimated costs to dispose are recorded as necessary.  Revenue, expense, gains and losses from the operations of foreclosed assets are included in operations.
	Goodwill
	Goodwill represents the excess of the cost of a business acquired over the fair value of the new assets acquired.  Goodwill is not amortized, but is subject to at least annual impairment assessments.  The Company has established December 31 as the annual impairment assessment date.  Accounting standards allow for goodwill to be tested for impairment by first performing a qualitative assessment to determine whether it is more likely than not that the fair value of the reporting unit is less than its carrying value.  If the reporting unit does not pass the qualitative assessment, then the reporting unit’s carrying value is compared to its fair value. The Company estimates the fair value of its reporting units as of the measurement date utilizing valuation methodologies including the comparable transactions approach and the control premium approach.  Goodwill is considered impaired if the carrying value of the reporting unit exceeds its fair value. There was no impairment determined at December 31, 2014 and 2013.  It is possible the Company will evaluate its goodwill for impairment on a more frequent basis than annually.  Future evaluations may result in impairment.  See Note 7 — Goodwill and Other Intangible Assets for further discussion.
	Cash surrender value of bank-owned life insurance
	The Company has purchased life insurance policies on certain executives and senior officers.  Life insurance is recorded at its cash surrender value.
	ASC Topic 715, “Compensation—Retirement Benefits” requires an employer to recognize a liability for post-employment benefits promised to an employee based on an arrangement between an employer and an employee. In an endorsement split-dollar arrangement, the employer owns and controls the policy, and the employer and employee split the life insurance policy’s cash surrender value and/or death benefits. If the employer agrees to maintain a life insurance policy during the employee’s retirement, the present value of the cost of maintaining the insurance policy would be accrued over the employee’s active service period. Similarly, if the employer agrees to provide the employee with a death benefit, the present value of the death benefit would be accrued over the employee’s active service period.
	Transfers of financial assets
	Transfers of financial assets are accounted for as sales only when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when: (1) the assets have been isolated from the Company, (2) the transferee obtains the right to pledge or exchange the assets it received, and no condition both constrains the transferee from taking advantage of its right to pledge or exchange and provides more than a modest benefit to the transferor, and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity or the ability to unilaterally cause the holder to return specific assets.
	Income taxes
	The Company is subject to income taxes in the U.S. federal and various state jurisdictions.  The Company and its subsidiaries file consolidated federal and state income tax returns with each subsidiary computing its taxes on a separate entity basis.  Tax regulations within each jurisdiction are subject to the interpretation of the related tax laws and regulations and require significant judgment to apply.  With few exceptions, the Company is no longer subject to U.S. federal, state or local tax examinations by tax authorities for the years before 2010.  The provision for income taxes is based on income as reported in the Consolidated Financial Statements.
	The Company has maintained significant net deferred tax assets for deductible temporary differences, the largest of which relates to the State of Illinois net operating loss carryforward and the allowance for loan losses. For income tax return purposes, only actual charge-offs are deductible, not the provision for loan losses. Under generally accepted accounting principles, a valuation allowance is required to be recognized if it is more likely than not that the deferred tax assets will not be realized. The determination of the recoverability of the deferred tax assets is highly subjective and dependent upon judgment concerning management’s evaluation of both positive and negative evidence, the forecasts of future income, applicable tax planning strategies, and assessments of the current and future economic and business conditions. The Company considers both positive and negative evidence regarding the ultimate recoverability of its deferred tax assets. Positive evidence includes available tax planning strategies and the probability that taxable income will continue to be generated in future periods, as it was in periods since March 31, 2010, while negative evidence includes a cumulative loss in 2009 and 2008 and certain business and economic trends. The Company evaluated the recoverability of its net deferred tax assets and established a valuation allowance for certain state net operating loss and credit carryforwards that are not expected to be fully realized. Management believes that it is more likely than not that the other deferred tax assets included in the accompanying Consolidated Financial Statements will be fully realized. The Company determined that no valuation allowance was required for any other deferred tax assets as of December 31, 2014, although there is no guarantee that those assets will be recognizable in future periods.
	The Company must assess the likelihood that any deferred tax assets will be realized through the reduction of taxes in future periods and establish a valuation allowance for those assets for which recovery is not more likely than not. In making this assessment, the Company must make judgments and estimates regarding the ability to realize the asset through the future reversal of existing taxable temporary differences, future taxable income, and the possible application of future tax planning strategies.  The Company’s evaluation gave consideration to the fact that all net operating loss carrybacks have been utilized.  Therefore, utilization of net operating loss carryforwards are dependent on implementation of tax strategies and continued profitability.
	Positions taken in tax returns may be subject to challenge upon examination by the taxing authorities. Uncertain tax positions are initially recognized in the Financial Statements when it is more likely than not the position will be sustained upon examination by the tax authorities. Such tax positions are both initially and subsequently measured as the largest amount of tax benefit that has a greater than 50% likelihood of being realized upon settlement with the tax authority, assuming full knowledge of the position and all relevant facts.  When applicable, the Company recognizes interest accrued related to unrecognized tax benefits and penalties in operating expenses.  The Company had no accruals for payments of interest and penalties at December 31, 2014 and 2013.
	At December 31, 2014, the Company was under examination by the Illinois Department of Revenue for the Company’s 2011 and 2012 income tax filings.
	Reclassifications
	Reclassifications have been made to certain prior year account balances, with no effect on net income or stockholders’ equity, to be consistent with the classifications adopted as of and for the year ended December 31, 2014.
Stock-based employee compensation
During the second quarter of 2010, the Company adopted the First Busey Corporation 2010 Equity Incentive Plan (“2010 Equity Plan”), which was approved at the annual stockholders meeting on May 19, 2010. The Company will no longer make any additional grants under prior plans.
The Company’s equity incentive plans are designed to encourage ownership of its common stock by its employees and directors, to provide additional incentive for them to promote the success of the Company’s business, and to attract and retain talented personnel. All of the Company’s employees and directors and those of its subsidiaries are eligible to receive awards under the plans. See Note 16 — Stock Incentive Plans for further discussion.
The Company calculates the compensation cost of its non-vested stock awards (restricted stock units) based on the Company’s stock price on the grant date multiplied by the number of units granted. This cost is recorded over a specified requisite service period (i.e. vesting period) ranging from one to five years. As the units cliff vest and are subject only to a service condition, the cost is recorded using straight-line amortization. No compensation cost is recognized for unvested awards that are forfeited.
Segment disclosure
Operating segments are components of a business that (i) engage in business activities from which it may earn revenues and incur expenses; (ii) have operating results that are reviewed regularly by the entity’s chief operating decision maker to make decisions about resources to be allocated to the segments and assess their performance; and (iii) for which discrete financial information is available. The Company’s segments are its three primary operating subsidiaries Busey Bank, FirsTech and Busey Wealth Management.
Business Combinations
Business combinations are accounted for under ASC 805, Business Combinations, using the acquisition method of accounting. The acquisition method of accounting requires an acquirer to recognize the assets acquired and the liabilities assumed at the acquisition date measured at their fair values as of that date. To determine the fair values, the Company may rely on third party valuations, such as appraisals, or internal valuations based on discounted cash flow analyses or other valuation techniques. Under the acquisition method of accounting, the Company will identify the acquirer and the closing date and apply applicable recognition principles.
On January 8, 2015, First Busey completed its acquisition of Herget Financial, headquartered in Pekin, Illinois.  This acquisition is a subsequent event and financial results of Herget Financial are not recognized in this Form 10-K.
Acquisition related costs are costs the Company incurs to effect a business combination.  Those costs may include legal, accounting, valuation, other professional or consulting fees, system conversions and marketing costs. The Company will account for acquisition related costs as expenses in the periods in which the costs are incurred and the services are received.  Costs that the Company expects, but is not obligated to incur in the future, to effect its plan to exit an activity of an acquiree or to terminate the employment of an acquiree’s employees are not liabilities at the acquisition date. Instead, the Company will recognize these costs in its post-combination financial statements in accordance with other applicable accounting guidance.
During 2014, First Busey incurred $0.4 million of acquisition expenses related to the acquisition of Herget Financial, comprised primarily of legal, accounting, and system conversion costs.
Derivative Financial Instruments
The Company enters into derivative financial instruments as part of its foreign currency risk management strategies.  These derivative financial instruments consist of foreign currency forward contracts to accommodate the business needs of its customers.  The derivative instruments are recorded on the balance sheet, as either an asset or liability, at their fair value.  For derivative instruments not accounted for as hedges, changes in fair value are recognized in other income.
Earnings per share
Basic earnings per share are computed by dividing net income available to common stockholders for the period by the weighted average number of common shares outstanding.
Diluted earnings per common share is computed using the treasury stock method and reflects the potential dilution that could occur if the Company’s outstanding stock options were exercised and restricted stock units were vested.  Stock options and restricted stock units for which the exercise or the grant price exceeds the average market price over the period have an anti-dilutive effect and are excluded from the calculation.  At December 31, 2014, 457,630 outstanding options, 573,833 warrants, and 353,976 restricted stock units were anti-dilutive and excluded from the calculation of common stock equivalents.  At December 31, 2013, 643,879 outstanding options, 573,833 warrants, and 347,253 restricted stock units were anti-dilutive and excluded from the calculation of common stock equivalents.
The following reflects net income per share calculations for basic and diluted methods:
	For the Years Ended December 31,
	2014		2013		2012
	(in thousands, except per share data)
Net income available to common stockholders	$	32,047	$	25,093	$	18,724
Shares:
Weighted average common shares outstanding	86,906		86,765		86,643
Dilutive effect of outstanding options, warrants and restricted stock units as determined by the application of the treasury stock method	386		299		9
Weighted average common shares outstanding, as adjusted for diluted earnings per share calculation	87,292		87,064		86,652
Basic earnings per common share	$	0.37	$	0.29	$	0.22
Diluted earnings per common share	$	0.37	$	0.29	$	0.22
Subsequent events
The Company has evaluated subsequent events for potential recognition and/or disclosure through the date the Consolidated Financial Statements included in this Annual Report on Form 10-K were issued.  On January 8, 2015, First Busey completed its acquisition of Herget Financial, headquartered in Pekin, Illinois.  See Note 22 — Acquisitions for further discussion.  On February 3, 2015, First Busey’s board of directors approved a repurchase plan under which the Company is authorized to repurchase its common stock.  See Note 16 — Stock Incentive Plans for further discussion.  Other than the completion of the acquisition of Herget Financial and stock repurchase approval, there were no significant subsequent events for the year ended December 31, 2014 through the filing date of these Consolidated Financial Statements.
Impact of new financial accounting standards
ASU 2014-04, “Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) - Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure.” ASU 2014-04 clarifies when an in-substance repossession or foreclosure occurs and requires interim and annual disclosures.  The new authoritative guidance will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2014 and is not expected to have a significant impact on the Company’s financial statements.
ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).”  ASU 2014-09 outlines a single model for companies to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. ASU 2014-09 will require that companies recognize revenue based on the value of transferred goods or services as they occur in the contract and will also require additional disclosures.  The new authoritative guidance will be for reporting periods after December 15, 2016, and the Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures.
ASU 2014-14, “Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) — Classification of Certain Government-Guaranteed Mortgage Loans upon Foreclosure.” ASU 2014-14 requires that certain government-guaranteed mortgage loans be derecognized and that a separate other receivable be recognized upon foreclosure if certain conditions are met. Upon foreclosure on loans that meet these criteria, a separate receivable should be recorded based on the amount of the loan balance expected to be recovered from the guarantor. The new authoritative guidance will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2014 and is not expected to have a significant impact on the Company’s financial statements.
ASU 2014-17, “Business Combinations (Topic 805): Pushdown Accounting.”  ASU 2014-17 provides guidance on whether and at what threshold an acquired entity can apply pushdown accounting in its separate financial statements upon occurrence of an event in which an acquirer obtains control of the acquired entity.  The new authoritative guidance became effective upon issuance on November 18, 2014 and had no impact on the Company’s financial statements.

Cash_and_Due_from_Banks

Cash and Due from Banks	12 Months Ended
	Dec. 31, 2014
Cash and Due from Banks
Cash and Due from Banks
	Note 2.  Cash and Due from Banks
	The Bank is required to maintain certain cash reserve balances with the Federal Reserve Bank of Chicago, which may be offset by cash on hand. The required reserve balances as of December 31, 2014 and 2013 were approximately $12.3 million and $5.3 million, respectively.
	The Company maintains its cash in deposit accounts which, at times, may exceed federally insured limits. The Company has not experienced any losses in such accounts. Management believes the Company is not exposed to any significant credit risk on cash and cash equivalents.

Securities

Securities	12 Months Ended
	Dec. 31, 2014
Securities
Securities
	Note 3.  Securities
	The amortized cost, unrealized gains and losses and fair values of securities classified as available for sale and held to maturity are summarized as follows:
					Gross			Gross
		Amortized			Unrealized			Unrealized			Fair
		Cost			Gains			Losses			Value
		(dollars in thousands)
	December 31, 2014:
	Available for sale
	U.S. Treasury securities	$	50,280		$	328		$	(2	)	$	50,606
	Obligations of U.S. government corporations and agencies	166,207			981			(178		)	167,010
	Obligations of states and political subdivisions	218,250			2,672			(761		)	220,161
	Residential mortgage-backed securities	230,596			5,062			(22		)	235,636
	Corporate debt securities	79,087			296			(76		)	79,307
	Total debt securities	744,420			9,339			(1,039		)	752,720
	Mutual funds and other equity securities	4,944			1,401			—			6,345
	Total	$	749,364		$	10,740		$	(1,039	)	$	759,065
	Held to maturity
	Obligations of states and political subdivisions	$	1,359		$	15		$	(3	)	$	1,371
	Commercial mortgage-backed securities	1,014			40			—			1,054
	Total	$	2,373		$	55		$	(3	)	$	2,425
					Gross			Gross
		Amortized			Unrealized			Unrealized			Fair
		Cost			Gains			Losses			Value
		(dollars in thousands)
	December 31, 2013:
	Available for sale
	U.S. Treasury securities	$	102,463		$	244		$	(67	)	$	102,640
	Obligations of U.S. government corporations and agencies	254,998			2,741			(328		)	257,411
	Obligations of states and political subdivisions	272,077			2,887			(2,812		)	272,152
	Residential mortgage-backed securities	174,699			3,571			(535		)	177,735
	Corporate debt securities	25,384			155			(33		)	25,506
	Total debt securities	829,621			9,598			(3,775		)	835,444
	Mutual funds and other equity securities	4,114			1,752			—			5,866
	Total	$	833,735		$	11,350		$	(3,775	)	$	841,310
	Held to maturity
	Obligations of states and political subdivisions	$	834		$	1		$	(4	)	$	831
	Total	$	834		$	1		$	(4	)	$	831
	The amortized cost and fair value of debt securities available for sale and held to maturity as of December 31, 2014, by contractual maturity, are shown below.  Mutual funds and other equity securities do not have stated maturity dates and therefore are not included in the following maturity summary.  Mortgages underlying the residential mortgage-backed securities may be called or prepaid without penalties; therefore, actual maturities could differ from the contractual maturities. All residential mortgage-backed securities were issued by U.S. government agencies and corporations.
		Available for sale						Held to maturity
		Amortized			Fair			Amortized			Fair
		Cost			Value			Cost			Value
		(dollars in thousands)						(dollars in thousands)
	Due in one year or less	$	125,672		$	126,252		$	72		$	72
	Due after one year through five years	347,781			349,168			636			636
	Due after five years through ten years	120,891			124,483			1,665			1,717
	Due after ten years	150,076			152,817			—			—
	Total	$	744,420		$	752,720		$	2,373		$	2,425
	Realized gains and losses related to sales of securities available for sale are summarized as follows:
		For the Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Gross security gains	$	807		$	599		$	1,602
	Gross security (losses)	(31		)	(46		)	(5		)
	Net security gains	$	776		$	553		$	1,597
	The tax provision for these net realized gains and losses was $0.3 million for the year ended December 31, 2014, $0.2 million for the year ended December 31, 2013, and $0.6 million for the year ended December 31, 2012.
	Investment securities with carrying amounts of $536.2 million and $428.7 million on December 31, 2014 and 2013, respectively, were pledged as collateral on public deposits, securities sold under agreements to repurchase and for other purposes as required or permitted by law.
	Information pertaining to securities with gross unrealized losses at December 31, 2014 and 2013 aggregated by investment category and length of time that individual securities have been in a continuous loss position follows:
		Continuous unrealized						Continuous unrealized					Total, gross
		losses existing for less than						losses existing for greater
		12 months, gross						than 12 months, gross
		Fair			Unrealized			Fair			Unrealized		Fair		Unrealized
		Value			Losses			Value			Losses		Value		Losses
		(dollars in thousands)
December 31, 2014:
Available for sale
U.S. Treasury securities	$	—		$	—		$	366		$	2	$	366	$	2
Obligations of U.S. government corporations and agencies	—			—			25,118			178		25,118		178
Obligations of states and political subdivisions	40,385			140			40,201			621		80,586		761
Residential mortgage-backed securities	10,630			22			—			—		10,630		22
Corporate debt securities	16,400			72			213			4		16,613		76
Total temporarily impaired Securities	$	67,415		$	234		$	65,898		$	805	$	133,313	$	1,039
Held to maturity
Obligations of states and political subdivisions	$	534		$	3		$	—		$	—	$	534	$	3
Total temporarily impaired Securities	$	534		$	3		$	—		$	—	$	534	$	3
	Continuous unrealized						Continuous unrealized					Total, gross
	losses existing for less than						losses existing for greater
	12 months, gross						than 12 months, gross
	Fair			Unrealized			Fair			Unrealized		Fair		Unrealized
	Value			Losses			Value			Losses		Value		Losses
	(dollars in thousands)
December 31, 2013:
Available for sale
U.S. Treasury securities	$	25,830		$	67		$	—		$	—	$	25,830	$	67
Obligations of U.S. government corporations and agencies	25,946			328			—			—		25,946		328
Obligations of states and political subdivisions	92,703			2,518			8,492			294		101,195		2,812
Residential mortgage-backed securities	53,543			535			—			—		53,543		535
Corporate debt securities	1,614			33			—			—		1,614		33
Total temporarily impaired Securities	$	199,636		$	3,481		$	8,492		$	294	$	208,128	$	3,775
Held to maturity
Obligations of states and political subdivisions	$	597		$	4		$	—		$	—	$	597	$	4
Total temporarily impaired Securities	$	597		$	4		$	—		$	—	$	597	$	4
Management evaluates securities for other-than-temporary impairment at least on a quarterly basis, and more frequently when economic or market concerns warrant such evaluation.  Consideration is given to the length of time and extent to which the fair value has been less than cost, the financial condition and near-term prospects of the issuer, and whether the Company has the intent to sell the security and it is more likely than not it will have to sell the security before recovery of its cost basis.
The total number of securities in the investment portfolio in an unrealized loss position as of December 31, 2014 was 202, and represented a loss of 0.8% of the aggregate carrying value. Based upon a review of unrealized loss circumstances, the unrealized losses resulted from changes in market interest rates and liquidity, not from changes in the probability of receiving the contractual cash flows. The Company does not intend to sell the securities and it is more likely than not that the Company will recover the amortized cost prior to being required to sell the securities.  Full collection of the amounts due according to the contractual terms of the securities is expected; therefore, the Company does not consider these investments to be other-than-temporarily impaired at December 31, 2014.
The Company had available for sale obligations of state and political subdivisions with a fair value of $220.2 million and $272.2 million as of December 31, 2014 and 2013, respectively.  In addition, the Company had held to maturity obligations of state and political subdivisions totaling $1.4 million and $0.8 million at December 31, 2014 and 2013, respectively.
As of December 31, 2014, the Company’s obligations of state and political subdivisions portfolio was comprised of $183.7 million of general obligation bonds and $37.9 million of revenue bonds issued by 220 issuers, primarily consisting of states, counties, cities, towns, villages and school districts.  The Company held investments in general obligation bonds in 23 states (including the District of Columbia), including seven states in which the aggregate fair value exceeded $5.0 million.  The Company held investments in revenue bonds in 15 states, including two states where the aggregate fair value exceeded $5.0 million.
As of December 31, 2013, the Company’s obligations of state and political subdivisions portfolio was comprised of $223.5 million of general obligation bonds and $49.5 million of revenue bonds issued by 267 issuers, primarily consisting of states, counties, cities, towns, villages and school districts.  The Company held investments in general obligation bonds in 25 states (including the District of Columbia), including seven states in which the aggregate fair value exceeded $5.0 million.  The Company held investments in revenue bonds in 21 states, including two states where the aggregate fair value exceeded $5.0 million.
The amortized cost and fair values of the Company’s portfolio of general obligation bonds are summarized in the following tables by the issuers’ state:
December 31, 2014:
									Average Exposure
	Number of		Amortized			Fair			Per Issuer
U.S. State	Issuers		Cost			Value			(Fair Value)
	(dollars in thousands)
Illinois	63		$	59,979		$	61,058		$	969
Wisconsin	39		36,165			36,365			932
Michigan	33		30,400			30,739			931
Pennsylvania	10		12,756			12,761			1,276
Ohio	8		9,954			9,922			1,240
Texas	7		7,364			7,313			1,045
Iowa	3		6,116			6,142			2,047
Other	24		18,862			19,370			807
Total general obligations bonds	187		$	181,596		$	183,670		$	982
December 31, 2013:
									Average Exposure
	Number of		Amortized			Fair			Per Issuer
U.S. State	Issuers		Cost			Value			(Fair Value)
	(dollars in thousands)
Illinois	82		$	82,884		$	83,804		$	1,022
Wisconsin	41		43,117			43,122			1,052
Michigan	37		35,350			35,365			956
Pennsylvania	11		14,132			14,133			1,285
Ohio	12		11,709			11,426			952
Texas	7		7,510			7,270			1,039
Iowa	3		6,126			6,060			2,020
Other	26		21,865			22,290			857
Total general obligations bonds	219		$	222,693		$	223,470		$	1,020
The general obligation bonds are diversified across many issuers, with $3.4 million and $5.0 million being the largest exposure to a single issuer at December 31, 2014 and 2013, respectively.  Accordingly, as of December 31, 2014 and 2013, the Company did not hold general obligation bonds of any single issuer, the aggregate book or market value of which exceeded 10% of the Company’s stockholders’ equity. Of the general obligation bonds in the Company’s portfolio, 97.1% had been rated by at least one nationally recognized statistical rating organization and 2.9% were unrated, based on the fair value as of December 31, 2014.  Of the general obligation bonds in the Company’s portfolio, 96.4% had been rated by at least one nationally recognized statistical rating organization and 3.6% were unrated, based on the fair value as of December 31, 2013.
The amortized cost and fair values of the Company’s portfolio of revenue bonds are summarized in the following tables by the issuers’ state:
December 31, 2014:
									Average Exposure
	Number of		Amortized			Fair			Per Issuer
U.S. State	Issuers		Cost			Value			(Fair Value)
	(dollars in thousands)
Illinois	4		$	6,772		$	6,708		$	1,677
Indiana	8		12,520			12,469			1,559
Other	21		18,721			18,685			890
Total revenue bonds	33		$	38,013		$	37,862		$	1,147
December 31, 2013:
									Average Exposure
	Number of		Amortized			Fair			Per Issuer
U.S. State	Issuers		Cost			Value			(Fair Value)
	(dollars in thousands)
Illinois	4		$	7,356		$	7,121		$	1,780
Indiana	14		14,740			14,481			1,034
Other	30		28,122			27,911			930
Total revenue bonds	48		$	50,218		$	49,513		$	1,032
The revenue bonds are diversified across many issuers and revenue sources with $3.0 million being the largest exposure to a single issuer at each of December 31, 2014 and 2013.  Accordingly, as of December 31, 2014 and 2013, the Company did not hold revenue bonds of any single issuer, the aggregate book or market value of which exceeded 10% of the Company’s stockholders’ equity.  All of the revenue bonds in the Company’s portfolio had been rated by at least one nationally recognized statistical rating organization as of December 31, 2014 and 2013.  Some of the primary types of revenue bonds owned in the Company’s portfolio include: primary education or government building lease rentals secured by ad valorem taxes, utility systems secured by utility system net revenues, housing authorities secured by mortgage loans or principal receipts on mortgage loans, secondary education secured by student fees/tuitions, and pooled issuances (i.e. bond bank) consisting of multiple underlying municipal obligors.
Substantially all of the Company’s obligations of state and political subdivision securities are owned by Busey Bank,  whose investment policy requires that state and political subdivision securities purchased be investment grade.  Busey Bank’s investment policy also limits the amount of rated state and political subdivision securities to an aggregate 100% of the Bank’s Total Risk Based Capital at the time of purchase and an aggregate 15% of Total Risk Based Capital for unrated state and political subdivision securities issued by municipalities having taxing authority or located in counties/micropolitan statistical areas/metropolitan statistical areas in which an office of the Bank is located.  The investment policy states fixed income investments that are not Office of the Comptroller of the Currency Type 1 securities (U.S. Treasuries, agencies, municipal government general obligation and, for well-capitalized institutions, most municipal revenue bonds) should be analyzed prior to acquisition to determine that (1) the security has low risk of default by the obligor, and (2) the full and timely repayment of principal and interest is expected over the expected life of the investment.  All securities in the Bank’s obligations of state and political subdivision securities portfolio are subject to ongoing review.  Factors that may be considered as part of ongoing monitoring of state and political subdivision securities include credit rating changes by nationally recognized statistical rating organizations, market valuations, third-party municipal credit analysis, which may include indicative information regarding the issuer’s capacity to pay, market and economic data and such other factors as are available and relevant to the security or the issuer such as its budgetary position and sources, strength and stability of taxes and/or other revenue.
As of December 31, 2014, the Company’s regular monitoring of its obligations of state and political subdivisions portfolio had not uncovered any facts or circumstances resulting in significantly different credit ratings than those assigned by a nationally recognized statistical rating organization.

Loans

Loans	12 Months Ended
	Dec. 31, 2014
Loans
Loans
	Note 4.  Loans
	Geographic distributions of loans were as follows:
			December 31, 2014
			Illinois			Florida			Indiana			Total
			(dollars in thousands)
	Commercial		$	554,779		$	16,739		$	30,242		$	601,760
	Commercial real estate		811,034			171,243			121,874			1,104,151
	Real estate construction		60,994			17,950			28,110			107,054
	Retail real estate		473,171			106,658			12,644			592,473
	Retail other		9,690			562			—			10,252
	Total		$	1,909,668		$	313,152		$	192,870		$	2,415,690
	Less held for sale(1)											10,400
												$	2,405,290
	Less allowance for loan losses											47,453
	Net loans											$	2,357,837
	(1) Loans held for sale are included in retail real estate.
			December 31, 2013
			Illinois			Florida			Indiana			Total
			(dollars in thousands)
	Commercial		$	530,174		$	20,536		$	29,902		$	580,612
	Commercial real estate		800,568			160,255			131,450			1,092,273
	Real estate construction		55,190			17,426			6,239			78,855
	Retail real estate		419,801			103,104			11,588			534,493
	Retail other		8,422			552			93			9,067
	Total		$	1,814,155		$	301,873		$	179,272		$	2,295,300
	Less held for sale(1)											13,840
												$	2,281,460
	Less allowance for loan losses											47,567
	Net loans											$	2,233,893
	(1) Loans held for sale are included in retail real estate.
	Net deferred loan origination costs included in the tables above were $0.6 million as of December 31, 2014 and insignificant as of December 31, 2013.
	The Company believes that making sound loans are a necessary and desirable means of employing funds available for investment. Recognizing the Company’s obligations to its stockholders, depositors, and to the communities it serves, authorized personnel are expected to seek to develop and make sound, profitable loans that resources permit and that opportunity affords. The Company maintains lending policies and procedures designed to focus lending efforts on the types, locations and duration of loans most appropriate for its business model and markets.  While not specifically limited, the Company attempts to focus its lending on short to intermediate-term (0-7 years) loans in geographies within 125 miles of its lending offices.  The Company attempts to utilize government-assisted lending programs, such as the Small Business Administration and United States Department of Agriculture lending programs, when prudent. Generally, loans are collateralized by assets, primarily real estate, of the borrowers and guaranteed by individuals.  The loans are expected to be repaid primarily from cash flows of the borrowers, or from proceeds from the sale of selected assets of the borrowers.
	Management reviews and approves the Company’s lending policies and procedures on a routine basis.  Management routinely (at least quarterly) reviews the Company’s allowance for loan losses and reports related to loan production, loan quality, concentrations of credit, loan delinquencies and non-performing and potential problem loans. The Company’s underwriting standards are designed to encourage relationship banking rather than transactional banking.  Relationship banking implies a primary banking relationship with the borrower that includes, at a minimum, an active deposit banking relationship in addition to the lending relationship.  The integrity and character of the borrower are significant factors in the Company’s loan underwriting.  As a part of underwriting, tangible positive or negative evidence of the borrower’s integrity and character are sought out.  Additional significant underwriting factors beyond location, duration, a sound and profitable cash flow basis and the borrower’s character are the quality of the borrower’s financial history, the liquidity of the underlying collateral and the reliability of the valuation of the underlying collateral.
	Total borrowing relationships, including direct and indirect debt, are generally limited to $20 million, which is significantly less than the Company’s regulatory lending limit.  Borrowing relationships exceeding $20 million are reviewed by the Company’s board of directors at least annually and more frequently by management.  At no time is a borrower’s total borrowing relationship permitted to exceed the Company’s regulatory lending limit.  Loans to related parties, including executive officers and the Company’s various directorates, are reviewed for compliance with regulatory guidelines by the Company’s board of directors at least annually.
	The Company maintains an independent loan review department that reviews the loans for compliance with the Company’s loan policy on a periodic basis.  In addition to compliance with this policy, the loan review process reviews the risk assessments made by the Company’s credit department, lenders and loan committees. Results of these reviews are presented to management and the audit committee at least quarterly.
	The Company’s lending can be summarized into five primary areas: commercial loans, commercial real estate loans, real estate construction loans, retail real estate loans, and retail other loans. The significant majority of the lending activity occurs in the Company’s Illinois and Indiana markets, with the remainder in the Florida market.  Due to the small scale of the Indiana loan portfolio and its geographical proximity to the Illinois portfolio, the Company believes that quantitative or qualitative segregation between Illinois and Indiana is not material or warranted.
	Commercial Loans
	Commercial loans typically comprise working capital loans or business expansion loans, including loans for asset purchases and other business loans.  Commercial loans will generally be guaranteed in full or a significant amount by the primary owners of the business. Commercial loans are made based primarily on the historical and projected cash flow of the underlying borrower and secondarily on the underlying assets pledged as collateral by the borrower.  The cash flows of the underlying borrower, however, may not perform consistently with historical or projected information.  Further, the collateral securing loans may fluctuate in value due to individual economic or other factors.  The Company has established minimum standards and underwriting guidelines for all commercial loan types.
	Commercial Real Estate Loans
	The Company is primarily located in markets with significant academic presence.  The academic presence in addition to the commercial environment provides for the majority of the Company’s commercial lending opportunities to be commercial real estate related, including multi-unit housing.  As the majority of the Company’s loan portfolio is within the commercial real estate class, the Company’s goal is to maintain a high quality, geographically diverse portfolio of commercial real estate loans. Commercial real estate loans are subject to underwriting standards and guidelines similar to commercial loans.  Commercial real estate loans will generally be guaranteed in full or a significant amount by the primary owners of the business. The repayment of these loans is primarily dependent on the cash flows of the underlying property. However, the commercial real estate loan generally must be supported by an adequate underlying collateral value.  The performance and the value of the underlying property may be adversely affected by economic factors or geographical and/or industry specific factors.  These loans are subject to other industry guidelines that are closely monitored by the Company.
	Real Estate Construction Loans
	Real estate construction loans are typically commercial in nature. The loan proceeds are controlled by the Company and distributed for the improvement of real estate in which the Company holds a mortgage.  Real estate construction loans will generally be guaranteed in full or a significant amount by the developer or primary owners of the business. These loans are subject to underwriting standards and guidelines similar to commercial loans. The loan generally must be supported by an adequate “as completed” value of the underlying project. In addition to the underlying project, the financial history of the developer and business owners weighs significantly in determining approval. The repayment of these loans is typically through permanent financing following completion of the construction.  Real estate construction loans are inherently more risky than loans on completed properties as the unimproved nature and the financial risks of construction significantly enhance the risks of commercial real estate loans.  These loans are closely monitored and subject to other industry guidelines.
	Retail Real Estate Loans
	Retail real estate loans are comprised of direct consumer loans that include residential real estate, residential real estate construction loans, home equity lines of credit and home equity loans.  The Company sells substantially all of its fixed rate long-term (over 15 years) retail real estate loans to secondary market purchasers.  The Company does retain fixed rate retail real estate loans having terms typically 15 years or less.  As retail real estate loan underwriting is subject to specific regulations, the Company typically underwrites its retail real estate loans to conform to widely accepted standards.  Several factors are considered in underwriting including the value of the underlying real estate and the debt to income and credit history of the borrower.
	Retail Other Loans
	Retail other loans consist of installment loans to individuals, including automotive loans.  These loans are centrally underwritten utilizing the borrower’s financial history, including the Fair Isaac Corporation (FICO) credit scoring and information as to the underlying collateral. Repayment is expected from the cash flow of the borrower.
	The Company utilizes a loan grading scale to assign a risk grade to all of its loans.  Loans are graded on a scale of 1 through 10 with grades 2, 4 & 5 unused.  A description of the general characteristics of the grades is as follows:
		·		Grades 1, 3, 6- These grades include loans which are all considered strong credits, with grade 1 being investment or near investment grade.  A grade 3 loan is comprised of borrowers that exhibit credit fundamentals that exceed industry standards and loan policy guidelines. A grade 6 loan is comprised of borrowers that exhibit acceptable credit fundamentals.
		·		Grade 7- This grade includes loans on management’s “Watch List” and is intended to be utilized on a temporary basis for a pass grade borrower where a significant risk-modifying action is anticipated in the near future.
		·		Grade 8- This grade is for “Other Assets Specially Mentioned” loans that have potential weaknesses which may, if not checked or corrected, weaken the asset or inadequately protect the Company’s credit position at some future date.
		·		Grade 9- This grade includes “Substandard” loans, in accordance with regulatory guidelines, for which the accrual of interest has not been stopped.  Assets so classified must have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt.  They are characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected.
		·		Grade 10- This grade includes “Doubtful” loans that have all the characteristics of a substandard loan with additional factors that make collection in full highly questionable and improbable. Such loans are placed on non-accrual status and may be dependent on collateral having a value that is difficult to determine.
	All loans are graded at the inception of the loan.  All commercial loans that are $1.0 million or less are processed through an expedited underwriting process.  If the credit receives a pass grade it is aggregated into a homogenous pool of either:  $0.35 million or less or $0.35 million to $1.0 million.  These pools are monitored on a quarterly basis for the first year, semiannually in the second year and annually thereafter.  Homogenous pool credits which are subsequently downgraded to a grading of 7 or worse are subject to the same portfolio review as loans over $1.0 million.  All commercial loans greater than $1.0 million receive a portfolio review at least annually.  Commercial loans greater than $1.0 million that have a grading of 7 receive a portfolio review twice per year.  Commercial loans greater than $1.0 million that have a grading of 8 or worse receive a portfolio review on a quarterly basis.  Interim grade reviews may take place if circumstances of the borrower warrant a more timely review.
	Loans in the highest grades, represented by grades 1, 3, 6 and 7, totaled $2.28 billion at December 31, 2014 and grew by $160.9 million from $2.12 billion at December 31, 2013.  Loans in the lowest grades, represented by grades 8, 9 and 10, totaled $124.0 million at December 31, 2014 and declined by $37.9 million from $161.9 million at December 31, 2013.  The positive change in mix of loan grades began in 2012 and suggests a declining level of overall risk in the total loan portfolio.
	The following table presents weighted average risk grades segregated by category of loans (excluding held for sale, non-posted and clearings) and geography:
			December 31, 2014
			Weighted Avg.		Grades			Grade			Grade			Grade			Grade
			Risk Grade		1, 3, 6			7			8			9			10
			(dollars in thousands)
	Illinois/Indiana
	Commercial		4.80		$	542,796		$	27,032		$	8,549		$	5,498		$	1,146
	Commercial real estate		5.67		819,708			64,975			25,719			19,821			2,685
	Real estate construction		5.91		71,074			5,332			11,448			1,204			46
Retail real estate		3.46		453,560			10,478			4,569			3,179			1,414
Retail other		3.21		9,632			26			24			—			8
Total Illinois/Indiana				$	1,896,770		$	107,843		$	50,309		$	29,702		$	5,299
Florida
Commercial		5.40		$	13,455		$	105		$	78		$	1,459		$	1,642
Commercial real estate		6.00		123,807			25,520			6,002			15,404			510
Real estate construction		6.21		16,475			—			615			842			18
Retail real estate		4.09		82,185			11,686			9,601			1,031			1,531
Retail other		2.94		562			—			—			—			—
Total Florida				$	236,484		$	37,311		$	16,296		$	18,736		$	3,701
Total				$	2,133,254		$	145,154		$	66,605		$	48,438		$	9,000
		December 31, 2013
		Weighted Avg.		Grades			Grade			Grade			Grade			Grade
		Risk Grade		1, 3, 6			7			8			9			10
		(dollars in thousands)
Illinois/Indiana
Commercial		4.66		$	487,587		$	46,992		$	15,986		$	8,536		$	975
Commercial real estate		5.55		799,117			79,371			19,327			29,606			4,597
Real estate construction		7.11		21,585			16,376			11,920			7,686			3,862
Retail real estate		3.53		393,299			9,285			5,392			4,408			3,936
Retail other		2.64		8,451			60			—			4			—
Total Illinois/Indiana				$	1,710,039		$	152,084		$	52,625		$	50,240		$	13,370
Florida
Commercial		5.89		$	16,460		$	174		$	3,218		$	684		$	—
Commercial real estate		6.02		116,741			16,470			11,250			12,721			3,073
Real estate construction		6.64		7,886			7,961			743			836			—
Retail real estate		3.85		77,116			12,052			9,417			3,050			721
Retail other		1.72		552			—			—			—			—
Total Florida				$	218,755		$	36,657		$	24,628		$	17,291		$	3,794
Total				$	1,928,794		$	188,741		$	77,253		$	67,531		$	17,164
Loans are considered past due if the required principal and interest payments have not been received as of the date such payments were due.  Loans are placed on non-accrual status when, in management’s opinion, the borrower may be unable to meet payment obligations as they become due, as well as when required by regulatory provisions.  Loans may be placed on non-accrual status regardless of whether or not such loans are considered past due.  When interest accrual is discontinued, all unpaid accrued interest is reversed.  Interest income is subsequently recognized only to the extent cash payments are received in excess of the principal due.  Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured.
An age analysis of past due loans still accruing and non-accrual loans is as follows:
		December 31, 2014
		Loans past due, still accruing									Non-accrual
		30-59 Days			60-89 Days			90+Days			Loans
		(dollars in thousands)
Illinois/Indiana
Commercial		$	15		$	105		$	—		$	1,146
Commercial real estate		1,068			—			10			2,685
Real estate construction		—			—			—			46
Retail real estate		488			128			—			1,414
Retail other		15			—			—			8
Total Illinois/Indiana		$	1,586		$	233		$	10		$	5,299
Florida
Commercial		$	—		$	—		$	—		$	1,642
Commercial real estate		—			—			—			510
Real estate construction		—			—			—			18
Retail real estate		—			—			—			1,531
Retail other		—			—			—			—
Total Florida		$	—		$	—		$	—		$	3,701
Total		$	1,586		$	233		$	10		$	9,000
		December 31, 2013
		Loans past due, still accruing									Non-accrual
		30-59 Days			60-89 Days			90+Days			Loans
		(dollars in thousands)
Illinois/Indiana
Commercial		$	906		$	279		$	92		$	975
Commercial real estate		567			3,736			—			4,597
Real estate construction		—			—			—			3,862
Retail real estate		483			123			103			3,936
Retail other		20			—			—			—
Total Illinois/Indiana		$	1,976		$	4,138		$	195		$	13,370
Florida
Commercial		$	—		$	—		$	—		$	—
Commercial real estate		—			—			—			3,073
Real estate construction		—			—			—			—
Retail real estate		—			—			—			721
Retail other		—			—			—			—
Total Florida		$	—		$	—		$	—		$	3,794
Total		$	1,976		$	4,138		$	195		$	17,164
A loan is impaired when, based on current information and events, it is probable the Company will be unable to collect scheduled principal and interest payments when due according to the terms of the loan agreement.  Factors considered by management in determining impairment include payment status, collateral value, and the probability of collecting scheduled principal and interest payments when due.  Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired.  Management determines the significance of payment delays and payment shortfalls on a case-by-case basis, taking into consideration all of the circumstances surrounding the loan and the borrower, including the length of the delay, the reasons for the delay, the borrower’s prior payment record, and the amount of the shortfall in relation to the principal and interest owed.  The following loans are assessed for impairment by the Company: loans 60 days or more past due and over $0.25 million, loans graded 8 over $0.5 million and loans graded 9 or 10.
Impairment is measured on a loan-by-loan basis for commercial and construction loans by either the present value of the expected future cash flows discounted at the loan’s effective interest rate, the loan’s observable market price, or the fair value of the collateral if the loan is collateral dependent.  Large groups of smaller balance homogenous loans are collectively evaluated for impairment.  Accordingly, the Company does not separately identify individual consumer and residential loans for impairment disclosures unless such loans are the subject of a restructuring agreement.
The Company actively seeks to reduce its investment in impaired loans.  The primary tools to work through impaired loans are settlement with the borrowers or guarantors, foreclosure of the underlying collateral, loan sales to outside parties or restructuring.  During the years ended December 31, 2014 and 2013, the Company sold problem loans from its portfolio, net of charge-offs, of $3.8 million and $7.6 million, respectively.
The gross interest income that would have been recorded in the years ended December 31, 2014, 2013 and 2012 if impaired loans had been current in accordance with their original terms was $0.8 million, $1.3 million, and $3.4 million, respectively.  The amount of interest collected on those loans and recognized on a cash basis that was included in interest income was insignificant in 2014, 2013 and 2012.
The Company’s loan portfolio includes certain loans that have been modified in a troubled debt restructuring (“TDR”), where concessions have been granted to borrowers who have experienced financial difficulties. The Company will restructure loans for its customers who appear to be able to meet the terms of their loan over the long term, but who may be unable to meet the terms of the loan in the near term due to individual circumstances.
The Company considers the customer’s past performance, previous and current credit history, the individual circumstances surrounding the current difficulties and the customer’s plan to meet the terms of the loan in the future prior to restructuring the terms of the loan.  Generally, all five primary areas of lending are restructured through short-term interest rate relief, short-term principal payment relief, short-term principal and interest payment relief, or forbearance (debt forgiveness).  Once a restructured loan has gone 90+ days past due or is placed on non-accrual status, it is included in the non-performing loan totals. A summary of restructured loans as of December 31, 2014 and 2013 is as follows:
		December 31,			December 31,
		2014			2013
		(dollars in thousands)
Restructured loans:
In compliance with modified terms		$	11,866		$	11,511
30 – 89 days past due		—			380
Included in non-performing loans		1,126			5,919
Total		$	12,992		$	17,810
All TDRs are considered to be impaired for purposes of assessing the adequacy of the allowance for loan losses and for financial reporting purposes.  When the Company modifies a loan in a TDR, it evaluates any possible impairment similar to other impaired loans based on present value of the expected future cash flows discounted at the loan’s effective interest rate, the loan’s observable market price, or the fair value of the collateral if the loan is collateral dependent.  If the Company determines that the value of the TDR is less than the recorded investment in the loan, impairment is recognized through an allowance estimate in the period of the modification and in periods subsequent to the modification.
Performing loans classified as TDRs during the three and twelve months ended December 31, 2014 included one commercial real estate modification in Florida for short-term principal payment relief, with a recorded investment of $2.0 million.  Other performing loans classified as TDRs during the twelve months ended December 31, 2014 were insignificant.
Performing loans classified as TDRs during the three and twelve months ended December 31, 2013 included one commercial modification in Illinois/Indiana for short-term principal payment relief, with a recorded investment of $0.1 million.  Further, one commercial real estate modification in Illinois/Indiana for the three and twelve months ended December 31, 2013 consisted of a modification for short-term principal payment relief, with a recorded investment of $0.2 million. Commercial real estate modifications for the twelve months ended December 31, 2013 also consisted of one modification in Illinois/Indiana for short-term principal payment relief, with a recorded investment of $0.2 million and one modification in Florida for short-term interest rate relief, with a recorded investment of $0.1 million.  Other performing loans classified as TDRs during the three and twelve months ended December 31, 2013 were insignificant.
The gross interest income that would have been recorded in the three and twelve months ended December 31, 2014 and 2013 if performing TDRs had been in accordance with their original terms instead of modified terms was insignificant.
TDRs that were classified as non-performing and had payment defaults (a default occurs when a loan is 90 days or more past due or transferred to non-accrual) during the three and twelve months ended December 31, 2014 consisted of one Illinois/Indiana commercial modification totaling $0.3 million.
There were no TDRs that were classified as non-performing and had payment defaults during the three months ended December 31, 2013.  TDRs that were classified as non-performing and had payment defaults during the twelve months ended December 31, 2013 consisted of one Illinois/Indiana commercial real estate modification totaling $1.7 million, one Illinois/Indiana real estate construction modification totaling $0.2 million and one Illinois/Indiana retail real estate modification totaling $0.5 million.
The following tables provide details of impaired loans, segregated by category and geography. The unpaid contractual principal balance represents the recorded balance prior to any partial charge-offs.  The recorded investment represents customer balances net of any partial charge-offs recognized on the loan.  The average recorded investment is calculated using the most recent four quarters.
		December 31, 2014
		Unpaid			Recorded			Recorded			Total			Related			Average
		Contractual			Investment			Investment			Recorded			Allowance			Recorded
		Principal			with No			with Allowance			Investment						Investment
		Balance			Allowance
		(dollars in thousands)
Illinois/Indiana
Commercial		$	2,944		$	1,376		$	741		$	2,117		$	595		$	2,479
Commercial real estate		4,007			1,140			2,854			3,994			1,975			5,473
Real estate construction		46			—			46			46			46			2,269
Retail real estate		2,794			2,403			25			2,428			25			3,061
Retail other		8			8			—			8			—			2
Total Illinois/Indiana		$	9,799		$	4,927		$	3,666		$	8,593		$	2,641		$	13,284
Florida
Commercial		$	2,742		$	1,642		$	—		$	1,642		$	—		$	330
Commercial real estate		5,775			4,414			1,274			5,688			370			5,032
Real estate construction		620			551			—			551			—			485
Retail real estate		11,181			9,755			350			10,105			150			9,532
Retail other		7			—			7			7			7			5
Total Florida		$	20,325		$	16,362		$	1,631		$	17,993		$	527		$	15,384
Total		$	30,124		$	21,289		$	5,297		$	26,586		$	3,168		$	28,668
		December 31, 2013
		Unpaid			Recorded			Recorded			Total			Related			Average
		Contractual			Investment			Investment			Recorded			Allowance			Recorded
		Principal			with No			with Allowance			Investment						Investment
		Balance			Allowance
		(dollars in thousands)
Illinois/Indiana
Commercial		$	2,825		$	1,684		$	602		$	2,286		$	485		$	4,169
Commercial real estate		8,866			3,671			3,740			7,411			1,977			10,335
Real estate construction		4,932			2,292			1,570			3,862			468			5,889
Retail real estate		5,583			3,267			2,010			5,277			604			5,296
Retail other		—			—			—			—			—			—
Total Illinois/Indiana		$	22,206		$	10,914		$	7,922		$	18,836		$	3,534		$	25,689
Florida
Commercial		$	—		$	—		$	—		$	—		$	—		$	—
Commercial real estate		7,108			3,946			1,319			5,265			416			6,662
Real estate construction		417			417			—			417			—			1,294
Retail real estate		10,346			9,005			537			9,542			337			11,079
Retail other		—			—			—			—			—			—
Total Florida		$	17,871		$	13,368		$	1,856		$	15,224		$	753		$	19,035
Total		$	40,077		$	24,282		$	9,778		$	34,060		$	4,287		$	44,724
Management’s opinion as to the ultimate collectability of loans is subject to estimates regarding future cash flows from operations and the value of property, real and personal, pledged as collateral.  These estimates are affected by changing economic conditions and the economic prospects of borrowers.
Allowance for Loan Losses
The allowance for loan losses represents an estimate of the amount of losses believed inherent in the Company’s loan portfolio at the balance sheet date.  The allowance for loan losses is evaluated geographically, by class of loans.  The allowance calculation involves a high degree of estimation that management attempts to mitigate through the use of objective historical data where available. Loan losses are charged against the allowance for loan losses when management believes the uncollectibility of the loan balance is confirmed.  Subsequent recoveries, if any, are credited to the allowance.  Overall, the Company believes the allowance methodology is consistent with prior periods and the balance was adequate to cover the estimated losses in the Company’s loan portfolio at December 31, 2014 and 2013.
The general portion of the Company’s allowance contains two components: (i) a component for historical loss ratios, and (ii) a component for adversely graded loans.  The historical loss ratio component is an annualized loss rate calculated using a sum-of-years digits weighted 20-quarter historical average.
The Company’s component for adversely graded loans attempts to quantify the additional risk of loss inherent in the grade 8 and grade 9 portfolios.  The grade 9 portfolio has an additional allocation placed on those loans determined by a one-year charge-off percentage for the respective loan type/geography.  The minimum additional reserve on a grade 9 loan was 3.00% as of December 31, 2014 and 2013, which is an estimate of the additional loss inherent in these loan grades based upon a review of overall historical charge-offs.  As of December 31, 2014, the Company believed this minimum reserve remained adequate.
Grade 8 loans have an additional allocation placed on them determined by the trend difference of the respective loan type/geography’s rolling 12- and 20-quarter historical loss trends. If the rolling 12-quarter average is higher (more current information) than the rolling 20-quarter average, the Company adds the additional amount to the allocation.  The minimum additional amount for grade 8 loans was 1.00% as of December 31, 2014 and 2013, based upon a review of the differences between the rolling 12 and 20 quarter historical loss averages by region.  As of December 31, 2014, the Company believed this minimum additional amount remained adequate.
The specific portion of the Company’s allowance relates to loans that are impaired, which includes non-performing loans, TDRs and other loans determined to be impaired.  The impaired loans are subtracted from the general loans and are allocated specific reserves as discussed above.
Impaired loans are reported at the fair value of the underlying collateral, less estimated costs to sell, if repayment is expected solely from the collateral. Collateral values are estimated using a combination of observable inputs, including recent appraisals discounted for collateral specific changes and current market conditions, and unobservable inputs based on customized discounting criteria.
The general quantitative allocation based upon historical charge off rates is adjusted for qualitative factors based on current general economic conditions and other qualitative risk factors both internal and external to the Company. In general, such valuation allowances are determined by evaluating, among other things:  (i) Management & Staff; (ii) Loan Underwriting, Policy and Procedures; (iii) Internal/External Audit & Loan Review; (iv) Valuation of Underlying Collateral; (v) Macro and Local Economic Factor; (vi) Impact of Competition, Legal & Regulatory Issues; (vii) Nature and Volume of Loan Portfolio; (viii) Concentrations of Credit; (ix) Net Charge-Off Trend; and (x) Non-Accrual, Past Due and Classified Trend.  Management evaluates the degree of risk that each one of these components has on the quality of the loan portfolio on a quarterly basis.  Based on each component’s risk factor, a qualitative adjustment to the reserve may be applied to the appropriate loan categories.
During the fourth quarter of 2014, the Company adjusted the Illinois/Indiana and Florida qualitative factors relating to Macro and Local Economic Factor and a Florida qualitative factor relating to Net Charge-Off Trend.  The adjustment of these factors increased our allowance requirements by $1.3 million at December 31, 2014 compared to the method used for September 30, 2014.  Earlier in 2014, the Company adjusted Illinois/Indiana qualitative factors relating to Loan Underwriting, Policy and Procedures, Macro and Local Economic Factor, Nature and Volume of Loan Portfolio, and Net Charge-Off Trend compared to the method used for December 31, 2013.  Additionally, the Company adjusted Florida qualitative factors relating to Loan Underwriting, Policy and Procedures, Macro and Local Economic Factor, and Net Charge-Off Trend compared to the method used for December 31, 2013.  Adjustments to increase these qualitative factors were made throughout 2014 to recognize perceived changing degrees of risk, offset decreasing quantitative factors and reflect management’s evaluation of risk.  The Company will continue to monitor its qualitative factors on a quarterly basis.
Changes in the allowance for loan losses were as follows:
		Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
Balance, beginning of year		$	47,567		$	48,012		$	58,506
Provision for loan losses		2,000			7,500			16,500
Loan balances charged-off		(7,371		)	(10,669		)	(30,063		)
Recoveries applicable to loan balances previously charged-off		5,257			2,724			3,069
Balance, end of year		$	47,453		$	47,567		$	48,012
The following table details activity on the allowance for loan losses.  Allocation of a portion of the allowance to one category does not preclude its availability to absorb losses in other categories.
		Year Ended December 31, 2014
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
Illinois/Indiana
Beginning balance		$	8,452		$	16,379		$	2,540		$	6,862		$	216		$	34,449
Provision for loan loss		1,048			(880		)	90			5,942			332			6,532
Charged-off		(864		)	(1,173		)	(657		)	(2,396		)	(429		)	(5,519		)
Recoveries		233			2,108			617			337			185			3,480
Ending Balance		$	8,869		$	16,434		$	2,590		$	10,745		$	304		$	38,942
Florida
Beginning balance		$	1,926		$	5,733		$	1,168		$	4,287		$	4		$	13,118
Provision for loan loss		195			(1,799		)	(1,889		)	(1,021		)	(18		)	(4,532		)
Charged-off		(1,126		)	—			(69		)	(656		)	(1		)	(1,852		)
Recoveries		177			271			995			307			27			1,777
Ending Balance		$	1,172		$	4,205		$	205		$	2,917		$	12		$	8,511
		Year Ended December 31, 2013
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
Illinois/Indiana
Beginning balance		$	6,597		$	15,023		$	2,527		$	8,110		$	322		$	32,579
Provision for loan loss		2,681			2,143			847			616			63			6,350
Charged-off		(964		)	(1,361		)	(1,212		)	(2,187		)	(511		)	(6,235		)
Recoveries		138			574			378			323			342			1,755
Ending Balance		$	8,452		$	16,379		$	2,540		$	6,862		$	216		$	34,449
Florida
Beginning balance		$	1,437		$	6,062		$	2,315		$	5,614		$	5		$	15,433
Provision for loan loss		414			2,225			(1,419		)	(51		)	(19		)	1,150
Charged-off		—			(2,543		)	(56		)	(1,828		)	(7		)	(4,434		)
Recoveries		75			(11		)	328			552			25			969
Ending Balance		$	1,926		$	5,733		$	1,168		$	4,287		$	4		$	13,118
		Year Ended December 31, 2012
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
Illinois/Indiana
Beginning balance		$	9,143		$	18,605		$	4,352		$	6,473		$	464		$	39,037
Provision for loan loss		1,428			10,058			(270		)	4,397			278			15,891
Charged-off		(4,176		)	(14,016		)	(1,883		)	(3,264		)	(636		)	(23,975		)
Recoveries		202			376			328			504			216			1,626
Ending Balance		$	6,597		$	15,023		$	2,527		$	8,110		$	322		$	32,579
Florida
Beginning balance		$	1,939		$	8,413		$	2,936		$	6,160		$	21		$	19,469
Provision for loan loss		(811		)	(619		)	(555		)	2,626			(32		)	609
Charged-off		(246		)	(1,858		)	(336		)	(3,646		)	(2		)	(6,088		)
Recoveries		555			126			270			474			18			1,443
Ending Balance		$	1,437		$	6,062		$	2,315		$	5,614		$	5		$	15,433
The following table presents the allowance for loan losses and recorded investments in loans by category and geography:
		As of December 31, 2014
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
Illinois/Indiana
Amount allocated to:
Loans individually evaluated for impairment		$	595		$	1,975		$	46		$	25		$	—		$	2,641
Loans collectively evaluated for impairment		8,274			14,459			2,544			10,720			304			36,301
Ending Balance		$	8,869		$	16,434		$	2,590		$	10,745		$	304		$	38,942
Loans:
Loans individually evaluated for impairment		$	2,117		$	3,994		$	46		$	2,428		$	8		$	8,593
Loans collectively evaluated for impairment		582,904			928,914			89,058			473,611			9,682			2,084,169
Ending Balance		$	585,021		$	932,908		$	89,104		$	476,039		$	9,690		$	2,092,762
Florida
Amount allocated to:
Loans individually evaluated for impairment		$	—		$	370		$	—		$	150		$	7		$	527
Loans collectively evaluated for impairment		1,172			3,835			205			2,767			5			7,984
Ending Balance		$	1,172		$	4,205		$	205		$	2,917		$	12		$	8,511
Loans:
Loans individually evaluated for impairment		$	1,642		$	5,688		$	551		$	10,105		$	7		$	17,993
Loans collectively evaluated for impairment		15,097			165,555			17,399			95,929			555			294,535
Ending Balance		$	16,739		$	171,243		$	17,950		$	106,034		$	562		$	312,528
		As of December 31, 2013
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
Illinois/Indiana
Amount allocated to:
Loans individually evaluated for impairment		$	485		$	1,977		$	468		$	604		$	—		$	3,534
Loans collectively evaluated for impairment		7,967			14,402			2,072			6,258			216			30,915
Ending Balance		$	8,452		$	16,379		$	2,540		$	6,862		$	216		$	34,449
Loans:
Loans individually evaluated for impairment		$	2,286		$	7,411		$	3,862		$	5,277		$	—		$	18,836
Loans collectively evaluated for impairment		557,790			924,607			57,567			413,020			8,515			1,961,499
Ending Balance		$	560,076		$	932,018		$	61,429		$	418,297		$	8,515		$	1,980,335
Florida
Amount allocated to:
Loans individually evaluated for impairment		$	—		$	416		$	—		$	337		$	—		$	753
Loans collectively evaluated for impairment		1,926			5,317			1,168			3,950			4			12,365
Ending Balance		$	1,926		$	5,733		$	1,168		$	4,287		$	4		$	13,118
Loans:
Loans individually evaluated for impairment		$	—		$	5,265		$	417		$	9,542		$	—		$	15,224
Loans collectively evaluated for impairment		20,536			154,990			17,009			92,814			552			285,901
Ending Balance		$	20,536		$	160,255		$	17,426		$	102,356		$	552		$	301,125

Loan_Servicing

Loan Servicing	12 Months Ended
	Dec. 31, 2014
Loan Servicing
Loan Servicing
	Note 5.  Loan Servicing
	The unpaid principal balances of loans serviced by the Company for the benefit of others are not included in the accompanying Consolidated Balance Sheets. These unpaid principal balances were $1.39 billion and $1.44 billion as of December 31, 2014 and 2013, respectively. Servicing loans for others generally consists of collecting mortgage payments, maintaining escrow accounts, disbursing payments to investors and collection and foreclosure processing.  Loan servicing income is recorded on the accrual basis and includes servicing fees from investors and certain charges collected from borrowers, such as late payment fees, and is net of amortization of capitalized mortgage servicing rights.
	The balance of capitalized servicing rights included in other assets at December 31, 2014 and 2013, was $3.9 million and $5.1 million, respectively. The fair values of these servicing rights were $5.2 million and $6.4 million, respectively, at December 31, 2014 and 2013.  The following summarizes mortgage servicing rights capitalized and amortized:
		For the Years Ended December 31,
		2014		2013		2012
		(dollars in thousands)
	Mortgage servicing rights capitalized	$	983	$	2,490	$	2,794
	Mortgage servicing rights amortized	$	2,228	$	2,650	$	2,972

Premises_and_Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2014
Premises and Equipment
Premises and Equipment
	Note 6.  Premises and Equipment
	Premises and equipment are summarized as follows:
		December 31,
		2014		2013
		(dollars in thousands)
	Land and improvements	$	21,559	$	21,532
	Buildings and improvements	62,794		62,159
	Furniture and equipment	32,018		33,622
		116,371		117,313
	Less accumulated depreciation	52,397		51,486
	Total premises and equipment	$	63,974	$	65,827
	Depreciation expense was $5.6 million, $5.5 million, and $5.4 million for the years ended December 31, 2014, 2013 and 2012, respectively.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2014
Goodwill and Other Intangible Assets
Goodwill and Other Intangible Assets
	Note 7: Goodwill and Other Intangible Assets
	Other than goodwill, the Company does not have any other intangible assets that are not amortized. Accounting standards allow for goodwill to be tested for impairment by first performing a qualitative assessment to determine whether it is more likely than not that the fair value of the reporting unit is less than its carrying value.  If the reporting unit does not pass the qualitative assessment, then the reporting unit’s carrying value is compared to its fair value.
	The Company’s goodwill is associated with the operations of Busey Wealth Management and FirsTech.  Based on the impairment testing performed at December 31, 2014, Busey Wealth Management and FirsTech did not have indicators of potential impairment based on the estimated fair value of those operating segments. Busey Wealth Management and FirsTech have sustained quarterly and annual profits. However, it is possible we will evaluate our goodwill for impairment on a more frequent basis than annually. The evaluation may result in impairment.
	There were no changes in the carrying amount of goodwill by operating segment during 2014 or 2013. The carrying amount of goodwill by operating segment, in thousands, at December 31, 2014 and 2013 is as follows:
	Goodwill:
	FirsTech	$	8,992
	Busey Wealth Management	11,694
	Total Goodwill	$	20,686
	Core deposit and customer relationship intangible assets are amortized on an accelerated or straight-line basis over the estimated period benefited up to 10 years.  Other intangible asset disclosures are as follows:
		Balance at		Amortization		Balance at
		December 31,				December 31,
		2013				2014
		(dollars in thousands)
	Amortized intangible assets:
	Core deposit intangible assets	$	6,124	$	1,870	$	4,254
	Customer relationship intangible assets	3,447		1,014		2,433
		$	9,571	$	2,884	$	6,687
		Core deposit		Customer
		intangible		relationship
				intangible
		(dollars in thousands)
	As of December 31, 2014:
	Gross carrying amount	$	19,962	$	11,320
	Accumulated amortization	15,708		8,887
		$	4,254	$	2,433
	Estimated amortization expense on balance at December 31, 2014:
	2015	$	1,719	$	972
	2016	1,644		929
	2017	891		532
		$	4,254	$	2,433

Deposits

Deposits	12 Months Ended
	Dec. 31, 2014
Deposits
Deposits
	Note 8.  Deposits
	The composition of deposits is as follows:
		December 31,
		2014		2013
		(dollars in thousands)
	Demand deposits, non-interest-bearing	$	666,607	$	547,531
	Interest-bearing transaction deposits	67,774		61,384
	Savings deposits	210,673		206,587
	Money market deposits	1,459,723		1,471,265
	Time deposits	496,071		582,371
	Total	$	2,900,848	$	2,869,138
	The aggregate amount of time deposits with a minimum denomination of $100,000 was approximately $138.4 million and $163.7 million at December 31, 2014 and 2013, respectively.  The aggregate amount of time deposits with a minimum denomination that meet or exceed the FDIC insurance limit of $250,000 was approximately $24.4 million and $28.8 million at December 31, 2014 and 2013, respectively.  National deposits of $0.5 million were included in the balance of time deposits as of December 31, 2014 and 2013. The Company did not have any brokered deposits at December 31, 2014 or 2013.
	As of December 31, 2014, the scheduled maturities of time deposits, in thousands, are as follows:
	2015	$	309,598
	2016	95,118
	2017	61,161
	2018	18,934
	2019	11,250
	Thereafter	10
		$	496,071

Federal_Funds_Purchased_and_Se

Federal Funds Purchased and Securities Sold Under Agreements to Repurchase	12 Months Ended
	Dec. 31, 2014
Federal Funds Purchased and Securities Sold Under Agreements to Repurchase
Federal Funds Purchased and Securities Sold Under Agreements to Repurchase
	Note 9.  Federal Funds Purchased and Securities Sold Under Agreements to Repurchase
	Federal funds purchased are short-term borrowings that generally mature between one and ninety days. The Company had no federal funds purchased at December 31, 2014 and 2013; however, during 2014 the Company purchased federal funds to test operational availability to access funds if needed. Securities sold under agreements to repurchase, which are classified as secured borrowings, generally mature either daily or within one year from the transaction date. Securities sold under agreements to repurchase are reflected at the amount of cash received in connection with the transaction. The underlying securities are held by the Company’s safekeeping agent. The Company may be required to provide additional collateral based on the fair value of the underlying securities. The following table sets forth the distribution of securities sold under agreements to repurchase and weighted average interest rates:
		December 31,
		2014			2013
		(dollars in thousands)
	Balance	$	198,893		$	172,348
	Weighted average interest rate at end of period	0.14		%	0.13		%
	Maximum outstanding at any month end	$	198,893		$	172,348
	Average daily balance	$	148,452		$	137,777
	Weighted average interest rate during period (1)	0.12		%	0.14		%
	(1) The weighted average interest rate is computed by dividing total interest for the period by the average daily balance outstanding.

Shortterm_Borrowings

Short-term Borrowings	12 Months Ended
	Dec. 31, 2014
Short-term Borrowings
Short-term Borrowings
	Note 10.  Short-term Borrowings
	Short-term borrowings consist of advances which mature in less than one year from date of origination.  FHLB advances are collateralized by FHLB deposits, residential and commercial real estate loans and FHLB stock.  The Company had no short-term FHLB advances outstanding at December 31, 2014 and 2013; however, during 2014 the Company tested operational availability to access funds if needed.

Longterm_Debt

Long-term Debt	12 Months Ended
	Dec. 31, 2014
Long-term Debt
Long-term Debt
	Note 11.  Long-term Debt
	Long-term debt is summarized as follows:
		December 31,
		2014		2013
		(dollars in thousands)
	Notes payable, FHLB, ranging in maturity from five to ten years, collateralized by FHLB deposits, residential and commercial real estate loans and FHLB stock.	$	50,000	$	—
	As of December 31, 2014, funds borrowed from the FHLB, listed above, consisted of variable-rate notes maturing through September 2024, with interest rates ranging from 0.07% to 0.13%.  The weighted average rate on these long-term advances was 0.09% as of December 31, 2014.

Junior_Subordinated_Debt_Owed_

Junior Subordinated Debt Owed to Unconsolidated Trusts	12 Months Ended
	Dec. 31, 2014
Junior Subordinated Debt Owed to Unconsolidated Trusts
Junior Subordinated Debt Owed to Unconsolidated Trusts
	Note 12.  Junior Subordinated Debt Owed to Unconsolidated Trusts
	First Busey Corporation has established statutory trusts for the sole purpose of issuing trust preferred securities and related trust common securities.  The proceeds from such issuances were used by the trusts to purchase junior subordinated notes of the Company, which are the sole assets of each trust.  Concurrent with the issuance of the trust preferred securities, the Company issued guarantees for the benefit of the holders of the trust preferred securities.  The trust preferred securities are issues that qualify, and are treated by the Company, as Tier 1 regulatory capital.  The Company owns all of the common securities of each trust.  The trust preferred securities issued by each trust rank equally with the common securities in right of payment, except that if an event of default under the indenture governing the notes has occurred and is continuing, the preferred securities will rank senior to the common securities in right of payment.
	The table below summarizes the outstanding junior subordinated notes and the related trust preferred securities issued by each trust as of December 31, 2014:
		First Busey Statutory Trust II	First Busey Statutory Trust III	First Busey Statutory Trust IV
	Junior Subordinated Notes:
	Principal balance	$15,000,000	$10,000,000	$30,000,000
	Annual interest rate(1)	3-mo LIBOR + 2.65%	3-mo LIBOR + 1.75%	3-mo LIBOR + 1.55%
	Stated maturity date	June 17, 2034	June 15, 2035	June 15, 2036
	Trust Preferred Securities:
	Face value	$15,000,000	$10,000,000	$30,000,000
	Annual distribution rate(1)	3-mo LIBOR + 2.65%	3-mo LIBOR + 1.75%	3-mo LIBOR + 1.55%
	Issuance date	April 30, 2004	June 15, 2005	June 15, 2006
	Distribution dates(2)	Quarterly	Quarterly	Quarterly
	(1) First Busey Statutory Trust IV maintained a 5-year fixed coupon of 6.94% through June 10, 2011, subsequently converting to a floating 3-month LIBOR +1.55%.
	(2) All cash distributions are cumulative.
	The trust preferred securities are subject to mandatory redemption, in whole or in part, upon repayment of the junior subordinated notes at par value at the stated maturity date or upon redemption. Each trust’s ability to pay amounts due on the trust preferred securities is solely dependent upon the Company making payment on the related junior subordinated notes.  The Company’s obligations under the junior subordinated notes and other relevant trust agreements, in aggregate, constitute a full and unconditional guarantee by the Company of each trust’s obligations under the trust preferred securities issued by each trust.  The Company has the right to defer payment of interest on the notes, in which case the distributions on the trust preferred securities will also be deferred, for up to five years, but not beyond the stated maturity date in the table above. The Company does not expect to exercise this right.
	In March 2005, the Federal Reserve issued a final rule allowing bank holding companies to continue to include qualifying trust preferred securities in their Tier 1 Capital for regulatory capital purposes, subject to a 25% limitation to all core (Tier 1) capital elements, net of goodwill and other intangible assets less any associated deferred tax liability.  The final rule provided a five-year transition period, which was extended to March 31, 2011, for applications of the aforementioned quantitative limitation.  As of December 31, 2014, 100% of the trust preferred securities noted in the table above qualified as Tier 1 capital under the final rule adopted in March 2005.
	The Dodd-Frank Act required the Board of Governors of the Federal Reserve System to establish minimum capital levels for bank holding companies on a consolidated basis that are as stringent as those required for insured depository institutions.  The components of Tier 1 capital will be restricted to capital instruments that are currently considered to be Tier 1 capital for insured depository institutions.  As a result, the proceeds of trust preferred securities will be excluded from Tier 1 capital unless such securities were issued prior to May 19, 2010 by bank holding companies with less than $15 billion of assets. As the Company has assets of less than $15 billion, it will be able to maintain its trust preferred proceeds as Tier 1 capital but it will have to comply with new capital mandates in other respects, and it will not be able to raise Tier 1 capital in the future through the issuance of trust preferred securities.

Capital

Capital	12 Months Ended
	Dec. 31, 2014
Capital
Capital
	Note 13.  Capital
	Issuance of Preferred Stock Under the Small Business Lending Fund
	On August 25, 2011, the Company entered into the Purchase Agreement with the Treasury, pursuant to which the Company issued and sold to the Treasury 72,664 shares of its Series C Preferred Stock, having a liquidation preference of $1,000 per share, for aggregate proceeds of $72,664,000 (which were used to partially finance the Company’s redemption of Series T Preferred Stock as described below).  The SBLF is a Treasury lending program that encourages qualified community banks to partner with small businesses and entrepreneurs to create jobs and promote economic development in local communities.
	The Series C Preferred Stock qualifies as Tier 1 capital for the Company. Non-cumulative dividends are payable quarterly on the Series C Preferred Stock, which began October 1, 2011. The dividend rate was calculated as a percentage of the aggregate “Liquidation Amount” of the outstanding Series C Preferred Stock and was based on changes in the level of “Qualified Small Business Lending” or “QSBL” (as such terms are defined in the Purchase Agreement) by the Bank. Based upon the lack of increase in the Bank’s level of QSBL over the baseline level calculated under the terms of the Purchase Agreement, the dividend rate for the initial dividend period, which was from the date of issuance through September 30, 2011, was set at 5%. For the 2nd through 10th calendar quarters, which ended December 31, 2013, the annual dividend rate also remained at 5%. For the 11th calendar quarter through 4.5 years after issuance, the dividend rate will be fixed at between 1% and 7% based upon the level of QSBL as compared to the baseline. In the third quarter of 2013, the Company had meaningful progress in commercial loan growth which led to the successful attainment of targets under the SBLF program.  The achievement of this important milestone under SBLF yielded the lowest possible dividend rate in 2014 of 1%.  After 4.5 years from issuance, which will be in the first quarter of 2016, the dividend rate will increase to 9%.
	The Series C Preferred Stock is non-voting, except in limited circumstances.  The Company may redeem the shares of Series C Preferred Stock, in whole or in part, at any time at a redemption price equal to the sum of the Liquidation Amount per share and the per share amount of any unpaid dividends for the then-current period, subject to any required prior approval by the Company’s primary federal banking regulator.
	Redemption of Series T Preferred Stock
	The Company’s Series T Preferred Stock, was issued to the Treasury on March 6, 2009 in connection with the Company’s participation in the TARP CPP. On August 25, 2011, the Company entered into and consummated the transactions contemplated by the Repurchase Document with the Treasury.  Under the Repurchase Document, the Company redeemed from the Treasury, in part using the proceeds from the issuance of the Series C Preferred Stock, all 100,000 outstanding shares of its Series T Preferred Stock, for a redemption price of approximately $100.1 million, including accrued but unpaid dividends to the date of redemption.
	In connection with the Company’s participation in the CPP, the Company also issued to Treasury a warrant to purchase 1,147,666 shares of the Company’s common stock.  Subsequent to the date of the Company’s participation in the CPP, it raised additional capital through a public offering of common stock and, as a result of that offering, the number of shares of common stock subject to the warrant were reduced by 50% to 573,833.  On November 23, 2011 the Treasury completed an auction to sell its warrant in a private transaction. At December 31, 2014, this warrant to purchase 573,833 shares of the Company’s common stock remained outstanding.
	Regulatory Capital
	The ability of the Company to pay cash dividends to its stockholders and to service its debt historically was dependent on the receipt of cash dividends from its subsidiaries.  However, Busey Bank sustained significant losses during 2008 and 2009 resulting in pressure on its capital, which was relieved through injections of capital from the Company.  State chartered banks have certain statutory and regulatory restrictions on the amount of cash dividends they may pay.  Due to the significant losses in the past and the Company’s desire to maintain a strong capital position at Busey Bank, no dividends have been paid from Busey Bank since 2009.  Until such time as retained earnings have been restored, Busey Bank will not be permitted to pay dividends, and we will need to request permission from Busey Bank’s primary regulator to distribute any capital out of Busey Bank.  On January 22, 2013, with the approval of its primary regulator, Busey Bank transferred $50.0 million to the Company, representing a return of capital and associated surplus as a result of an amendment to Busey Bank’s charter.  Further, on October 22, 2014, with the approval of its primary regulator, Busey Bank transferred $60.0 million to the Company, representing a return of capital and associated surplus as a result of a further amendment to Busey Bank’s charter.
	The Company and Busey Bank are subject to regulatory capital requirements administered by federal and state banking agencies that involve the quantitative measure of their assets, liabilities, and certain off-balance-sheet items, as calculated under regulatory accounting practices.  Quantitative measures established by regulations to ensure capital adequacy require the Company and Busey Bank to maintain minimum amounts and ratios (set forth in the table below) of total and Tier 1 capital (as defined in the regulations) to risk-weighted assets (as defined in the regulations), and, for the Bank, Tier 1 capital (as defined in the regulations) to average assets (as defined in the regulations).  Failure to meet minimum capital requirements may cause regulatory bodies to initiate certain discretionary and/or mandatory actions that, if undertaken, may have a direct material effect on our financial statements.  The Company, as a financial holding company, is required to be “well capitalized” in the two capital categories based on risk-weighted assets, as shown in the table below.  As of December 31, 2014, the Company and Busey Bank met all capital adequacy requirements to which they were subject, including the guidelines to be considered “well capitalized.”
						Minimum				Minimum
						Capital				To Be Well
		Actual				Requirement				Capitalized
		Amount		Ratio		Amount		Ratio		Amount		Ratio
		(dollars in thousands)
	As of December 31, 2014:
	Total Capital (to Risk Weighted Assets)
	Consolidated	$	488,908	18.66	%	$	209,554	8.00	%	$	261,942	10.00	%
	Busey Bank	$	388,479	14.94	%	$	207,991	8.00	%	$	259,988	10.00	%
	Tier 1 Capital (to Risk Weighted Assets)
	Consolidated	$	455,354	17.38	%	$	104,777	4.00	%	$	157,166	6.00	%
	Busey Bank	$	355,166	13.66	%	$	103,996	4.00	%	$	155,993	6.00	%
	Tier 1 Capital (to Average Assets)
	Consolidated	$	455,354	12.79	%	$	142,401	4.00	%	N/A		N/A
	Busey Bank	$	355,166	10.10	%	$	140,677	4.00	%	$	175,846	5.00	%
	As of December 31, 2013:
	Total Capital (to Risk Weighted Assets)
	Consolidated	$	449,407	18.21	%	$	197,422	8.00	%	$	246,777	10.00	%
	Busey Bank	$	396,248	16.17	%	$	196,002	8.00	%	$	245,002	10.00	%
	Tier 1 Capital (to Risk Weighted Assets)
	Consolidated	$	417,564	16.92	%	$	98,711	4.00	%	$	148,067	6.00	%
	Busey Bank	$	364,625	14.88	%	$	98,001	4.00	%	$	147,001	6.00	%
	Tier 1 Capital (to Average Assets)
	Consolidated	$	417,564	12.02	%	$	138,896	4.00	%	N/A		N/A
	Busey Bank	$	364,625	10.66	%	$	136,818	4.00	%	$	171,023	5.00	%
	On July 21, 2010, President Obama signed the Dodd-Frank Act into law, which required the Board of Governors of the Federal Reserve System to establish minimum capital levels for bank holding companies on a consolidated basis that are as stringent as those required for insured depository institutions.  The components of Tier 1 capital are restricted to capital instruments that are currently considered to be Tier 1 capital for insured depository institutions.  As a result, the proceeds of trust preferred securities are excluded from Tier 1 capital unless such securities were issued prior to May 19, 2010 by bank holding companies with less than $15 billion of assets. As the Company has assets of less than $15 billion, it will be able to maintain its trust preferred proceeds as Tier 1 capital but it will have to comply with new capital mandates in other respects, and it will not be able to raise Tier 1 capital through the issuance of trust preferred securities.
	In July 2013, the U.S. federal banking authorities approved the implementation of the Basel III Rules.  The Basel III Rules are applicable to all U.S. banks that are subject to minimum capital requirements, as well as to bank and savings and loan holding companies other than “small bank holding companies” (generally bank holding companies with consolidated assets of less than 1 billion).  The Basel III Rules not only increased most of the required minimum regulatory capital ratios, but they also introduced a new Common Equity Tier 1 Capital ratio and the concept of a capital conservation buffer.  The Basel III Rules also expanded the definition of capital as in effect currently by establishing criteria that instruments must meet to be considered Additional Tier 1 Capital (Tier 1 Capital in addition to Common Equity) and Tier 2 Capital.  A number of instruments that now generally qualify as Tier 1 Capital will not qualify, or their qualifications will change, when the Basel III Rules are fully implemented.
	The Basel III Rules also permit banking organizations with less than $15.0 billion in assets to retain, through a one-time election, the existing treatment for accumulated other comprehensive income, which currently does not affect regulatory capital.  First Busey and the Bank expect to make this election in the first quarter of 2015 to avoid variations in the level of their capital depending on fluctuations in the fair value of their securities portfolio.  The Basel III Rules have maintained the general structure of the current prompt corrective action framework, while incorporating the increased requirements. The prompt corrective action guidelines were also revised to add the Common Equity Tier 1 Capital ratio.  In order to be a “well-capitalized” depository institution under the new regime, a bank and holding company must maintain a Common Equity Tier 1 Capital ratio of 6.5% or more; a Tier 1 Capital ratio of 8% or more; a Total Capital ratio of 10% or more; and a leverage ratio of 5% or more.  Generally, financial institutions became subject to the new Basel III Rules on January 1, 2015, with phase-in periods for many of the changes.  Management believes that, as of December 31, 2014, the Company and the Bank would meet all capital adequacy requirements under the Basel III Rules on a fully phased-in basis as if such requirements had been in effect.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Taxes
Income Taxes
	Note 14.  Income Taxes
	The components of income taxes consist of:
		Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Current	$	4,830		$	4,020		$	1,926
	Deferred	12,704			10,091			8,571
	Total income tax expense	$	17,534		$	14,111		$	10,497
	A reconciliation of federal and state income taxes at statutory rates to the income taxes included in the statements of income is as follows:
		Years Ended December 31,
		2014		2013		2012
		% of		% of		% of
		Pretax		Pretax		Pretax
		Income		Income		Loss
	Income tax at statutory rate	35.0	%	35.0	%	35.0	%
	Effect of:
	Tax-exempt interest, net	(2.6	)%	(3.5	)%	(4.5	)%
	State income taxes, net	5.7	%	4.5	%	3.5	%
	Income on bank owned life insurance	(1.0	)%	(0.9	)%	(1.8	)%
	Other, net	(2.2	)%	(2.2	)%	(0.3	)%
		34.9	%	32.9	%	31.9	%
	Net deferred taxes at December 31, 2014 and 2013 in the accompanying Consolidated Balance Sheets, include the following amounts of deferred tax assets and liabilities:
		2014			2013
		(dollars in thousands)
	Deferred tax assets:
	Allowance for loan losses	$	18,904		$	19,416
	Stock-based compensation	1,472			1,319
	Loan adjustments	94			108
	Deferred compensation	2,057			2,015
	Accrued vacation	527			545
	Employee costs	656			1,264
	Other	2,498			1,780
		$	26,208		$	26,447
	Deferred tax liabilities:
	Investment securities:
	Unrealized gains on securities available for sale	$	(3,884	)	$	(3,119	)
	Other	(1,997		)	(2,450		)
	Basis in premises and equipment	(2,012		)	(2,590		)
	Mortgage servicing assets	(1,549		)	(2,097		)
	Basis in core deposit and customer intangible assets	(2,669		)	(3,908		)
	Deferred loan origination costs	(257		)	(20		)
		$	(12,368	)	$	(14,184	)
	Net operating loss carryforward, net of valuation allowance	8,333			23,379
	Net deferred tax assets	$	22,173		$	35,642
	At December 31, 2014, the Company had Illinois net operating loss carryforwards of $8.3 million, or approximately $114.0 million pre-tax.  At December 31, 2013, the Company had federal and Illinois net operating loss carryforwards of $23.4 million, or approximately $33.0 million in federal pre-tax and $171.0 million in Illinois pre-tax.  These net operating loss carryforwards will expire in 2030.
	At December 31, 2014, the Company also had Indiana and Florida net operating loss carryforwards of $1.0 million, which will begin to expire in 2030. Due to the uncertainty as to whether the Company will be able to realize the Indiana and Florida carryforwards, the Company has a full valuation allowance of $1.0 million related to these net operating loss carryforwards.  At December 31, 2013, the Company had Indiana and Florida net operating loss carryforwards of $1.5 million with a full valuation allowance.
	Management believes that it is more likely than not that the other deferred tax assets included in the accompanying Consolidated Balance Sheets will be fully realized. The Company has determined that no valuation allowance is required for any other deferred tax assets as of December 31, 2014 and 2013, although there is no guarantee that those assets will be recognizable in future periods.

Employee_Benefit_Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2014
Employee Benefit Plans
Employee Benefit Plans
	Note 15.  Employee Benefit Plans
	Employees’ Stock Ownership Plan
	Prior to 2014, the First Busey Corporation Employees’ Stock Ownership Plan (“ESOP”) was available to all full-time employees who met certain age and length of service requirements.  Effective for 2014, the ESOP was frozen, all shares were fully vested and there will be no new contributions under the ESOP.  Dividends on allocated shares of common stock are distributed directly to the participants.  All shares held by the ESOP, which were acquired prior to the issuance of FASB ASC Topic 718-40, “Employee Stock Ownership Plans” (ASC 718-40), are included in the computation of average common shares and common share equivalents. This accounting treatment is grandfathered under ASC 718-40 for shares purchased prior to December 31, 1992.
	All shares held in the ESOP which were acquired prior to December 31, 1992 were allocated as of December 31, 2006.  The number of shares and associated fair values were 479,755 worth $3.1 million and 543,471 worth $3.2 million at December 31, 2014 and 2013, respectively.
	Shares held in the ESOP which were acquired after December 31, 1992 and associated fair values were 171,988 worth $1.1 million and 192,171 worth $1.1 million at December 31, 2014 and 2013, respectively.
	Profit Sharing Plan
	All full-time employees who meet certain age and service requirements are eligible to participate in the Company’s profit-sharing plan. The contributions, if any, are determined solely by the boards of directors of the Company and its subsidiaries, and in no case may the annual contributions be greater than the amounts deductible for federal income tax purposes for that year.
	The rights of the participants vest ratably over a five-year period, except for the 401(k) match portion, which vests immediately. Expenses related to the employee benefit plans are included in the statements of income as follows:
		Years Ended December 31,
		2014		2013		2012
		(dollars in thousands)
	Employee benefits	$	2,636	$	2,975	$	3,024
	Interest on employee stock ownership plan debt	—		—		5
	Total employer contributions	$	2,636	$	2,975	$	3,029
	The Company sponsors deferred compensation plans for executive officers for deferral of compensation. While current participants in the deferred compensation plan are permitted to continue participating in the plan, it is no longer open to new participants.  The deferred compensation expense reported was $0.3 million for the year ended December 31, 2014 and $0.2 million for the years ended December 31, 2013 and 2012. The deferred compensation liability was $5.1 million at December 31, 2014, $4.8 million at December 31, 2013, and $4.5 million at December 31, 2012.

Stock_Incentive_Plans

Stock Incentive Plans	12 Months Ended
	Dec. 31, 2014
Stock Incentive Plans
Stock Incentive Plans
	Note 16.  Stock Incentive Plans
	Overview
	During the second quarter of 2010, the Company adopted the 2010 Equity Plan, which was approved at the annual stockholders meeting on May 19, 2010. The Company no longer makes any additional grants under prior plans. The prior plans include:  the First Busey Corporation 1993 Restricted Stock Award Plan, the First Busey Corporation 1999 Stock Option Plan, the Main Street Trust, Inc. 2000 Stock Incentive Plan, and the First Busey Corporation 2004 Stock Option Plan.
	Subject to permitted adjustments for certain corporate transactions, the maximum number of shares that may be delivered to participants, or their beneficiaries, under the 2010 Equity Plan is 4,000,000 shares of First Busey common stock. To the extent that any shares of stock covered by an award (including non-vested stock awards) under the 2010 Equity Plan, or the prior plans, are not delivered for any reason, including because the award is forfeited, canceled, settled in cash or shares are withheld to satisfy tax withholding requirements, such shares will not be deemed to have been delivered for purposes of determining the maximum number of shares of stock available for delivery and will again become available for usage under the 2010 Equity Plan. If any option granted under the 2010 Equity Plan is exercised by tendering shares of stock, only the number of shares of stock issued net of the shares of stock tendered shall be counted for purposes of these limitations.
	The 2010 Equity Plan’s effective date was May 19, 2010. The 2010 Equity Plan will continue in effect until terminated by the board of directors; provided that no awards may be granted under the 2010 Equity Plan after the ten-year anniversary of the effective date. Any awards that are outstanding after the tenth anniversary of the effective date will remain subject to the terms of the 2010 Equity Plan.
	The following additional limits apply to awards under the 2010 Equity Plan:
		·		the maximum number of shares of stock that may be covered by options that are intended to be “performance-based compensation” which are granted to any one participant during any calendar year is 400,000 shares;
		·		the maximum number of shares of stock that may be covered by stock awards that are intended to be “performance-based compensation” which are granted to any one participant during any calendar year is 200,000 shares; and
		·		the maximum dollar amount of cash incentive awards or cash-settled stock awards intended to be “performance-based compensation” payable to any one participant with respect to any calendar year is $1,000,000.
	The Company grants share-based compensation awards to its employees and members of its board of directors as provided for under the Company’s 2010 Equity Incentive Plan. The Company currently grants share-based compensation in the form of restricted stock units (“RSUs”) and deferred stock units (“DSUs”).  The Company also has outstanding stock options granted prior to 2011.  Under the terms of the Company’s 2010 Equity Incentive Plan, the Company is allowed, but not required, to source stock option exercises and grants of RSUs and DSUs from its inventory of treasury stock.
	As of December 31, 2014, the Company held 1,426,323 shares in treasury, with 895,655 additional shares authorized for repurchase under its stock repurchase plan.  On February 3, 2015, First Busey announced that its board of directors approved a repurchase plan under which the Company is authorized to repurchase, from time to time as the Company deems appropriate, up to an aggregate of two million shares of its common stock.  The repurchase plan has no expiration date and replaced the repurchase plan that was originally approved in 2008.
	The Company’s 2010 Equity Incentive Plan is designed to encourage ownership of its common stock by its employees and directors, to provide additional incentive for them to promote the success of its business, and to attract and retain talented personnel. All of the Company’s employees and directors, and those of its subsidiaries, are eligible to receive awards under the plan.
	Stock Option Plan
	A summary of the status of the Company’s stock option awards for the years ended December 31, 2014, 2013, and 2012, and the changes during the years ended on those dates is as follows:
			2014					2013					2012
					Weighted-					Weighted-					Weighted-
					Average					Average					Average
					Exercise					Exercise					Exercise
			Shares		Price			Shares		Price			Shares		Price
	Outstanding at beginning of year		696,379		$	17.22		857,468		$	17.01		1,017,922		$	16.23
	Granted		—		—			—		—			—		—
	Exercised		—		—			—		—			—		—
	Forfeited		(186,249	)	19.67			(161,089	)	16.1			(160,454	)	12.07
	Outstanding at end of year		510,130		$	16.33		696,379		$	17.22		857,468		$	17.01
	Exercisable at end of year		510,130		$	16.33		696,379		$	17.22		857,468		$	17.01
	The following table summarizes information about stock options outstanding at December 31, 2014:
														Options
				Options Outstanding										Exercisable
									Weighted-
						Weighted-			Average
	Range of					Average			Remaining
	Exercise					Exercise			Contractual		Intrinsic					Intrinsic
	Prices			Number		Price			Life		Value			Number		Value
	$	4.49-7.53		105,000		$	6.01		5.00					105,000
	17.12-19.55			405,130		19.00			0.86					405,130
				510,130		$	16.33		1.71		$	106		510,130		$	106
	The Company did not record any stock option compensation expense during 2014, 2013 or 2012.  As of December 31, 2014, the Company has no unrecognized stock option expense.
	Restricted Stock Unit Plan
	The Company grants RSUs to members of management periodically throughout the year.  Each RSU is equivalent to one share of the Company’s common stock. These units have a requisite service period ranging from one to five years. In addition, all recipients earn quarterly dividend equivalents on their respective units. These dividend equivalents are not paid out during the vesting period, but instead entitle the recipients to additional units. Therefore, dividends earned each quarter compound based upon the updated unit balances.  Upon vesting/delivery, shares are expected (though not required) to be issued from treasury.
	A summary of the changes in the Company’s RSUs for the years ended December 31, 2014, 2013 and 2012 is as follows:
			2014					2013					2012
					Weighted-					Weighted-					Weighted-
					Average					Average					Average
					Grant Date					Grant Date					Grant Date
			Shares		Fair Value			Shares		Fair Value			Shares		Fair Value
	Outstanding at beginning of year		919,928		$	4.97		736,412		$	4.92		455,352		$	4.98
	Reclass to DSUs		(4,960	)	5.04			—		—			—		—
	Granted		304,277		5.84			351,452		5.02			266,258		4.83
	Dividend equivalents earned		35,166		5.62			17,211		4.86			32,704		4.79
	Vested		(26,432	)	4.82			(156,795	)	4.84			(9,925	)	4.19
	Forfeited		(44,109	)	4.73			(28,352	)	5.14			(7,977	)	5.15
	Outstanding at end of year		1,183,870		$	5.22		919,928		$	4.97		736,412		$	4.92
	The Company issued 18,618 and 111,012 treasury shares in conjunction with the vesting of RSUs in 2014 and 2013, respectively.  The difference between the number of shares issued and the number of vested units is due to shares issued under a net share settlement option.
	On June 23, 2014, under the terms of the 2010 Equity Incentive Plan, the Company granted 304,277 RSUs to members of management.  As the stock price on the grant date of June 23, 2014 was $5.84, total compensation cost to be recognized is $1.8 million.  This cost will be recognized over a period of two to five years.  Subsequent to each requisite service period, the awards will vest 100%.
	A listing of RSUs granted in 2013 and 2012 under the terms of the 2010 Equity Incentive Plan can be found in the Company’s Annual Reports on Form 10-K for the years ended December 31, 2013 and 2012.
	Deferred Stock Unit Plan
	The Company annually grants share-based awards in the form of DSUs, which are RSUs with a deferred settlement date, to its board of directors. Each DSU is equivalent to one share of the Company’s common stock. The DSUs vest over a twelve-month period following the grant date or on the next annual shareholder’s meeting, whichever is earlier. These units generally are subject to the same terms as RSUs under the Company’s 2010 Equity Incentive Plan, except that, following vesting, settlement occurs within 30 days following the earlier of separation from the board or a change in control of the Company. Subsequent to vesting and prior to delivery, these units will continue to earn dividend equivalents.
	A summary of the changes in the Company’s DSUs for the years ended December 31, 2014, 2013 and 2012 is as follows:
			2014					2013					2012
					Weighted-					Weighted-					Weighted-
					Average					Average					Average
					Grant Date					Grant Date					Grant Date
			Shares		Fair Value			Shares		Fair Value			Shares		Fair Value
Non-vested at beginning of year		29,054		$	5.05		32,991		$	4.77		22,771		$	5.23
Reclass from RSUs		4,960		5.04			—		—			—		—
Granted		49,699		5.84			28,800		5.04			31,897		4.77
Dividend equivalents earned		4,042		5.63			1,636		5.03			2,252		4.76
Vested		(32,011	)	5.1			(34,373	)	4.77			(23,929	)	5.21
Forfeited		—		—			—		—			—		—
Non-vested at end of year		55,745		$	5.77		29,054		$	5.05		32,991		$	4.77
Outstanding at end of year		146,057		$	5.34		87,356		$	5.06		56,920		$	4.96
On June 23, 2014, under the terms of the 2010 Equity Incentive Plan, the Company granted 36,000 DSUs to directors.  As the stock price on the grant date of June 23, 2014 was $5.84, total compensation cost to be recognized is $0.2 million. This cost will be recognized over the requisite service period of one year from the date of grant or the next annual shareholders’ meeting; whichever is earlier. The Company also granted 13,699 DSUs to the Chairman of the board.  As the stock price on the grant date of June 23, 2014 was $5.84, total compensation cost to be recognized is $0.1 million. This cost will be recognized over the requisite service period of five years.  Subsequent to the requisite service period, the awards will vest 100%.
A listing of DSUs granted in 2013 and 2012 under the terms of the 2010 Equity Incentive Plan can be found in the Company’s Annual Reports on Form 10-K for the years ended December 31, 2013 and 2012.
The Company recognized $1.2 million, $1.1 million and $1.0 million of compensation expense related to both non-vested RSUs and DSUs for the years ended December 31, 2014, 2013 and 2012, respectively. As of December 31, 2014, there was $3.6 million of total unrecognized compensation cost related to these non-vested stock awards. This cost is expected to be recognized over a period of 3.6 years.

Transactions_with_Directors_an

Transactions with Directors and Executive Officers	12 Months Ended
	Dec. 31, 2014
Transactions with Directors and Executive Officers
Transactions with Directors and Executive Officers
	Note 17.  Transactions with Directors and Executive Officers
	The Company has had, and may be expected to have in the future, banking transactions in the ordinary course of business with directors, executive officers, their immediate families and affiliated companies in which they have 10% or more beneficial ownership (commonly referred to as related parties), on the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with others.
	The following is an analysis of the changes in loans, in thousands, to related parties during the year ended December 31, 2014:
	Balance at beginning of year	$	30,105
	Addition due to change in relationship	8,393
	Deletion due to change in relationship	(40		)
	New loans/ advances	50,576
	Repayments	(51,584		)
	Balance at end of year	$	37,450
	Total unused commitments to directors and executive officers were $22.6 million at December 31, 2014.

Commitments_Contingencies_and_

Commitments, Contingencies and Credit Risk	12 Months Ended
	Dec. 31, 2014
Commitments, Contingencies and Credit Risk
Commitments, Contingencies and Credit Risk
	Note 18.  Commitments, Contingencies and Credit Risk
	Legal Matters
	The Company is a party to legal actions which arise in the normal course of its business activities.  In the opinion of management, the ultimate resolution of these matters is not expected to have a material effect on the financial position or the results of operations of the Company.
	Credit Commitments and Contingencies
	The Company is a party to credit-related financial instruments with off-balance-sheet risk in the normal course of business to meet the financing needs of its customers.  These financial instruments include commitments to extend credit and standby letters of credit.  Those instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the Consolidated Balance Sheets.
	The Company’s exposure to credit loss is represented by the contractual amount of those commitments.  The Company uses the same credit policies in making commitments and conditional obligations as it does for on-balance-sheet instruments.  A summary of the contractual amount of the Company’s exposure to off-balance-sheet risk relating to the Company’s commitments to extend credit and standby letters of credit follows:
		December 31,
		2014		2013
		(dollars in thousands)
	Financial instruments whose contract amounts represent credit risk:
	Commitments to extend credit	$	561,439	$	527,614
	Standby letters of credit	20,466		10,155
	Commitments to extend credit are agreements to lend to a customer as long as no condition established in the contract has been violated.  These commitments are generally at variable interest rates and generally have fixed expiration dates or other termination clauses and may require payment of a fee.  The commitments for equity lines of credit may expire without being drawn upon.  Therefore, the total commitment amounts do not necessarily represent future cash requirements.  The amount of collateral obtained, if it is deemed necessary by the Company upon extension of credit, is based on management’s credit evaluation of the customer.
	Standby letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer’s obligation to a third party.  Those guarantees are primarily issued to support public and private borrowing arrangements, including bond financing and similar transactions and primarily have terms of one year or less.  The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers.  The Company holds collateral, which may include accounts receivable, inventory, property and equipment, and income producing properties, supporting those commitments if deemed necessary.  In the event the customer does not perform in accordance with the terms of the agreement with the third party, the Company would be required to fund the commitment.  The maximum potential amount of future payments the Company could be required to make is represented by the contractual amount shown in the summary above.  If the commitment is funded, the Company would be entitled to seek recovery from the customer. As of December 31, 2014 and 2013, no amounts were recorded as liabilities for the Bank’s potential obligations under these guarantees.
	Lease Commitments
	At December 31, 2014, the Company was obligated under noncancelable operating leases for office space and other commitments. Rent expense under operating leases, included in net occupancy and equipment expense, was $1.5 million, $1.6 million, and $2.5 million for the years ended December 31, 2014, 2013 and 2012, respectively.
	The projected minimum rental payments under the terms of the leases at December 31, 2014 in thousands, are as follows:
	2015	$	941
	2016	219
	2017	111
	2018	102
	2019	70
		$	1,443

Derivative_Financial_Instrumen

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2014
Derivative Financial Instruments
Derivative Financial Instruments
	Note 19: Derivative Financial Instruments
	Starting in the first quarter of 2014, the Company began entering into loan agreements that settled in non-U.S. dollar denominations.  The foreign loan balance, gross, translated into U.S. dollars as of December 31, 2014 was $1.8 million.
	Foreign Currency Derivatives. The Company enters into foreign currency forward contracts that are not designated as hedging instruments to mitigate the economic effect of fluctuations in foreign currency exchange rates on certain non-U.S. dollar denominated loans.  Because the foreign currency forward contracts do not meet hedge accounting requirements, gains and losses due to changes in their fair values are recognized in other income.
	The notional amount and fair values of open foreign currency forward contracts were as follows:
		December 31, 2014		December 31, 2013
		(dollars in thousands)
	Forward contracts — foreign exchange:
	Notional amount	$	1,781	$	—
	Other assets — estimated fair value	15		—
	The amount of gains and losses relating to foreign currency forward contracts included in other income for the year ended December 31, 2014 was insignificant.
	Foreign currency forward contracts involve the risk of dealing with counterparties and their ability to meet contractual terms.  We believe the risk of incurring losses due to nonperformance by our counterparties is manageable.
	As of December 31, 2014, the Company had no other interest rate futures, forwards, swaps or option contracts, or other financial instruments with similar characteristics with the exception of rate lock commitments on mortgage loans to be held for sale, which netted to an insignificant amount.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2014
Fair Value Measurements
Fair Value Measurements
	Note 20 - Fair Value Measurements
	The fair value of an asset or liability is the price that would be received by selling that asset or paid in transferring that liability in an orderly transaction occurring in the principal market (or most advantageous market in the absence of a principal market) for such asset or liability. In estimating fair value, the Company utilizes valuation techniques that are consistent with the market approach, the income approach and/or the cost approach. Such valuation techniques are consistently applied. Inputs to valuation techniques include the assumptions that market participants would use in pricing an asset or liability. FASB ASC Topic 820 establishes a fair value hierarchy for valuation inputs that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The fair value hierarchy is as follows:
	Level 1 Inputs - Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.
	Level 2 Inputs - Inputs other than quoted prices included in level 1 that are observable for the asset or liability, either directly or indirectly. These might include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (such as interest rates, volatilities, prepayment speeds, credit risks, etc.) or inputs that are derived principally from or corroborated by market data by correlation or other means.
	Level 3 Inputs - Unobservable inputs for determining the fair values of assets or liabilities that reflect the Company’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities.
	A description of the valuation methodologies used for instruments measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy, is set forth below. These valuation methodologies were applied to those Company assets and liabilities that are carried at fair value.
	There were no transfers between levels during the quarter or year ended December 31, 2014.
	In general, fair value is based upon quoted market prices, when available. If such quoted market prices are not available, fair values are measured utilizing independent valuation techniques of identical or similar securities for which significant assumptions are derived primarily from or corroborated by observable data. Valuation adjustments may be made to ensure that financial instruments are recorded at fair value. These adjustments may include amounts to reflect, among other things, counterparty credit quality and the company’s creditworthiness as well as unobservable parameters. Any such valuation adjustments are applied consistently over time. The Company’s valuation methodologies may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. While management believes the Company’s valuation methodologies are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date.  Furthermore, the reported fair value amounts have not been comprehensively revalued since the presentation dates and, therefore, estimates of fair value after the balance sheet date may differ significantly from the amounts presented herein.
	Securities Available for Sale. Securities classified as available for sale are reported at fair value utilizing level 1 and level 2 measurements. For mutual funds and other equity securities, unadjusted quoted prices in active markets for identical assets are utilized to determine fair value at the measurement date and have been classified as level 1 in the ASC 820 fair value hierarchy.  For all other securities, the Company obtains fair value measurements from an independent pricing service. The independent pricing service evaluations are based on market data.  The independent pricing service utilizes evaluated pricing models that vary by asset class and incorporate available trade, bid and other market information.  Because many fixed income securities do not trade on a daily basis, the independent pricing service evaluated pricing applications apply available information as applicable through processes such as benchmark curves, benchmarking of like securities, sector groupings, and matrix pricing, to prepare evaluations.  In addition, the independent pricing service uses model processes, such as the Option Adjusted Spread model, to assess interest rate impact and develop prepayment scenarios.  The models and processes take into account market convention.  For each asset class, a team of evaluators gathers information from market sources and integrates relevant credit information, perceived market movements and sector news into the evaluated pricing applications and models.
	The market inputs that the independent pricing service normally seeks for evaluations of securities, listed in approximate order of priority, include: benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers and reference data including market research publications.  The independent pricing service also monitors market indicators, industry and economic events.  Information of this nature is a trigger to acquire further market data.  For certain security types, additional inputs may be used or some of the market inputs may not be applicable.  Evaluators may prioritize inputs differently on any given day for any security based on market conditions, and not all inputs listed are available for use in the evaluation process for each security evaluation on a given day.  Because the data utilized was observable, the securities have been classified as level 2 in the ASC 820 fair value hierarchy.
	Derivative Assets and Derivative Liabilities. Derivative assets and derivative liabilities are reported at fair value utilizing level 2 measurements.  Derivative instruments with positive fair values are reported as an asset and derivative instruments with negative fair value are reported as liabilities.  The fair value of derivative assets and liabilities is determined based on prices obtained from a third party.  Values of derivative assets and liabilities are primarily based on observable inputs and are classified as level 2 in the ASC 820 fair value hierarchy.
	The following table summarizes financial assets and financial liabilities measured at fair value on a recurring basis as of December 31, 2014 and 2013, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value:
		Level 1		Level 2			Level 3		Total
		Inputs		Inputs			Inputs		Fair Value
		(dollars in thousands)
	December 31, 2014
	Securities available for sale
	U.S. Treasury securities	$	—	$	50,606		$	—	$	50,606
	Obligations of U.S. government corporations and agencies	—		167,010			—		167,010
	Obligations of states and political subdivisions	—		220,161			—		220,161
	Residential mortgage-backed securities	—		235,636			—		235,636
	Corporate debt securities	—		79,307			—		79,307
	Mutual funds and other equity securities	6,345		—			—		6,345
	Derivative assets
	Foreign currency forward contracts	—		15			—		15
	December 31, 2013
	Securities available for sale
	U.S. Treasury securities	$	—	$	102,640		$	—	$	102,640
	Obligations of U.S. government corporations and agencies	—		257,411			—		257,411
	Obligations of states and political subdivisions	—		272,152			—		272,152
	Residential mortgage-backed Securities	—		177,735			—		177,735
	Corporate debt securities	—		25,506			—		25,506
	Mutual funds and other equity securities	5,866		—			—		5,866
	Certain financial assets and financial liabilities are measured at fair value on a non-recurring basis; that is, the instruments are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment).
	Impaired Loans. The Company does not record loans at fair value on a recurring basis. However, periodically, a loan is considered impaired and is reported at the fair value of the underlying collateral, less estimated costs to sell, if repayment is expected solely from the collateral.  Impaired loans measured at fair value typically consist of loans on non-accrual status and restructured loans in compliance with modified terms.  Collateral values are estimated using a combination of observable inputs, including recent appraisals, and unobservable inputs based on customized discounting criteria. Due to the significance of the unobservable inputs, all impaired loan fair values have been classified as level 3 in the ASC 820 fair value hierarchy.
	OREO.  Non-financial assets and non-financial liabilities measured at fair value include OREO (upon initial recognition or subsequent impairment). OREO properties are measured using a combination of observable inputs, including recent appraisals, and unobservable inputs based on customized discounting criteria. Due to the significance of the unobservable inputs, all OREO fair values have been classified as level 3 in the ASC 820 fair value hierarchy.
	The following table summarizes assets and liabilities measured at fair value on a non-recurring basis as of December 31, 2014 and 2013, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value:
		Level 1		Level 2			Level 3		Total
		Inputs		Inputs			Inputs		Fair Value
		(dollars in thousands)
	December 31, 2014
	Impaired loans	$	—	$	—		$	2,129	$	2,129
	December 31, 2013
	Impaired loans	$	—	$	—		$	5,491	$	5,491
	OREO	—		—			1,134		1,134
	The following table presents additional quantitative information about assets measured at fair value on a non-recurring basis for which the Company has utilized level 3 inputs to determine fair value:
		Quantitative Information about Level 3 Fair Value Measurements
		Fair Value		Valuation		Unobservable		Range
		Estimate		Techniques		Input		(Weighted Average)
		(dollars in thousands)
	December 31, 2014
	Impaired loans	$	2,129	Appraisal of collateral		Appraisal adjustments		-7.7% to -100.0%
								(-54.3%)
	December 31, 2013
	Impaired loans	$	5,491	Appraisal of collateral		Appraisal adjustments		-0.4% to -100.0%
								(-36.0%)
	OREO	1,134		Appraisal of collateral		Appraisal adjustments		-6.6% to -100.0%
								(-47.9%)
	FASB ASC Topic 825 requires disclosure of the fair value of financial assets and financial liabilities, including those financial assets and financial liabilities that are not measured and reported at fair value on a recurring basis or non-recurring basis. The methodologies for estimating the fair value of financial assets and financial liabilities that are measured at fair value on a recurring or non-recurring basis are discussed above. The estimated fair value approximates carrying value for cash and due from banks and accrued interest and are classified as level 2. The methodologies for other financial assets and financial liabilities are discussed below:
	Securities held to maturity
	Fair value measurements for securities held to maturity are from an independent pricing service. The independent pricing service evaluations are based on market data.  Securities held to maturity are classified as level 2.
	Loans held for sale
	Fair value of mortgage loans held for sale are based on commitments on hand from investors or prevailing market prices.
Fair values for on-balance-sheet commitments to originate loans held for sale are based on fees currently charged to enter into similar agreements, and for fixed-rate commitments also consider the difference between current levels of interest rates and the committed rates.  The fair value of interest rate lock commitments are considered immaterial.  Loans held for sale are classified as level 2.
Loans
Our performing loan portfolio consists of variable rate and fixed rate loans. For variable rate loans that reprice frequently with no significant change in credit risk, fair values are based on carrying amount. For certain homogeneous categories of loans, such as some residential mortgages, fair value is estimated using the quoted market prices for similar loans or securities backed by similar loans, adjusted for differences in loan characteristics. The fair value of other types of loans is estimated by discounting the future cash flows using the current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining maturities and are classified as level 3.  Fair value of impaired loans is discussed above.
Deposits and securities sold under agreements to repurchase
The fair value of demand deposits, savings accounts, interest-bearing transaction accounts, and certain money market deposits is defined as the amount payable on demand at the reporting date. The fair value of fixed-maturity certificates of deposit is estimated using a discounted cash flow calculation that applies interest rates currently offered for deposits of similar remaining maturities. The carrying amounts reported in the balance sheet for securities sold under agreements to repurchase approximate those liabilities’ fair values. Deposits and securities sold under agreements to repurchase are classified as level 2.
Long-term debt
Rates currently available to the Company for debt with similar terms and remaining maturities are used to estimate fair value of existing debt and are classified as level 2.
Junior subordinated debt owed to unconsolidated trusts
For variable rate instruments, fair values are based on carrying values and are classified as level 2.
Commitments to extend credit and standby letters of credit
The fair value of commitments is estimated using the fees currently charged to enter into similar agreements, taking into account the remaining terms of the agreements and the present creditworthiness of the counterparties. For fixed-rate loan commitments, fair value also considers the difference between current levels of interest rates and the committed rates.  The fair value of letters of credit is based on fees currently charged for similar agreements or on the estimated cost to terminate them or otherwise settle the obligations with the counterparties at the reporting date.  As of December 31, 2014 and 2013, these items were insignificant.
The estimated fair values of financial instruments that are reported at amortized cost in the Company’s Consolidated Balance Sheets, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value, were as follows:
	December 31, 2014					December 31, 2013
	Carrying		Fair			Carrying		Fair
	Amount		Value			Amount		Value
	(dollars in thousands)
Financial assets:
Level 2 inputs:
Cash and due from banks	$	339,438	$	339,438		$	231,603	$	231,603
Securities held to maturity	2,373		2,425			834		831
Loans held for sale	10,400		10,634			13,840		14,103
Accrued interest receivable	11,187		11,187			11,148		11,148
Level 3 inputs:
Loans, net	2,357,837		2,360,000			2,233,893		2,236,841
Financial liabilities:
Level 2 inputs:
Deposits	$	2,900,848	$	2,900,763		$	2,869,138	$	2,870,870
Securities sold under agreements to repurchase	198,893		198,893			172,348		172,348
Long-term debt	50,000		50,000			—		—
Junior subordinated debt owed to unconsolidated trusts	55,000		55,000			55,000		55,000
Accrued interest payable	507		507			673		673
Other assets and liabilities of the Company that are not defined as financial instruments are not included in the above disclosures, such as property and equipment. Also, nonfinancial instruments typically not recognized in financial statements nevertheless may have value but are not included in the above disclosures. These include, among other items, the estimated earning potential of core deposit accounts, the earnings potential of loan servicing rights, the earnings potential of the trust operations, customer goodwill and similar items.

Reportable_Segments_and_Relate

Reportable Segments and Related Information	12 Months Ended
	Dec. 31, 2014
Reportable Segments and Related Information
Reportable Segments and Related Information
	Note 21.  Reportable Segments and Related Information
	The Company has three reportable segments, Busey Bank, FirsTech and Busey Wealth Management.  Busey Bank provides a full range of banking services to individual and corporate customers through its branch network in downstate Illinois, through its branch in Indianapolis, Indiana, and through its branch network in southwest Florida.  FirsTech provides remittance processing for online bill payments, lockbox and walk-in payments.  Busey Wealth Management is the parent company of Busey Trust Company, which provides a full range of asset management, investment and fiduciary services to individuals, businesses and foundations, tax preparation and philanthropic advisory services.
	The Company’s three reportable segments are strategic business units that are separately managed as they offer different products and services and have different marketing strategies.
	The segment financial information provided below has been derived from the internal accounting system used by management to monitor and manage the financial performance of the Company. The accounting policies of the three segments are the same as those described in the summary of significant accounting policies in Note 1. The Company accounts for intersegment revenue and transfers at current market value.
	Following is a summary of selected financial information for the Company’s business segments:
		Goodwill						Total Assets
		2014			2013			2014			2013
		(dollars in thousands)						(dollars in thousands)
	As of December 31,
	Busey Bank	$	—		$	—		$	3,589,419		$	3,456,555
	FirsTech	8,992			8,992			28,540			27,253
	Busey Wealth Management	11,694			11,694			31,196			28,548
	All Other	—			—			16,452			27,219
	Totals	$	20,686		$	20,686		$	3,665,607		$	3,539,575
		Year ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Interest Income:
	Busey Bank	$	107,766		$	108,413		$	116,608
	FirsTech	52			51			62
	Busey Wealth Management	287			242			251
	All Other	(30		)	(10		)	(5		)
	Total interest income	$	108,075		$	108,696		$	116,916
	Interest Expense:
	Busey Bank	$	5,355		$	7,448		$	13,466
	FirsTech	—			—			—
	Busey Wealth Management	—			—			—
	All Other	1,144			1,183			1,304
	Total interest expense	$	6,499		$	8,631		$	14,770
	Other Income:
	Busey Bank	$	32,452		$	36,774		$	39,908
	FirsTech	9,561			8,541			8,522
	Busey Wealth Management	18,953			17,799			16,345
	All Other	(2,025		)	(531		)	2,077
	Total other income	$	58,941		$	62,583		$	66,852
	Net Income:
	Busey Bank	$	30,764		$	25,416		$	19,162
	FirsTech	1,227			1,000			935
	Busey Wealth Management	4,681			4,242			3,363
	All Other	(3,898		)	(1,932		)	(1,103		)
	Total net income	$	32,774		$	28,726		$	22,357

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2014
Acquisitions
Acquisitions
	Note 22: Acquisitions
	On January 8, 2015, First Busey completed its acquisition of Herget Financial, headquartered in Pekin, Illinois and its wholly-owned bank subsidiary, Herget Bank.  Herget Bank operates three branches in Pekin, Illinois.  The acquisition of Herget Financial allows us to further increase our presence in the Pekin and greater Peoria market.  Additionally, Herget Financial holds a dominant deposit market position in its community and offers trust, estate and asset management services, as well as competitive commercial loan and mortgage offerings, all of which complement First Busey’s offerings. First Busey acquired 100% of Herget Financial’s outstanding common stock for aggregate cash consideration of $34.1 million.  Each share of Herget Financial common stock received $588.00 in cash.
	First Busey will operate Herget Bank as a separate banking subsidiary from January 9, 2015 until it is merged with Busey Bank, which is expected to occur shortly after the filing of this Form 10-K.  At that time, Herget Bank’s banking offices will become branches of Busey Bank.
	This transaction will be accounted for using the acquisition method of accounting and, accordingly, assets acquired, liabilities assumed, and consideration exchanged will be recorded at estimated fair values on the date of acquisition.  Fair value assessments are incomplete as of the filing date of this Form 10-K.  Fair values are subject to refinement for up to one year after the closing date of January 8, 2015.
	During 2014, First Busey incurred $0.4 million of acquisition expenses related to this transaction, comprised primarily of legal, accounting, and system conversion costs.  As of December 31, 2014, Herget Financial and Herget Bank had total consolidated assets of $278.8 million, total investments of $113.0 million, total gross loans of $112.6 million and total deposits of $246.4 million.

Parent_Company_Only_Financial_

Parent Company Only Financial Information	12 Months Ended
	Dec. 31, 2014
Parent Company Only Financial Information
Parent Company Only Financial Information
	Note 23.  Parent Company Only Financial Information
	Condensed financial data for First Busey Corporation is presented below.
	BALANCE SHEETS
		December 31,
		2014			2013
		(dollars in thousands)
	ASSETS
	Cash and due from subsidiary banks	$	84,537		$	42,645
	Securities available for sale	201			201
	Investments in subsidiaries:
	Bank	373,773			400,442
	Non-bank	28,348			25,646
	Premises and equipment, net	523			521
	Other assets	8,684			9,450
	Total assets	$	496,066		$	478,905
	LIABILITIES AND STOCKHOLDERS’ EQUITY
	Liabilities:
	Junior subordinated debentures owed to unconsolidated
	Trusts	$	55,000		$	55,000
	Other liabilities	7,427			8,541
	Total liabilities	62,427			63,541
	Total stockholders’ equity	433,639			415,364
	Total liabilities and stockholders’ equity	$	496,066		$	478,905
	STATEMENTS OF INCOME
		Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Operating income:
	Dividends from subsidiaries:
	Bank	$	—		$	—		$	—
	Non-bank	2,000			2,000			2,500
	Interest and dividend income	20			46			49
	Other income	3,475			4,669			6,231
	Total operating income	5,495			6,715			8,780
	Expense:
	Salaries and employee benefits	6,778			5,139			4,718
	Interest expense	1,183			1,220			1,351
	Operating expense	2,563			2,163			2,469
	Total expense	10,524			8,522			8,538
	(Loss) income before income tax benefit and distributions less than net income of subsidiaries	(5,029		)	(1,807		)	242
	Income tax benefit	3,131			1,875			1,155
	(Loss) income before distributions less than net income of subsidiaries	(1,898		)	68			1,397
	Distributions less than net income of subsidiaries:
	Bank	31,991			26,416			20,097
	Non-bank	2,681			2,242			863
	Net income	$	32,774		$	28,726		$	22,357
	STATEMENTS OF CASH FLOWS
		Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Cash Flows from Operating Activities
	Net income	$	32,774		$	28,726		$	22,357
	Adjustments to reconcile net income to net cash provided by (used in) operating activities:
	Depreciation and amortization	112			100			98
	Distributions less than net income of subsidiaries	(34,672		)	(28,658		)	(20,960		)
	Stock-based compensation	1,187			1,079			991
	Fair value adjustment on employee stock ownership plan shares allocated	—			—			(322		)
	Changes in assets and liabilities:
	Decrease (increase) in other assets	951			(62		)	125
	(Decrease) increase in other liabilities	(1,077		)	381			1,435
	Net cash (used in) provided by operating activities	(725		)	1,566			3,724
	Cash Flows from Investing Activities
	Decrease in loans	—			68			95
Proceeds from sales of premises and equipment	—			226			—
Purchases of premises and equipment	(114		)	(90		)	(11		)
Net cash (used in) provided by investing activities	(114		)	204			84
Cash Flows from Financing Activities
Proceeds from charter amendment with subsidiary bank	60,000			50,000			—
Shares surrendered upon vesting of restricted stock units to cover tax obligations	(45		)	(237		)	—
Cash dividends paid	(17,224		)	(14,040		)	(24,427		)
Net cash provided by (used in) financing activities	42,731			35,723			(24,427		)
Net increase (decrease) in cash and due from subsidiary banks	41,892			37,493			(20,619		)
Cash and due from subsidiary banks, beginning	42,645			5,152			25,771
Cash and due from subsidiary banks, ending	$	84,537		$	42,645		$	5,152

Unaudited_Interim_Financial_Da

Unaudited Interim Financial Data	12 Months Ended
	Dec. 31, 2014
Unaudited Interim Financial Data
Unaudited Interim Financial Data
	Note 24.  Unaudited Interim Financial Data
	The following table reflects summarized quarterly data for the periods described (unaudited), in thousands, except per share data:
		2014
		December 31		September 30		June 30		March 31
	Interest income	$	27,657	$	27,511	$	26,656	$	26,251
	Interest expense	1,570		1,600		1,635		1,694
	Net interest income	26,087		25,911		25,021		24,557
	Provision for loan losses	—		—		1,000		1,000
	Non-interest income	14,739		14,204		15,012		14,986
	Non-interest expense	28,470		26,298		26,823		26,618
	Income before income taxes	12,356		13,817		12,210		11,925
	Income taxes	4,763		4,708		4,025		4,038
	Net income	$	7,593	$	9,109	$	8,185	$	7,887
	Preferred stock dividends	182		182		181		182
	Net income available to common stockholders	$	7,411	$	8,927	$	8,004	$	7,705
	Basic earnings per share	$	0.08	$	0.10	$	0.09	$	0.09
	Diluted earnings per share	$	0.08	$	0.10	$	0.09	$	0.09
		2013
		December 31		September 30		June 30		March 31
	Interest income	$	26,885	$	27,236	$	27,460	$	27,115
	Interest expense	1,881		2,003		2,215		2,532
	Net interest income	25,004		25,233		25,245		24,583
	Provision for loan losses	1,500		2,000		2,000		2,000
	Non-interest income	14,529		15,630		15,783		16,641
	Non-interest expense	27,585		27,358		27,801		29,567
	Income before income taxes	10,448		11,505		11,227		9,657
	Income taxes	3,528		3,572		3,787		3,224
	Net income	$	6,920	$	7,933	$	7,440	$	6,433
	Preferred stock dividends	908		909		908		908
	Net income available to common stockholders	$	6,012	$	7,024	$	6,532	$	5,525
	Basic earnings per share	$	0.07	$	0.08	$	0.08	$	0.06
	Diluted earnings per share	$	0.07	$	0.08	$	0.08	$	0.06

Significant_Accounting_Policie1

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Significant Accounting Policies
Basis of consolidation	Basis of consolidation
	The Consolidated Financial Statements include the accounts of the Company and its subsidiaries: Busey Bank and its wholly-owned subsidiary FirsTech, Inc.; and Busey Wealth Management, Inc. and its wholly-owned subsidiaries Busey Trust Company and Busey Capital Management, Inc.  The Company and its subsidiaries maintain various LLCs that hold specific assets for risk mitigation purposes and are consolidated into these financial statements.  All significant intercompany balances and transactions have been eliminated in consolidation.
	The Consolidated Financial Statements also exclude the following wholly-owned variable interest entities:  First Busey Statutory Trust II, First Busey Statutory Trust III and First Busey Statutory Trust IV because the Company is not the primary beneficiary.
	The Consolidated Financial Statements of the Company have been prepared in conformity with accounting principles generally accepted in the United States of America and conform to predominant practice within the banking industry.
Use of estimates	Use of estimates
	In preparing the accompanying Consolidated Financial Statements, the Company’s management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses for the reporting period.  Actual results could differ from those estimates.  Material estimates which are particularly susceptible to significant change in the near-term relate to the fair value of investment securities, the determination of the allowance for loan losses and the ability to realize its deferred tax assets.
Comprehensive income	Comprehensive income
	Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income.  Although certain changes in assets and liabilities, such as unrealized gains and losses on available for sale securities, are reported as a separate component of the equity section of the balance sheet, such items, along with net income, are components of comprehensive income.
Trust assets	Trust assets
	Assets held for customers in a fiduciary or agency capacity, other than trust cash on deposit at the Company’s bank subsidiary, are not assets of the Company and, accordingly, are not included in the accompanying Consolidated Financial Statements.  Busey Trust Company had assets under care of $5.2 billion and $5.0 billion at December 31, 2014 and 2013, respectively.
Cash flows	Cash flows
	For purposes of the consolidated statement of cash flows, cash and due from banks includes cash on hand and amounts due from banks.  Cash flows from federal funds purchased and sold, short-term borrowings, and securities sold under agreements to repurchase are reported net, since their original maturities are less than three months.  Cash flows from loans and deposits are also reported net.
Securities	Securities
	Securities classified as held to maturity are those debt securities that the Company intends to hold to maturity.  Securities held to maturity are carried at cost, adjusted for amortization of premiums and accretion of discounts.
	Securities classified as available for sale are those debt securities that the Company intends to hold for an indefinite period of time, but not necessarily to maturity, and marketable equity securities.  Any decision to sell a security classified as available for sale would be based on various factors, including significant movements in interest rates, changes in the maturity mix of the Company’s assets and liabilities, liquidity needs, regulatory capital considerations and other similar factors.  Securities available for sale are carried at fair value, with temporary unrealized gains and losses excluded from earnings and reported in other comprehensive income.
	Declines in the fair value of debt securities below their amortized cost are evaluated to determine whether the loss is temporary or other-than-temporary.  If the Company (a) has the intent to sell a debt security or (b) more likely than not will be required to sell the debt security before its anticipated recovery, then the Company recognizes the entire unrealized loss in earnings as an other-than-temporary loss.  If neither of these conditions are met, the Company evaluates whether a credit loss exists.  The impairment is separated into (x) the amount of the total impairment related to the credit loss and (y) the amount of total impairment related to all other factors.  The amount of the total other-than-temporary impairment related to the credit loss is recognized in earnings and the amount related to all other factors is recognized in other comprehensive income.
	The Company also evaluates whether the decline in fair value of an equity security is temporary or other-than-temporary.  In determining whether an unrealized loss on an equity security is temporary or other-than-temporary, management considers various factors, including the magnitude and duration of the impairment, the financial condition and near-term prospects of the issuer, and the intent and ability of the Company to hold the equity security to forecasted recovery.
	Purchase premiums and discounts are recognized in interest income using the interest method over the terms of the securities.  Gains and losses on the sale of securities are recorded on the trade date and are determined using the specific identification method.
Loans held for sale	Loans held for sale
	Loans held for sale are those loans the Company has the intent to sell in the foreseeable future.  They consist of mortgage loans conforming to established guidelines and held for sale to investors and the secondary mortgage market.  Loans held for sale are carried at the lower of aggregate cost or estimated fair value, as determined by aggregate outstanding commitments from investors or current investor yield requirements.  Net unrealized losses, if any, are recognized through a valuation allowance by charges to income.  Gains and losses on sales of loans are recognized at settlement dates and are determined by the difference between the sales proceeds and the carrying amount of the loans after allocating cost to servicing rights retained.
	The Company enters into commitments to originate loans whereby the interest rate on the loan is determined prior to funding (rate lock commitments).  Rate lock commitments on mortgage loans that are intended to be sold are considered to be derivatives.  To avoid interest rate risk, the Company also enters into mortgage loan sales commitments at the time it makes the interest rate lock commitment.  Accordingly, such commitments along with any related fees received from potential borrowers are recorded at fair value, with changes in fair value recorded in the net gain or loss on sale of mortgage loans.  Fair value is based on the change in estimated fair value of the underlying mortgage loan.  The fair value is subject to change primarily due to changes in interest rates and is considered immaterial to the Consolidated Financial Statements.
Loan servicing	Loan servicing
	Servicing assets are recognized as separate assets when rights are acquired or retained through the sale of mortgage loans.  Mortgage servicing rights are initially recorded at fair value.  Fair value is based on a valuation model that calculates the present value of estimated future net servicing income.  Capitalized servicing rights are reported in other assets and are amortized into other income in proportion to, and over the period of, the estimated future net servicing income of the underlying financial assets.
	Mortgage servicing rights are periodically evaluated for impairment based on the fair value of those rights as compared to book value.  Fair values are estimated using discounted cash flows based on current expected future prepayment rates.  For purposes of measuring impairment, the rights must be stratified by one or more predominant risk characteristics of the underlying loans.  The Company stratifies its capitalized mortgage servicing rights based on the type of the underlying loans.  The amount of impairment recognized is the amount, if any, by which the amortized cost of the rights for each stratum exceeds its fair value.  If the Company later determines that all or a portion of the impairment no longer exists for a particular group of loans, a reduction of the allowance may be recorded as an increase to income.
	Servicing fee income is recorded for fees earned for servicing loans.  The fees are based on a contractual percentage of the outstanding principal and are recorded as income when earned.  The amortization of mortgage servicing rights is netted against loan servicing fee income.
Loans	Loans
	Loans receivable that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off are stated at the amount of outstanding unpaid principal, adjusted for chargeoffs, the allowance for loan losses, and any deferred origination fees or costs on loans.
	Retail loan origination fees, net of certain direct loan origination costs, are deferred and the net amount is amortized as an adjustment of the related loan’s yield.  The Company is generally amortizing these amounts over the contractual life.  However, for long-term, fixed-rate residential mortgages, the Company has anticipated prepayments and assumes an estimated economic life of five years or less. Material commercial loan origination fees are amortized over the life of the loan which is usually a term of three years or less.  Commitment fees and costs are generally based upon a percentage of a customer’s maximum line of credit or fees related to standby letters of credit and are recognized as collected.
	Interest is accrued daily on the outstanding balances.  Loans are placed on non-accrual status when, in management’s opinion, the borrower may be unable to meet payment obligations as they become due, as well as when required by regulatory provisions.  Loans may be placed on non-accrual status regardless of whether or not such loans are considered past due.  Past due status is based on the contractual terms of the loan.
	Interest accrued in the current year but not collected for loans that are placed on non-accrual status or charged-off is reversed against interest income.  Interest accrued during the prior year but not collected for loans that are placed on non-accrual status or charged-off is charged against the allowance for loan losses.  The interest on these loans is accounted for on the cash-basis or cost-recovery method, until qualifying for return to accrual status.  Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured.
Allowance for loan losses	Allowance for loan losses
	The allowance for loan losses is established as losses are estimated to have occurred through a provision for loan losses charged to earnings.  Loan losses are charged against the allowance for loan losses when management believes the uncollectibility of the loan balance is confirmed.  Subsequent recoveries, if any, are credited to the allowance.
	The allowance for loan losses is evaluated on a regular basis by management and is based upon management’s periodic review of the collectibility of the loans in light of historical experience, the nature and volume of the loan portfolio, adverse situations that may affect the borrower’s ability to repay, estimated value of any underlying collateral and prevailing economic conditions.  This evaluation is inherently subjective as it requires estimates that are susceptible to significant revision as more information becomes available.
	In addition, regulatory agencies, as an integral part of their examination process, periodically review the allowance for loan losses, and may require the Company to make additions to the allowance based on their judgment about information available to them at the time of their examinations.
	The allowance consists of specific and general components.  The specific component considers loans that are classified as impaired.  For such loans that are classified as impaired, an allowance is established when the discounted cash flows (or collateral value or observable market price) of the impaired loan is lower than the carrying amount of that loan.  The general component covers non-classified loans and classified loans not considered impaired, and is based on historical loss experience adjusted for qualitative factors.  Other adjustments may be made to the allowance for pools of loans after an assessment of internal or external influences on credit quality that are not fully reflected in the historical loss experience.
Premises and equipment	Premises and equipment
	Land is stated at cost less accumulated depreciation of depreciable land improvements.  Premises and equipment are stated at cost less accumulated depreciation.  Depreciation is computed principally by the straight-line method over the estimated useful lives of the assets.  The estimated useful lives for premises and equipment are:
	Asset Description	Estimated Useful Life
	Buildings and improvements	3 – 40 years
	Furniture and equipment	3 – 10 years
Long-lived assets	Long-lived assets
	Long-lived assets, including premises and equipment and intangible assets, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable.  An impairment loss would be recognized when estimated undiscounted future cash flows from operations of the asset are less than the carrying value of the asset.  The cash flows used for this analysis are those directly associated with and that are expected to arise as a direct result of the use and eventual disposition of the asset.  An impairment loss would be measured by the amount by which the carrying value of the asset exceeds its fair value.
Other real estate owned	Other real estate owned
	OREO represents properties acquired through foreclosure or other proceedings in settlement of loans.  OREO is held for sale and is recorded at the date of foreclosure at the fair value of the properties less estimated costs of disposal, which establishes a new cost basis.  Any adjustment to fair value at the time of transfer to OREO is charged to the allowance for loan losses.  Property is evaluated regularly to ensure the recorded amount is supported by its current fair value, and valuation allowances to reduce the carrying amount to fair value less estimated costs to dispose are recorded as necessary.  Revenue, expense, gains and losses from the operations of foreclosed assets are included in operations.
Goodwill	Goodwill
	Goodwill represents the excess of the cost of a business acquired over the fair value of the new assets acquired.  Goodwill is not amortized, but is subject to at least annual impairment assessments.  The Company has established December 31 as the annual impairment assessment date.  Accounting standards allow for goodwill to be tested for impairment by first performing a qualitative assessment to determine whether it is more likely than not that the fair value of the reporting unit is less than its carrying value.  If the reporting unit does not pass the qualitative assessment, then the reporting unit’s carrying value is compared to its fair value. The Company estimates the fair value of its reporting units as of the measurement date utilizing valuation methodologies including the comparable transactions approach and the control premium approach.  Goodwill is considered impaired if the carrying value of the reporting unit exceeds its fair value. There was no impairment determined at December 31, 2014 and 2013.  It is possible the Company will evaluate its goodwill for impairment on a more frequent basis than annually.  Future evaluations may result in impairment.  See Note 7 — Goodwill and Other Intangible Assets for further discussion.
Cash surrender value of bank-owned life insurance	Cash surrender value of bank-owned life insurance
	The Company has purchased life insurance policies on certain executives and senior officers.  Life insurance is recorded at its cash surrender value.
	ASC Topic 715, “Compensation—Retirement Benefits” requires an employer to recognize a liability for post-employment benefits promised to an employee based on an arrangement between an employer and an employee. In an endorsement split-dollar arrangement, the employer owns and controls the policy, and the employer and employee split the life insurance policy’s cash surrender value and/or death benefits. If the employer agrees to maintain a life insurance policy during the employee’s retirement, the present value of the cost of maintaining the insurance policy would be accrued over the employee’s active service period. Similarly, if the employer agrees to provide the employee with a death benefit, the present value of the death benefit would be accrued over the employee’s active service period.
Transfers of financial assets	Transfers of financial assets
	Transfers of financial assets are accounted for as sales only when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when: (1) the assets have been isolated from the Company, (2) the transferee obtains the right to pledge or exchange the assets it received, and no condition both constrains the transferee from taking advantage of its right to pledge or exchange and provides more than a modest benefit to the transferor, and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity or the ability to unilaterally cause the holder to return specific assets.
Income taxes	Income taxes
	The Company is subject to income taxes in the U.S. federal and various state jurisdictions.  The Company and its subsidiaries file consolidated federal and state income tax returns with each subsidiary computing its taxes on a separate entity basis.  Tax regulations within each jurisdiction are subject to the interpretation of the related tax laws and regulations and require significant judgment to apply.  With few exceptions, the Company is no longer subject to U.S. federal, state or local tax examinations by tax authorities for the years before 2010.  The provision for income taxes is based on income as reported in the Consolidated Financial Statements.
	The Company has maintained significant net deferred tax assets for deductible temporary differences, the largest of which relates to the State of Illinois net operating loss carryforward and the allowance for loan losses. For income tax return purposes, only actual charge-offs are deductible, not the provision for loan losses. Under generally accepted accounting principles, a valuation allowance is required to be recognized if it is more likely than not that the deferred tax assets will not be realized. The determination of the recoverability of the deferred tax assets is highly subjective and dependent upon judgment concerning management’s evaluation of both positive and negative evidence, the forecasts of future income, applicable tax planning strategies, and assessments of the current and future economic and business conditions. The Company considers both positive and negative evidence regarding the ultimate recoverability of its deferred tax assets. Positive evidence includes available tax planning strategies and the probability that taxable income will continue to be generated in future periods, as it was in periods since March 31, 2010, while negative evidence includes a cumulative loss in 2009 and 2008 and certain business and economic trends. The Company evaluated the recoverability of its net deferred tax assets and established a valuation allowance for certain state net operating loss and credit carryforwards that are not expected to be fully realized. Management believes that it is more likely than not that the other deferred tax assets included in the accompanying Consolidated Financial Statements will be fully realized. The Company determined that no valuation allowance was required for any other deferred tax assets as of December 31, 2014, although there is no guarantee that those assets will be recognizable in future periods.
	The Company must assess the likelihood that any deferred tax assets will be realized through the reduction of taxes in future periods and establish a valuation allowance for those assets for which recovery is not more likely than not. In making this assessment, the Company must make judgments and estimates regarding the ability to realize the asset through the future reversal of existing taxable temporary differences, future taxable income, and the possible application of future tax planning strategies.  The Company’s evaluation gave consideration to the fact that all net operating loss carrybacks have been utilized.  Therefore, utilization of net operating loss carryforwards are dependent on implementation of tax strategies and continued profitability.
	Positions taken in tax returns may be subject to challenge upon examination by the taxing authorities. Uncertain tax positions are initially recognized in the Financial Statements when it is more likely than not the position will be sustained upon examination by the tax authorities. Such tax positions are both initially and subsequently measured as the largest amount of tax benefit that has a greater than 50% likelihood of being realized upon settlement with the tax authority, assuming full knowledge of the position and all relevant facts.  When applicable, the Company recognizes interest accrued related to unrecognized tax benefits and penalties in operating expenses.  The Company had no accruals for payments of interest and penalties at December 31, 2014 and 2013.
	At December 31, 2014, the Company was under examination by the Illinois Department of Revenue for the Company’s 2011 and 2012 income tax filings.
Reclassifications	Reclassifications
	Reclassifications have been made to certain prior year account balances, with no effect on net income or stockholders’ equity, to be consistent with the classifications adopted as of and for the year ended December 31, 2014.
Stock-based employee compensation	Stock-based employee compensation
	During the second quarter of 2010, the Company adopted the First Busey Corporation 2010 Equity Incentive Plan (“2010 Equity Plan”), which was approved at the annual stockholders meeting on May 19, 2010. The Company will no longer make any additional grants under prior plans.
	The Company’s equity incentive plans are designed to encourage ownership of its common stock by its employees and directors, to provide additional incentive for them to promote the success of the Company’s business, and to attract and retain talented personnel. All of the Company’s employees and directors and those of its subsidiaries are eligible to receive awards under the plans. See Note 16 — Stock Incentive Plans for further discussion.
	The Company calculates the compensation cost of its non-vested stock awards (restricted stock units) based on the Company’s stock price on the grant date multiplied by the number of units granted. This cost is recorded over a specified requisite service period (i.e. vesting period) ranging from one to five years. As the units cliff vest and are subject only to a service condition, the cost is recorded using straight-line amortization. No compensation cost is recognized for unvested awards that are forfeited.
Segment disclosure	Segment disclosure
	Operating segments are components of a business that (i) engage in business activities from which it may earn revenues and incur expenses; (ii) have operating results that are reviewed regularly by the entity’s chief operating decision maker to make decisions about resources to be allocated to the segments and assess their performance; and (iii) for which discrete financial information is available. The Company’s segments are its three primary operating subsidiaries Busey Bank, FirsTech and Busey Wealth Management.
Business Combinations	Business Combinations
	Business combinations are accounted for under ASC 805, Business Combinations, using the acquisition method of accounting. The acquisition method of accounting requires an acquirer to recognize the assets acquired and the liabilities assumed at the acquisition date measured at their fair values as of that date. To determine the fair values, the Company may rely on third party valuations, such as appraisals, or internal valuations based on discounted cash flow analyses or other valuation techniques. Under the acquisition method of accounting, the Company will identify the acquirer and the closing date and apply applicable recognition principles.
	On January 8, 2015, First Busey completed its acquisition of Herget Financial, headquartered in Pekin, Illinois.  This acquisition is a subsequent event and financial results of Herget Financial are not recognized in this Form 10-K.
	Acquisition related costs are costs the Company incurs to effect a business combination.  Those costs may include legal, accounting, valuation, other professional or consulting fees, system conversions and marketing costs. The Company will account for acquisition related costs as expenses in the periods in which the costs are incurred and the services are received.  Costs that the Company expects, but is not obligated to incur in the future, to effect its plan to exit an activity of an acquiree or to terminate the employment of an acquiree’s employees are not liabilities at the acquisition date. Instead, the Company will recognize these costs in its post-combination financial statements in accordance with other applicable accounting guidance.
	During 2014, First Busey incurred $0.4 million of acquisition expenses related to the acquisition of Herget Financial, comprised primarily of legal, accounting, and system conversion costs.
Derivative Financial Instruments	Derivative Financial Instruments
	The Company enters into derivative financial instruments as part of its foreign currency risk management strategies.  These derivative financial instruments consist of foreign currency forward contracts to accommodate the business needs of its customers.  The derivative instruments are recorded on the balance sheet, as either an asset or liability, at their fair value.  For derivative instruments not accounted for as hedges, changes in fair value are recognized in other income.
Earnings per share	Earnings per share
	Basic earnings per share are computed by dividing net income available to common stockholders for the period by the weighted average number of common shares outstanding.
	Diluted earnings per common share is computed using the treasury stock method and reflects the potential dilution that could occur if the Company’s outstanding stock options were exercised and restricted stock units were vested.  Stock options and restricted stock units for which the exercise or the grant price exceeds the average market price over the period have an anti-dilutive effect and are excluded from the calculation.  At December 31, 2014, 457,630 outstanding options, 573,833 warrants, and 353,976 restricted stock units were anti-dilutive and excluded from the calculation of common stock equivalents.  At December 31, 2013, 643,879 outstanding options, 573,833 warrants, and 347,253 restricted stock units were anti-dilutive and excluded from the calculation of common stock equivalents.
	The following reflects net income per share calculations for basic and diluted methods:
		For the Years Ended December 31,
		2014		2013		2012
		(in thousands, except per share data)
	Net income available to common stockholders	$	32,047	$	25,093	$	18,724
	Shares:
	Weighted average common shares outstanding	86,906		86,765		86,643
	Dilutive effect of outstanding options, warrants and restricted stock units as determined by the application of the treasury stock method	386		299		9
	Weighted average common shares outstanding, as adjusted for diluted earnings per share calculation	87,292		87,064		86,652
	Basic earnings per common share	$	0.37	$	0.29	$	0.22
	Diluted earnings per common share	$	0.37	$	0.29	$	0.22
Subsequent events	Subsequent events
	The Company has evaluated subsequent events for potential recognition and/or disclosure through the date the Consolidated Financial Statements included in this Annual Report on Form 10-K were issued.  On January 8, 2015, First Busey completed its acquisition of Herget Financial, headquartered in Pekin, Illinois.  See Note 22 — Acquisitions for further discussion.  On February 3, 2015, First Busey’s board of directors approved a repurchase plan under which the Company is authorized to repurchase its common stock.  See Note 16 — Stock Incentive Plans for further discussion.  Other than the completion of the acquisition of Herget Financial and stock repurchase approval, there were no significant subsequent events for the year ended December 31, 2014 through the filing date of these Consolidated Financial Statements.
Impact of new financial accounting standards	Impact of new financial accounting standards
	ASU 2014-04, “Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) - Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure.” ASU 2014-04 clarifies when an in-substance repossession or foreclosure occurs and requires interim and annual disclosures.  The new authoritative guidance will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2014 and is not expected to have a significant impact on the Company’s financial statements.
	ASU 2014-09, “Revenue from Contracts with Customers (Topic 606).”  ASU 2014-09 outlines a single model for companies to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. ASU 2014-09 will require that companies recognize revenue based on the value of transferred goods or services as they occur in the contract and will also require additional disclosures.  The new authoritative guidance will be for reporting periods after December 15, 2016, and the Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures.
	ASU 2014-14, “Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) — Classification of Certain Government-Guaranteed Mortgage Loans upon Foreclosure.” ASU 2014-14 requires that certain government-guaranteed mortgage loans be derecognized and that a separate other receivable be recognized upon foreclosure if certain conditions are met. Upon foreclosure on loans that meet these criteria, a separate receivable should be recorded based on the amount of the loan balance expected to be recovered from the guarantor. The new authoritative guidance will be effective for fiscal years, and interim periods within those years, beginning after December 15, 2014 and is not expected to have a significant impact on the Company’s financial statements.
	ASU 2014-17, “Business Combinations (Topic 805): Pushdown Accounting.”  ASU 2014-17 provides guidance on whether and at what threshold an acquired entity can apply pushdown accounting in its separate financial statements upon occurrence of an event in which an acquirer obtains control of the acquired entity.  The new authoritative guidance became effective upon issuance on November 18, 2014 and had no impact on the Company’s financial statements.

Significant_Accounting_Policie2

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Significant Accounting Policies
Schedule of estimated useful lives for premises and equipment
	Asset Description	Estimated Useful Life
	Buildings and improvements	3 – 40 years
	Furniture and equipment	3 – 10 years
Schedule of net income per share calculations for basic and diluted methods
		For the Years Ended December 31,
		2014		2013		2012
		(in thousands, except per share data)
	Net income available to common stockholders	$	32,047	$	25,093	$	18,724
	Shares:
	Weighted average common shares outstanding	86,906		86,765		86,643
	Dilutive effect of outstanding options, warrants and restricted stock units as determined by the application of the treasury stock method	386		299		9
	Weighted average common shares outstanding, as adjusted for diluted earnings per share calculation	87,292		87,064		86,652
	Basic earnings per common share	$	0.37	$	0.29	$	0.22
	Diluted earnings per common share	$	0.37	$	0.29	$	0.22

Securities_Tables

Securities (Tables)	12 Months Ended
	Dec. 31, 2014
Securities
Schedule of amortized cost, unrealized gains and losses and fair values of securities classified available for sale and held to maturity
					Gross			Gross
		Amortized			Unrealized			Unrealized			Fair
		Cost			Gains			Losses			Value
		(dollars in thousands)
	December 31, 2014:
	Available for sale
	U.S. Treasury securities	$	50,280		$	328		$	(2	)	$	50,606
	Obligations of U.S. government corporations and agencies	166,207			981			(178		)	167,010
	Obligations of states and political subdivisions	218,250			2,672			(761		)	220,161
	Residential mortgage-backed securities	230,596			5,062			(22		)	235,636
	Corporate debt securities	79,087			296			(76		)	79,307
	Total debt securities	744,420			9,339			(1,039		)	752,720
	Mutual funds and other equity securities	4,944			1,401			—			6,345
	Total	$	749,364		$	10,740		$	(1,039	)	$	759,065
	Held to maturity
	Obligations of states and political subdivisions	$	1,359		$	15		$	(3	)	$	1,371
	Commercial mortgage-backed securities	1,014			40			—			1,054
	Total	$	2,373		$	55		$	(3	)	$	2,425
					Gross			Gross
		Amortized			Unrealized			Unrealized			Fair
		Cost			Gains			Losses			Value
		(dollars in thousands)
	December 31, 2013:
	Available for sale
	U.S. Treasury securities	$	102,463		$	244		$	(67	)	$	102,640
	Obligations of U.S. government corporations and agencies	254,998			2,741			(328		)	257,411
	Obligations of states and political subdivisions	272,077			2,887			(2,812		)	272,152
	Residential mortgage-backed securities	174,699			3,571			(535		)	177,735
	Corporate debt securities	25,384			155			(33		)	25,506
	Total debt securities	829,621			9,598			(3,775		)	835,444
	Mutual funds and other equity securities	4,114			1,752			—			5,866
	Total	$	833,735		$	11,350		$	(3,775	)	$	841,310
	Held to maturity
	Obligations of states and political subdivisions	$	834		$	1		$	(4	)	$	831
	Total	$	834		$	1		$	(4	)	$	831
Schedule of amortized cost and fair value of debt securities available for sale and held to maturity by contractual maturity
		Available for sale						Held to maturity
		Amortized			Fair			Amortized			Fair
		Cost			Value			Cost			Value
		(dollars in thousands)						(dollars in thousands)
	Due in one year or less	$	125,672		$	126,252		$	72		$	72
	Due after one year through five years	347,781			349,168			636			636
	Due after five years through ten years	120,891			124,483			1,665			1,717
	Due after ten years	150,076			152,817			—			—
	Total	$	744,420		$	752,720		$	2,373		$	2,425
Schedule of realized gains and losses related to sales of securities available for sale
		For the Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Gross security gains	$	807		$	599		$	1,602
	Gross security (losses)	(31		)	(46		)	(5		)
	Net security gains	$	776		$	553		$	1,597
Schedule of securities with gross unrealized losses aggregated by investment category and length of time that individual securities have been in continuous loss position
		Continuous unrealized						Continuous unrealized					Total, gross
		losses existing for less than						losses existing for greater
		12 months, gross						than 12 months, gross
		Fair			Unrealized			Fair			Unrealized		Fair		Unrealized
		Value			Losses			Value			Losses		Value		Losses
		(dollars in thousands)
	December 31, 2014:
	Available for sale
	U.S. Treasury securities	$	—		$	—		$	366		$	2	$	366	$	2
	Obligations of U.S. government corporations and agencies	—			—			25,118			178		25,118		178
	Obligations of states and political subdivisions	40,385			140			40,201			621		80,586		761
	Residential mortgage-backed securities	10,630			22			—			—		10,630		22
	Corporate debt securities	16,400			72			213			4		16,613		76
	Total temporarily impaired Securities	$	67,415		$	234		$	65,898		$	805	$	133,313	$	1,039
	Held to maturity
	Obligations of states and political subdivisions	$	534		$	3		$	—		$	—	$	534	$	3
	Total temporarily impaired Securities	$	534		$	3		$	—		$	—	$	534	$	3
		Continuous unrealized						Continuous unrealized					Total, gross
		losses existing for less than						losses existing for greater
		12 months, gross						than 12 months, gross
		Fair			Unrealized			Fair			Unrealized		Fair		Unrealized
		Value			Losses			Value			Losses		Value		Losses
		(dollars in thousands)
	December 31, 2013:
	Available for sale
	U.S. Treasury securities	$	25,830		$	67		$	—		$	—	$	25,830	$	67
	Obligations of U.S. government corporations and agencies	25,946			328			—			—		25,946		328
	Obligations of states and political subdivisions	92,703			2,518			8,492			294		101,195		2,812
	Residential mortgage-backed securities	53,543			535			—			—		53,543		535
	Corporate debt securities	1,614			33			—			—		1,614		33
	Total temporarily impaired Securities	$	199,636		$	3,481		$	8,492		$	294	$	208,128	$	3,775
	Held to maturity
	Obligations of states and political subdivisions	$	597		$	4		$	—		$	—	$	597	$	4
	Total temporarily impaired Securities	$	597		$	4		$	—		$	—	$	597	$	4
General obligation bonds
Securities
Summary of amortized cost and fair values of the Company's portfolio of municipal bonds by issuer state
	December 31, 2014:
										Average Exposure
		Number of		Amortized			Fair			Per Issuer
	U.S. State	Issuers		Cost			Value			(Fair Value)
		(dollars in thousands)
	Illinois	63		$	59,979		$	61,058		$	969
	Wisconsin	39		36,165			36,365			932
	Michigan	33		30,400			30,739			931
	Pennsylvania	10		12,756			12,761			1,276
	Ohio	8		9,954			9,922			1,240
	Texas	7		7,364			7,313			1,045
	Iowa	3		6,116			6,142			2,047
	Other	24		18,862			19,370			807
	Total general obligations bonds	187		$	181,596		$	183,670		$	982
	December 31, 2013:
										Average Exposure
		Number of		Amortized			Fair			Per Issuer
	U.S. State	Issuers		Cost			Value			(Fair Value)
		(dollars in thousands)
	Illinois	82		$	82,884		$	83,804		$	1,022
	Wisconsin	41		43,117			43,122			1,052
	Michigan	37		35,350			35,365			956
	Pennsylvania	11		14,132			14,133			1,285
	Ohio	12		11,709			11,426			952
	Texas	7		7,510			7,270			1,039
	Iowa	3		6,126			6,060			2,020
	Other	26		21,865			22,290			857
	Total general obligations bonds	219		$	222,693		$	223,470		$	1,020
Revenue bonds
Securities
Summary of amortized cost and fair values of the Company's portfolio of municipal bonds by issuer state
	December 31, 2014:
										Average Exposure
		Number of		Amortized			Fair			Per Issuer
	U.S. State	Issuers		Cost			Value			(Fair Value)
		(dollars in thousands)
	Illinois	4		$	6,772		$	6,708		$	1,677
	Indiana	8		12,520			12,469			1,559
	Other	21		18,721			18,685			890
	Total revenue bonds	33		$	38,013		$	37,862		$	1,147
	December 31, 2013:
										Average Exposure
		Number of		Amortized			Fair			Per Issuer
	U.S. State	Issuers		Cost			Value			(Fair Value)
		(dollars in thousands)
	Illinois	4		$	7,356		$	7,121		$	1,780
	Indiana	14		14,740			14,481			1,034
	Other	30		28,122			27,911			930
	Total revenue bonds	48		$	50,218		$	49,513		$	1,032

Loans_Tables

Loans (Tables)	12 Months Ended
	Dec. 31, 2014
Loans
Schedule of geographic distributions of loans
		December 31, 2014
		Illinois			Florida			Indiana			Total
		(dollars in thousands)
	Commercial	$	554,779		$	16,739		$	30,242		$	601,760
	Commercial real estate	811,034			171,243			121,874			1,104,151
	Real estate construction	60,994			17,950			28,110			107,054
	Retail real estate	473,171			106,658			12,644			592,473
	Retail other	9,690			562			—			10,252
	Total	$	1,909,668		$	313,152		$	192,870		$	2,415,690
	Less held for sale(1)										10,400
											$	2,405,290
	Less allowance for loan losses										47,453
	Net loans										$	2,357,837
	(1) Loans held for sale are included in retail real estate.
		December 31, 2013
		Illinois			Florida			Indiana			Total
		(dollars in thousands)
	Commercial	$	530,174		$	20,536		$	29,902		$	580,612
	Commercial real estate	800,568			160,255			131,450			1,092,273
	Real estate construction	55,190			17,426			6,239			78,855
	Retail real estate	419,801			103,104			11,588			534,493
	Retail other	8,422			552			93			9,067
	Total	$	1,814,155		$	301,873		$	179,272		$	2,295,300
	Less held for sale(1)										13,840
											$	2,281,460
	Less allowance for loan losses										47,567
	Net loans										$	2,233,893
	(1) Loans held for sale are included in retail real estate.
Schedule of weighted average risk grades segregated by category of loans (excluding held-for-sale, non posted and clearings) and geography
		December 31, 2014
		Weighted Avg.		Grades			Grade			Grade			Grade			Grade
		Risk Grade		1, 3, 6			7			8			9			10
		(dollars in thousands)
	Illinois/Indiana
	Commercial	4.80		$	542,796		$	27,032		$	8,549		$	5,498		$	1,146
	Commercial real estate	5.67		819,708			64,975			25,719			19,821			2,685
	Real estate construction	5.91		71,074			5,332			11,448			1,204			46
	Retail real estate	3.46		453,560			10,478			4,569			3,179			1,414
	Retail other	3.21		9,632			26			24			—			8
	Total Illinois/Indiana			$	1,896,770		$	107,843		$	50,309		$	29,702		$	5,299
	Florida
	Commercial	5.40		$	13,455		$	105		$	78		$	1,459		$	1,642
	Commercial real estate	6.00		123,807			25,520			6,002			15,404			510
	Real estate construction	6.21		16,475			—			615			842			18
	Retail real estate	4.09		82,185			11,686			9,601			1,031			1,531
	Retail other	2.94		562			—			—			—			—
	Total Florida			$	236,484		$	37,311		$	16,296		$	18,736		$	3,701
	Total			$	2,133,254		$	145,154		$	66,605		$	48,438		$	9,000
		December 31, 2013
		Weighted Avg.		Grades			Grade			Grade			Grade			Grade
		Risk Grade		1, 3, 6			7			8			9			10
		(dollars in thousands)
	Illinois/Indiana
	Commercial	4.66		$	487,587		$	46,992		$	15,986		$	8,536		$	975
	Commercial real estate	5.55		799,117			79,371			19,327			29,606			4,597
	Real estate construction	7.11		21,585			16,376			11,920			7,686			3,862
	Retail real estate	3.53		393,299			9,285			5,392			4,408			3,936
	Retail other	2.64		8,451			60			—			4			—
	Total Illinois/Indiana			$	1,710,039		$	152,084		$	52,625		$	50,240		$	13,370
	Florida
	Commercial	5.89		$	16,460		$	174		$	3,218		$	684		$	—
	Commercial real estate	6.02		116,741			16,470			11,250			12,721			3,073
	Real estate construction	6.64		7,886			7,961			743			836			—
	Retail real estate	3.85		77,116			12,052			9,417			3,050			721
	Retail other	1.72		552			—			—			—			—
	Total Florida			$	218,755		$	36,657		$	24,628		$	17,291		$	3,794
	Total			$	1,928,794		$	188,741		$	77,253		$	67,531		$	17,164
Schedule of age analysis of past due loans still accruing and non-accrual loans
		December 31, 2014
		Loans past due, still accruing									Non-accrual
		30-59 Days			60-89 Days			90+Days			Loans
		(dollars in thousands)
	Illinois/Indiana
	Commercial	$	15		$	105		$	—		$	1,146
	Commercial real estate	1,068			—			10			2,685
	Real estate construction	—			—			—			46
	Retail real estate	488			128			—			1,414
	Retail other	15			—			—			8
	Total Illinois/Indiana	$	1,586		$	233		$	10		$	5,299
	Florida
	Commercial	$	—		$	—		$	—		$	1,642
	Commercial real estate	—			—			—			510
	Real estate construction	—			—			—			18
	Retail real estate	—			—			—			1,531
	Retail other	—			—			—			—
	Total Florida	$	—		$	—		$	—		$	3,701
	Total	$	1,586		$	233		$	10		$	9,000
		December 31, 2013
		Loans past due, still accruing									Non-accrual
		30-59 Days			60-89 Days			90+Days			Loans
		(dollars in thousands)
	Illinois/Indiana
	Commercial	$	906		$	279		$	92		$	975
	Commercial real estate	567			3,736			—			4,597
	Real estate construction	—			—			—			3,862
	Retail real estate	483			123			103			3,936
	Retail other	20			—			—			—
	Total Illinois/Indiana	$	1,976		$	4,138		$	195		$	13,370
	Florida
	Commercial	$	—		$	—		$	—		$	—
	Commercial real estate	—			—			—			3,073
	Real estate construction	—			—			—			—
	Retail real estate	—			—			—			721
	Retail other	—			—			—			—
	Total Florida	$	—		$	—		$	—		$	3,794
	Total	$	1,976		$	4,138		$	195		$	17,164
Summary of restructured loans
		December 31,			December 31,
		2014			2013
		(dollars in thousands)
	Restructured loans:
	In compliance with modified terms	$	11,866		$	11,511
	30 – 89 days past due	—			380
	Included in non-performing loans	1,126			5,919
	Total	$	12,992		$	17,810
Schedule of details of impaired loans, segregated by category and geography
		December 31, 2014
		Unpaid			Recorded			Recorded			Total			Related			Average
		Contractual			Investment			Investment			Recorded			Allowance			Recorded
		Principal			with No			with Allowance			Investment						Investment
		Balance			Allowance
		(dollars in thousands)
	Illinois/Indiana
	Commercial	$	2,944		$	1,376		$	741		$	2,117		$	595		$	2,479
	Commercial real estate	4,007			1,140			2,854			3,994			1,975			5,473
	Real estate construction	46			—			46			46			46			2,269
	Retail real estate	2,794			2,403			25			2,428			25			3,061
	Retail other	8			8			—			8			—			2
	Total Illinois/Indiana	$	9,799		$	4,927		$	3,666		$	8,593		$	2,641		$	13,284
	Florida
	Commercial	$	2,742		$	1,642		$	—		$	1,642		$	—		$	330
	Commercial real estate	5,775			4,414			1,274			5,688			370			5,032
	Real estate construction	620			551			—			551			—			485
	Retail real estate	11,181			9,755			350			10,105			150			9,532
	Retail other	7			—			7			7			7			5
	Total Florida	$	20,325		$	16,362		$	1,631		$	17,993		$	527		$	15,384
	Total	$	30,124		$	21,289		$	5,297		$	26,586		$	3,168		$	28,668
		December 31, 2013
		Unpaid			Recorded			Recorded			Total			Related			Average
		Contractual			Investment			Investment			Recorded			Allowance			Recorded
		Principal			with No			with Allowance			Investment						Investment
		Balance			Allowance
		(dollars in thousands)
	Illinois/Indiana
	Commercial	$	2,825		$	1,684		$	602		$	2,286		$	485		$	4,169
	Commercial real estate	8,866			3,671			3,740			7,411			1,977			10,335
	Real estate construction	4,932			2,292			1,570			3,862			468			5,889
	Retail real estate	5,583			3,267			2,010			5,277			604			5,296
	Retail other	—			—			—			—			—			—
	Total Illinois/Indiana	$	22,206		$	10,914		$	7,922		$	18,836		$	3,534		$	25,689
	Florida
	Commercial	$	—		$	—		$	—		$	—		$	—		$	—
	Commercial real estate	7,108			3,946			1,319			5,265			416			6,662
	Real estate construction	417			417			—			417			—			1,294
	Retail real estate	10,346			9,005			537			9,542			337			11,079
	Retail other	—			—			—			—			—			—
	Total Florida	$	17,871		$	13,368		$	1,856		$	15,224		$	753		$	19,035
	Total	$	40,077		$	24,282		$	9,778		$	34,060		$	4,287		$	44,724
Schedule of changes in the allowance for loan losses
		Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Balance, beginning of year	$	47,567		$	48,012		$	58,506
	Provision for loan losses	2,000			7,500			16,500
	Loan balances charged-off	(7,371		)	(10,669		)	(30,063		)
	Recoveries applicable to loan balances previously charged-off	5,257			2,724			3,069
	Balance, end of year	$	47,453		$	47,567		$	48,012
Schedule of activity on the allowance for loan losses
		Year Ended December 31, 2014
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
	Illinois/Indiana
	Beginning balance	$	8,452		$	16,379		$	2,540		$	6,862		$	216		$	34,449
	Provision for loan loss	1,048			(880		)	90			5,942			332			6,532
	Charged-off	(864		)	(1,173		)	(657		)	(2,396		)	(429		)	(5,519		)
	Recoveries	233			2,108			617			337			185			3,480
	Ending Balance	$	8,869		$	16,434		$	2,590		$	10,745		$	304		$	38,942
	Florida
	Beginning balance	$	1,926		$	5,733		$	1,168		$	4,287		$	4		$	13,118
	Provision for loan loss	195			(1,799		)	(1,889		)	(1,021		)	(18		)	(4,532		)
	Charged-off	(1,126		)	—			(69		)	(656		)	(1		)	(1,852		)
	Recoveries	177			271			995			307			27			1,777
	Ending Balance	$	1,172		$	4,205		$	205		$	2,917		$	12		$	8,511
		Year Ended December 31, 2013
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
	Illinois/Indiana
	Beginning balance	$	6,597		$	15,023		$	2,527		$	8,110		$	322		$	32,579
	Provision for loan loss	2,681			2,143			847			616			63			6,350
	Charged-off	(964		)	(1,361		)	(1,212		)	(2,187		)	(511		)	(6,235		)
	Recoveries	138			574			378			323			342			1,755
	Ending Balance	$	8,452		$	16,379		$	2,540		$	6,862		$	216		$	34,449
	Florida
	Beginning balance	$	1,437		$	6,062		$	2,315		$	5,614		$	5		$	15,433
	Provision for loan loss	414			2,225			(1,419		)	(51		)	(19		)	1,150
	Charged-off	—			(2,543		)	(56		)	(1,828		)	(7		)	(4,434		)
	Recoveries	75			(11		)	328			552			25			969
	Ending Balance	$	1,926		$	5,733		$	1,168		$	4,287		$	4		$	13,118
		Year Ended December 31, 2012
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
	Illinois/Indiana
	Beginning balance	$	9,143		$	18,605		$	4,352		$	6,473		$	464		$	39,037
	Provision for loan loss	1,428			10,058			(270		)	4,397			278			15,891
	Charged-off	(4,176		)	(14,016		)	(1,883		)	(3,264		)	(636		)	(23,975		)
	Recoveries	202			376			328			504			216			1,626
	Ending Balance	$	6,597		$	15,023		$	2,527		$	8,110		$	322		$	32,579
	Florida
	Beginning balance	$	1,939		$	8,413		$	2,936		$	6,160		$	21		$	19,469
	Provision for loan loss	(811		)	(619		)	(555		)	2,626			(32		)	609
	Charged-off	(246		)	(1,858		)	(336		)	(3,646		)	(2		)	(6,088		)
	Recoveries	555			126			270			474			18			1,443
	Ending Balance	$	1,437		$	6,062		$	2,315		$	5,614		$	5		$	15,433
Schedule of allowance for loan losses and recorded investments in loans by category and geography
		As of December 31, 2014
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
	Illinois/Indiana
	Amount allocated to:
	Loans individually evaluated for impairment	$	595		$	1,975		$	46		$	25		$	—		$	2,641
	Loans collectively evaluated for impairment	8,274			14,459			2,544			10,720			304			36,301
	Ending Balance	$	8,869		$	16,434		$	2,590		$	10,745		$	304		$	38,942
	Loans:
	Loans individually evaluated for impairment	$	2,117		$	3,994		$	46		$	2,428		$	8		$	8,593
	Loans collectively evaluated for impairment	582,904			928,914			89,058			473,611			9,682			2,084,169
	Ending Balance	$	585,021		$	932,908		$	89,104		$	476,039		$	9,690		$	2,092,762
	Florida
	Amount allocated to:
	Loans individually evaluated for impairment	$	—		$	370		$	—		$	150		$	7		$	527
	Loans collectively evaluated for impairment	1,172			3,835			205			2,767			5			7,984
	Ending Balance	$	1,172		$	4,205		$	205		$	2,917		$	12		$	8,511
	Loans:
	Loans individually evaluated for impairment	$	1,642		$	5,688		$	551		$	10,105		$	7		$	17,993
	Loans collectively evaluated for impairment	15,097			165,555			17,399			95,929			555			294,535
	Ending Balance	$	16,739		$	171,243		$	17,950		$	106,034		$	562		$	312,528
		As of December 31, 2013
		Commercial			Commercial			Real Estate			Retail Real			Retail Other			Total
					Real Estate			Construction			Estate
		(dollars in thousands)
	Illinois/Indiana
	Amount allocated to:
	Loans individually evaluated for impairment	$	485		$	1,977		$	468		$	604		$	—		$	3,534
	Loans collectively evaluated for impairment	7,967			14,402			2,072			6,258			216			30,915
	Ending Balance	$	8,452		$	16,379		$	2,540		$	6,862		$	216		$	34,449
	Loans:
	Loans individually evaluated for impairment	$	2,286		$	7,411		$	3,862		$	5,277		$	—		$	18,836
	Loans collectively evaluated for impairment	557,790			924,607			57,567			413,020			8,515			1,961,499
	Ending Balance	$	560,076		$	932,018		$	61,429		$	418,297		$	8,515		$	1,980,335
	Florida
	Amount allocated to:
	Loans individually evaluated for impairment	$	—		$	416		$	—		$	337		$	—		$	753
	Loans collectively evaluated for impairment	1,926			5,317			1,168			3,950			4			12,365
	Ending Balance	$	1,926		$	5,733		$	1,168		$	4,287		$	4		$	13,118
	Loans:
	Loans individually evaluated for impairment	$	—		$	5,265		$	417		$	9,542		$	—		$	15,224
	Loans collectively evaluated for impairment	20,536			154,990			17,009			92,814			552			285,901
	Ending Balance	$	20,536		$	160,255		$	17,426		$	102,356		$	552		$	301,125

Loan_Servicing_Tables

Loan Servicing (Tables)	12 Months Ended
	Dec. 31, 2014
Loan Servicing
Summary of mortgage servicing rights capitalized and amortized
		For the Years Ended December 31,
		2014		2013		2012
		(dollars in thousands)
	Mortgage servicing rights capitalized	$	983	$	2,490	$	2,794
	Mortgage servicing rights amortized	$	2,228	$	2,650	$	2,972

Premises_and_Equipment_Tables

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2014
Premises and Equipment
Summary of premises and equipment
		December 31,
		2014		2013
		(dollars in thousands)
	Land and improvements	$	21,559	$	21,532
	Buildings and improvements	62,794		62,159
	Furniture and equipment	32,018		33,622
		116,371		117,313
	Less accumulated depreciation	52,397		51,486
	Total premises and equipment	$	63,974	$	65,827

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Other Intangible Assets
Schedule of carrying amount of goodwill by operating segment	The carrying amount of goodwill by operating segment, in thousands, at December 31, 2014 and 2013 is as follows:
	Goodwill:
	FirsTech	$	8,992
	Busey Wealth Management	11,694
	Total Goodwill	$	20,686
Schedule of other intangible asset disclosures
		Balance at		Amortization		Balance at
		December 31,				December 31,
		2013				2014
		(dollars in thousands)
	Amortized intangible assets:
	Core deposit intangible assets	$	6,124	$	1,870	$	4,254
	Customer relationship intangible assets	3,447		1,014		2,433
		$	9,571	$	2,884	$	6,687
Schedule of carrying amount of amortized intangible assets
		Core deposit		Customer
		intangible		relationship
				intangible
		(dollars in thousands)
	As of December 31, 2014:
	Gross carrying amount	$	19,962	$	11,320
	Accumulated amortization	15,708		8,887
		$	4,254	$	2,433
	Estimated amortization expense on balance at December 31, 2014:
	2015	$	1,719	$	972
	2016	1,644		929
	2017	891		532
		$	4,254	$	2,433

Deposits_Tables

Deposits (Tables)	12 Months Ended
	Dec. 31, 2014
Deposits
Schedule of composition of deposits
		December 31,
		2014		2013
		(dollars in thousands)
	Demand deposits, non-interest-bearing	$	666,607	$	547,531
	Interest-bearing transaction deposits	67,774		61,384
	Savings deposits	210,673		206,587
	Money market deposits	1,459,723		1,471,265
	Time deposits	496,071		582,371
	Total	$	2,900,848	$	2,869,138
Schedule of maturities of time deposits
	As of December 31, 2014, the scheduled maturities of time deposits, in thousands, are as follows:
	2015	$	309,598
	2016	95,118
	2017	61,161
	2018	18,934
	2019	11,250
	Thereafter	10
		$	496,071

Federal_Funds_Purchased_and_Se1

Federal Funds Purchased and Securities Sold Under Agreements to Repurchase (Tables)	12 Months Ended
	Dec. 31, 2014
Federal Funds Purchased and Securities Sold Under Agreements to Repurchase
Schedule of distribution of securities sold under agreements to repurchase and weighted average interest rates
		December 31,
		2014			2013
		(dollars in thousands)
	Balance	$	198,893		$	172,348
	Weighted average interest rate at end of period	0.14		%	0.13		%
	Maximum outstanding at any month end	$	198,893		$	172,348
	Average daily balance	$	148,452		$	137,777
	Weighted average interest rate during period (1)	0.12		%	0.14		%
	(1) The weighted average interest rate is computed by dividing total interest for the period by the average daily balance outstanding.

Longterm_Debt_Tables

Long-term Debt (Tables)	12 Months Ended
	Dec. 31, 2014
Long-term Debt
Summary of long-term debt
		December 31,
		2014		2013
		(dollars in thousands)
	Notes payable, FHLB, ranging in maturity from five to ten years, collateralized by FHLB deposits, residential and commercial real estate loans and FHLB stock.	$	50,000	$	—

Junior_Subordinated_Debt_Owed_1

Junior Subordinated Debt Owed to Unconsolidated Trusts (Tables)	12 Months Ended
	Dec. 31, 2014
Junior Subordinated Debt Owed to Unconsolidated Trusts
Summary of the outstanding junior subordinated notes and the related trust preferred securities issued by each trust
	The table below summarizes the outstanding junior subordinated notes and the related trust preferred securities issued by each trust as of December 31, 2014:
		First Busey Statutory Trust II	First Busey Statutory Trust III	First Busey Statutory Trust IV
	Junior Subordinated Notes:
	Principal balance	$15,000,000	$10,000,000	$30,000,000
	Annual interest rate(1)	3-mo LIBOR + 2.65%	3-mo LIBOR + 1.75%	3-mo LIBOR + 1.55%
	Stated maturity date	June 17, 2034	June 15, 2035	June 15, 2036
	Trust Preferred Securities:
	Face value	$15,000,000	$10,000,000	$30,000,000
	Annual distribution rate(1)	3-mo LIBOR + 2.65%	3-mo LIBOR + 1.75%	3-mo LIBOR + 1.55%
	Issuance date	April 30, 2004	June 15, 2005	June 15, 2006
	Distribution dates(2)	Quarterly	Quarterly	Quarterly
	(1) First Busey Statutory Trust IV maintained a 5-year fixed coupon of 6.94% through June 10, 2011, subsequently converting to a floating 3-month LIBOR +1.55%.
	(2) All cash distributions are cumulative.

Capital_Tables

Capital (Tables)	12 Months Ended
	Dec. 31, 2014
Capital
Schedule of capital adequacy requirements
						Minimum				Minimum
						Capital				To Be Well
		Actual				Requirement				Capitalized
		Amount		Ratio		Amount		Ratio		Amount		Ratio
		(dollars in thousands)
	As of December 31, 2014:
	Total Capital (to Risk Weighted Assets)
	Consolidated	$	488,908	18.66	%	$	209,554	8.00	%	$	261,942	10.00	%
	Busey Bank	$	388,479	14.94	%	$	207,991	8.00	%	$	259,988	10.00	%
	Tier 1 Capital (to Risk Weighted Assets)
	Consolidated	$	455,354	17.38	%	$	104,777	4.00	%	$	157,166	6.00	%
	Busey Bank	$	355,166	13.66	%	$	103,996	4.00	%	$	155,993	6.00	%
	Tier 1 Capital (to Average Assets)
	Consolidated	$	455,354	12.79	%	$	142,401	4.00	%	N/A		N/A
	Busey Bank	$	355,166	10.10	%	$	140,677	4.00	%	$	175,846	5.00	%
	As of December 31, 2013:
	Total Capital (to Risk Weighted Assets)
	Consolidated	$	449,407	18.21	%	$	197,422	8.00	%	$	246,777	10.00	%
	Busey Bank	$	396,248	16.17	%	$	196,002	8.00	%	$	245,002	10.00	%
	Tier 1 Capital (to Risk Weighted Assets)
	Consolidated	$	417,564	16.92	%	$	98,711	4.00	%	$	148,067	6.00	%
	Busey Bank	$	364,625	14.88	%	$	98,001	4.00	%	$	147,001	6.00	%
	Tier 1 Capital (to Average Assets)
	Consolidated	$	417,564	12.02	%	$	138,896	4.00	%	N/A		N/A
	Busey Bank	$	364,625	10.66	%	$	136,818	4.00	%	$	171,023	5.00	%

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Taxes
Schedule of the components of income taxes
		Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Current	$	4,830		$	4,020		$	1,926
	Deferred	12,704			10,091			8,571
	Total income tax expense	$	17,534		$	14,111		$	10,497
Schedule of the reconciliation of federal and state income taxes at statutory rates to the income taxes included in the statements of income
		Years Ended December 31,
		2014		2013		2012
		% of		% of		% of
		Pretax		Pretax		Pretax
		Income		Income		Loss
	Income tax at statutory rate	35.0	%	35.0	%	35.0	%
	Effect of:
	Tax-exempt interest, net	(2.6	)%	(3.5	)%	(4.5	)%
	State income taxes, net	5.7	%	4.5	%	3.5	%
	Income on bank owned life insurance	(1.0	)%	(0.9	)%	(1.8	)%
	Other, net	(2.2	)%	(2.2	)%	(0.3	)%
		34.9	%	32.9	%	31.9	%
Schedule of the deferred tax assets and liabilities
		2014			2013
		(dollars in thousands)
	Deferred tax assets:
	Allowance for loan losses	$	18,904		$	19,416
	Stock-based compensation	1,472			1,319
	Loan adjustments	94			108
	Deferred compensation	2,057			2,015
	Accrued vacation	527			545
	Employee costs	656			1,264
	Other	2,498			1,780
		$	26,208		$	26,447
	Deferred tax liabilities:
	Investment securities:
	Unrealized gains on securities available for sale	$	(3,884	)	$	(3,119	)
	Other	(1,997		)	(2,450		)
	Basis in premises and equipment	(2,012		)	(2,590		)
	Mortgage servicing assets	(1,549		)	(2,097		)
	Basis in core deposit and customer intangible assets	(2,669		)	(3,908		)
	Deferred loan origination costs	(257		)	(20		)
		$	(12,368	)	$	(14,184	)
	Net operating loss carryforward, net of valuation allowance	8,333			23,379
	Net deferred tax assets	$	22,173		$	35,642

Employee_Benefit_Plans_Tables

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Employee Benefit Plans
Schedule of expenses related to the employee benefit plans
		Years Ended December 31,
		2014		2013		2012
		(dollars in thousands)
	Employee benefits	$	2,636	$	2,975	$	3,024
	Interest on employee stock ownership plan debt	—		—		5
	Total employer contributions	$	2,636	$	2,975	$	3,029

Stock_Incentive_Plans_Tables

Stock Incentive Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Stock Incentive Plans
Schedule of status and changes in stock option plans
			2014					2013					2012
					Weighted-					Weighted-					Weighted-
					Average					Average					Average
					Exercise					Exercise					Exercise
			Shares		Price			Shares		Price			Shares		Price
	Outstanding at beginning of year		696,379		$	17.22		857,468		$	17.01		1,017,922		$	16.23
	Granted		—		—			—		—			—		—
	Exercised		—		—			—		—			—		—
	Forfeited		(186,249	)	19.67			(161,089	)	16.1			(160,454	)	12.07
	Outstanding at end of year		510,130		$	16.33		696,379		$	17.22		857,468		$	17.01
	Exercisable at end of year		510,130		$	16.33		696,379		$	17.22		857,468		$	17.01
Summary of stock options outstanding by range of exercise prices	The following table summarizes information about stock options outstanding at December 31, 2014:
														Options
				Options Outstanding										Exercisable
									Weighted-
						Weighted-			Average
	Range of					Average			Remaining
	Exercise					Exercise			Contractual		Intrinsic					Intrinsic
	Prices			Number		Price			Life		Value			Number		Value
	$	4.49-7.53		105,000		$	6.01		5.00					105,000
	17.12-19.55			405,130		19.00			0.86					405,130
				510,130		$	16.33		1.71		$	106		510,130		$	106
Summary of the changes in stock awards (restricted stock units)
			2014					2013					2012
					Weighted-					Weighted-					Weighted-
					Average					Average					Average
					Grant Date					Grant Date					Grant Date
			Shares		Fair Value			Shares		Fair Value			Shares		Fair Value
	Outstanding at beginning of year		919,928		$	4.97		736,412		$	4.92		455,352		$	4.98
	Reclass to DSUs		(4,960	)	5.04			—		—			—		—
	Granted		304,277		5.84			351,452		5.02			266,258		4.83
	Dividend equivalents earned		35,166		5.62			17,211		4.86			32,704		4.79
	Vested		(26,432	)	4.82			(156,795	)	4.84			(9,925	)	4.19
	Forfeited		(44,109	)	4.73			(28,352	)	5.14			(7,977	)	5.15
	Outstanding at end of year		1,183,870		$	5.22		919,928		$	4.97		736,412		$	4.92
Summary of the changes in the company's stock unit awards
			2014					2013					2012
					Weighted-					Weighted-					Weighted-
					Average					Average					Average
					Grant Date					Grant Date					Grant Date
			Shares		Fair Value			Shares		Fair Value			Shares		Fair Value
	Non-vested at beginning of year		29,054		$	5.05		32,991		$	4.77		22,771		$	5.23
	Reclass from RSUs		4,960		5.04			—		—			—		—
	Granted		49,699		5.84			28,800		5.04			31,897		4.77
	Dividend equivalents earned		4,042		5.63			1,636		5.03			2,252		4.76
	Vested		(32,011	)	5.1			(34,373	)	4.77			(23,929	)	5.21
	Forfeited		—		—			—		—			—		—
	Non-vested at end of year		55,745		$	5.77		29,054		$	5.05		32,991		$	4.77
	Outstanding at end of year		146,057		$	5.34		87,356		$	5.06		56,920		$	4.96

Transactions_with_Directors_an1

Transactions with Directors and Executive Officers (Tables)	12 Months Ended
	Dec. 31, 2014
Transactions with Directors and Executive Officers
Schedule of the analysis of the changes in loans to related parties
	The following is an analysis of the changes in loans, in thousands, to related parties during the year ended December 31, 2014:
	Balance at beginning of year	$	30,105
	Addition due to change in relationship	8,393
	Deletion due to change in relationship	(40		)
	New loans/ advances	50,576
	Repayments	(51,584		)
	Balance at end of year	$	37,450

Commitments_Contingencies_and_1

Commitments, Contingencies and Credit Risk (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments, Contingencies and Credit Risk
Schedule of contractual amount of exposure to off-balance-sheet risk
		December 31,
		2014		2013
		(dollars in thousands)
	Financial instruments whose contract amounts represent credit risk:
	Commitments to extend credit	$	561,439	$	527,614
	Standby letters of credit	20,466		10,155
Schedule of projected minimum rental payments under the terms of the leases
	The projected minimum rental payments under the terms of the leases at December 31, 2014 in thousands, are as follows:
	2015	$	941
	2016	219
	2017	111
	2018	102
	2019	70
		$	1,443

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Financial Instruments
Schedule of notional amount and fair values of open foreign currency forward contracts
		December 31, 2014		December 31, 2013
		(dollars in thousands)
	Forward contracts — foreign exchange:
	Notional amount	$	1,781	$	—
	Other assets — estimated fair value	15		—

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Measurements
Schedule of financial assets and financial liabilities measured at fair value on a recurring basis
		Level 1		Level 2			Level 3		Total
		Inputs		Inputs			Inputs		Fair Value
		(dollars in thousands)
	December 31, 2014
	Securities available for sale
	U.S. Treasury securities	$	—	$	50,606		$	—	$	50,606
	Obligations of U.S. government corporations and agencies	—		167,010			—		167,010
	Obligations of states and political subdivisions	—		220,161			—		220,161
	Residential mortgage-backed securities	—		235,636			—		235,636
	Corporate debt securities	—		79,307			—		79,307
	Mutual funds and other equity securities	6,345		—			—		6,345
	Derivative assets
	Foreign currency forward contracts	—		15			—		15
	December 31, 2013
	Securities available for sale
	U.S. Treasury securities	$	—	$	102,640		$	—	$	102,640
	Obligations of U.S. government corporations and agencies	—		257,411			—		257,411
	Obligations of states and political subdivisions	—		272,152			—		272,152
	Residential mortgage-backed Securities	—		177,735			—		177,735
	Corporate debt securities	—		25,506			—		25,506
	Mutual funds and other equity securities	5,866		—			—		5,866
Schedule of assets and liabilities measured at fair value on a non-recurring basis
		Level 1		Level 2			Level 3		Total
		Inputs		Inputs			Inputs		Fair Value
		(dollars in thousands)
	December 31, 2014
	Impaired loans	$	—	$	—		$	2,129	$	2,129
	December 31, 2013
	Impaired loans	$	—	$	—		$	5,491	$	5,491
	OREO	—		—			1,134		1,134
Schedule of quantitative information about Level 3 fair value measurements
		Quantitative Information about Level 3 Fair Value Measurements
		Fair Value		Valuation		Unobservable		Range
		Estimate		Techniques		Input		(Weighted Average)
		(dollars in thousands)
	December 31, 2014
	Impaired loans	$	2,129	Appraisal of collateral		Appraisal adjustments		-7.7% to -100.0%
								(-54.3%)
	December 31, 2013
	Impaired loans	$	5,491	Appraisal of collateral		Appraisal adjustments		-0.4% to -100.0%
								(-36.0%)
	OREO	1,134		Appraisal of collateral		Appraisal adjustments		-6.6% to -100.0%
								(-47.9%)
Schedule of estimated fair values of financial instruments
		December 31, 2014					December 31, 2013
		Carrying		Fair			Carrying		Fair
		Amount		Value			Amount		Value
		(dollars in thousands)
	Financial assets:
	Level 2 inputs:
	Cash and due from banks	$	339,438	$	339,438		$	231,603	$	231,603
	Securities held to maturity	2,373		2,425			834		831
	Loans held for sale	10,400		10,634			13,840		14,103
	Accrued interest receivable	11,187		11,187			11,148		11,148
	Level 3 inputs:
	Loans, net	2,357,837		2,360,000			2,233,893		2,236,841
	Financial liabilities:
	Level 2 inputs:
	Deposits	$	2,900,848	$	2,900,763		$	2,869,138	$	2,870,870
	Securities sold under agreements to repurchase	198,893		198,893			172,348		172,348
	Long-term debt	50,000		50,000			—		—
	Junior subordinated debt owed to unconsolidated trusts	55,000		55,000			55,000		55,000
	Accrued interest payable	507		507			673		673

Reportable_Segments_and_Relate1

Reportable Segments and Related Information (Tables)	12 Months Ended
	Dec. 31, 2014
Reportable Segments and Related Information
Summary of information relating to reportable segments
		Goodwill						Total Assets
		2014			2013			2014			2013
		(dollars in thousands)						(dollars in thousands)
	As of December 31,
	Busey Bank	$	—		$	—		$	3,589,419		$	3,456,555
	FirsTech	8,992			8,992			28,540			27,253
	Busey Wealth Management	11,694			11,694			31,196			28,548
	All Other	—			—			16,452			27,219
	Totals	$	20,686		$	20,686		$	3,665,607		$	3,539,575
		Year ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Interest Income:
	Busey Bank	$	107,766		$	108,413		$	116,608
	FirsTech	52			51			62
	Busey Wealth Management	287			242			251
	All Other	(30		)	(10		)	(5		)
	Total interest income	$	108,075		$	108,696		$	116,916
	Interest Expense:
	Busey Bank	$	5,355		$	7,448		$	13,466
	FirsTech	—			—			—
	Busey Wealth Management	—			—			—
	All Other	1,144			1,183			1,304
	Total interest expense	$	6,499		$	8,631		$	14,770
	Other Income:
	Busey Bank	$	32,452		$	36,774		$	39,908
	FirsTech	9,561			8,541			8,522
	Busey Wealth Management	18,953			17,799			16,345
	All Other	(2,025		)	(531		)	2,077
	Total other income	$	58,941		$	62,583		$	66,852
	Net Income:
	Busey Bank	$	30,764		$	25,416		$	19,162
	FirsTech	1,227			1,000			935
	Busey Wealth Management	4,681			4,242			3,363
	All Other	(3,898		)	(1,932		)	(1,103		)
	Total net income	$	32,774		$	28,726		$	22,357

Parent_Company_Only_Financial_1

Parent Company Only Financial Information (Tables) (Parent)	12 Months Ended
	Dec. 31, 2014
Parent
Parent Company Only Financial Information
Balance Sheet
	BALANCE SHEETS
		December 31,
		2014			2013
		(dollars in thousands)
	ASSETS
	Cash and due from subsidiary banks	$	84,537		$	42,645
	Securities available for sale	201			201
	Investments in subsidiaries:
	Bank	373,773			400,442
	Non-bank	28,348			25,646
	Premises and equipment, net	523			521
	Other assets	8,684			9,450
	Total assets	$	496,066		$	478,905
	LIABILITIES AND STOCKHOLDERS’ EQUITY
	Liabilities:
	Junior subordinated debentures owed to unconsolidated
	Trusts	$	55,000		$	55,000
	Other liabilities	7,427			8,541
	Total liabilities	62,427			63,541
	Total stockholders’ equity	433,639			415,364
	Total liabilities and stockholders’ equity	$	496,066		$	478,905
Statement of Operations
	STATEMENTS OF INCOME
		Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Operating income:
	Dividends from subsidiaries:
	Bank	$	—		$	—		$	—
	Non-bank	2,000			2,000			2,500
	Interest and dividend income	20			46			49
	Other income	3,475			4,669			6,231
	Total operating income	5,495			6,715			8,780
	Expense:
	Salaries and employee benefits	6,778			5,139			4,718
	Interest expense	1,183			1,220			1,351
	Operating expense	2,563			2,163			2,469
	Total expense	10,524			8,522			8,538
	(Loss) income before income tax benefit and distributions less than net income of subsidiaries	(5,029		)	(1,807		)	242
	Income tax benefit	3,131			1,875			1,155
	(Loss) income before distributions less than net income of subsidiaries	(1,898		)	68			1,397
	Distributions less than net income of subsidiaries:
	Bank	31,991			26,416			20,097
	Non-bank	2,681			2,242			863
	Net income	$	32,774		$	28,726		$	22,357
Statement of Cash Flows
	STATEMENTS OF CASH FLOWS
		Years Ended December 31,
		2014			2013			2012
		(dollars in thousands)
	Cash Flows from Operating Activities
	Net income	$	32,774		$	28,726		$	22,357
	Adjustments to reconcile net income to net cash provided by (used in) operating activities:
	Depreciation and amortization	112			100			98
	Distributions less than net income of subsidiaries	(34,672		)	(28,658		)	(20,960		)
	Stock-based compensation	1,187			1,079			991
	Fair value adjustment on employee stock ownership plan shares allocated	—			—			(322		)
	Changes in assets and liabilities:
	Decrease (increase) in other assets	951			(62		)	125
	(Decrease) increase in other liabilities	(1,077		)	381			1,435
	Net cash (used in) provided by operating activities	(725		)	1,566			3,724
	Cash Flows from Investing Activities
	Decrease in loans	—			68			95
	Proceeds from sales of premises and equipment	—			226			—
	Purchases of premises and equipment	(114		)	(90		)	(11		)
	Net cash (used in) provided by investing activities	(114		)	204			84
	Cash Flows from Financing Activities
	Proceeds from charter amendment with subsidiary bank	60,000			50,000			—
	Shares surrendered upon vesting of restricted stock units to cover tax obligations	(45		)	(237		)	—
	Cash dividends paid	(17,224		)	(14,040		)	(24,427		)
	Net cash provided by (used in) financing activities	42,731			35,723			(24,427		)
	Net increase (decrease) in cash and due from subsidiary banks	41,892			37,493			(20,619		)
	Cash and due from subsidiary banks, beginning	42,645			5,152			25,771
	Cash and due from subsidiary banks, ending	$	84,537		$	42,645		$	5,152

Unaudited_Interim_Financial_Da1

Unaudited Interim Financial Data (Tables)	12 Months Ended
	Dec. 31, 2014
Unaudited Interim Financial Data
Schedule reflecting the summarized quarterly data
		2014
		December 31		September 30		June 30		March 31
	Interest income	$	27,657	$	27,511	$	26,656	$	26,251
	Interest expense	1,570		1,600		1,635		1,694
	Net interest income	26,087		25,911		25,021		24,557
	Provision for loan losses	—		—		1,000		1,000
	Non-interest income	14,739		14,204		15,012		14,986
	Non-interest expense	28,470		26,298		26,823		26,618
	Income before income taxes	12,356		13,817		12,210		11,925
	Income taxes	4,763		4,708		4,025		4,038
	Net income	$	7,593	$	9,109	$	8,185	$	7,887
	Preferred stock dividends	182		182		181		182
	Net income available to common stockholders	$	7,411	$	8,927	$	8,004	$	7,705
	Basic earnings per share	$	0.08	$	0.10	$	0.09	$	0.09
	Diluted earnings per share	$	0.08	$	0.10	$	0.09	$	0.09
		2013
		December 31		September 30		June 30		March 31
	Interest income	$	26,885	$	27,236	$	27,460	$	27,115
	Interest expense	1,881		2,003		2,215		2,532
	Net interest income	25,004		25,233		25,245		24,583
	Provision for loan losses	1,500		2,000		2,000		2,000
	Non-interest income	14,529		15,630		15,783		16,641
	Non-interest expense	27,585		27,358		27,801		29,567
	Income before income taxes	10,448		11,505		11,227		9,657
	Income taxes	3,528		3,572		3,787		3,224
	Net income	$	6,920	$	7,933	$	7,440	$	6,433
	Preferred stock dividends	908		909		908		908
	Net income available to common stockholders	$	6,012	$	7,024	$	6,532	$	5,525
	Basic earnings per share	$	0.07	$	0.08	$	0.08	$	0.06
	Diluted earnings per share	$	0.07	$	0.08	$	0.08	$	0.06

Significant_Accounting_Policie3

Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Significant Accounting Policies
Assets under care	$5,200,000,000	$5,000,000,000
Maximum estimated economic life	5 years
Goodwill
Goodwill impairment	$0	$0
Maximum | Commercial
Premises and Equipment
Estimated Useful Life	3 years
Buildings and improvements | Minimum
Premises and Equipment
Estimated Useful Life	3 years
Buildings and improvements | Maximum
Premises and Equipment
Estimated Useful Life	40 years
Furniture and equipment | Minimum
Premises and Equipment
Estimated Useful Life	3 years
Furniture and equipment | Maximum
Premises and Equipment
Estimated Useful Life	10 years

Significant_Accounting_Policie4

Significant Accounting Policies (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	item
Income taxes
Valuation allowance	$0
Accruals for payments of interest and penalties	0	0
Compensation expense recognized	1,200,000	1,100,000	1,000,000
Segment disclosure
Number of primary operating subsidiaries that are entity's segments	3
Herget Financial and Herget Bank
Business Acquisition
Business acquisition expenses	400,000
Restricted stock units
Income taxes
Compensation expense recognized	$0
Restricted stock units | Minimum
Income taxes
Requisite service period	1 year
Restricted stock units | Maximum
Income taxes
Requisite service period	5 years

Significant_Accounting_Policie5

Significant Accounting Policies (Details 3) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net income per share calculations for basic and diluted methods
Net income available to common stockholders (in dollars)	$7,411	$8,927	$8,004	$7,705	$6,012	$7,024	$6,532	$5,525	$32,047	$25,093	$18,724
Shares:
Weighted average common shares outstanding									86,906,000	86,765,000	86,643,000
Dilutive effect of outstanding options, warrants and restricted stock units as determined by the application of the treasury stock method (in shares)									386,000	299,000	9,000
Weighted average common shares outstanding, as adjusted for diluted earnings per share calculation									87,292,000	87,064,000	86,652,000
Basic earnings per common share (in dollars per share)	$0.08	$0.10	$0.09	$0.09	$0.07	$0.08	$0.08	$0.06	$0.37	$0.29	$0.22
Diluted earnings per common share (in dollars per share)	$0.08	$0.10	$0.09	$0.09	$0.07	$0.08	$0.08	$0.06	$0.37	$0.29	$0.22
Stock options
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)									457,630	643,879
Warrants
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)									573,833	573,833
Restricted stock units
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)									353,976	347,253

Cash_and_Due_from_Banks_Detail

Cash and Due from Banks (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Cash and Due from Banks
Required reserve balance	$12.30	$5.30

Securities_Details

Securities (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	item
Available for sale
Amortized Cost	$749,364,000	$833,735,000
Gross Unrealized Gains	10,740,000	11,350,000
Gross Unrealized Losses	-1,039,000	-3,775,000
Fair Value	759,065,000	841,310,000
Held to maturity
Amortized Cost	2,373,000	834,000
Gross Unrealized Gains	55,000	1,000
Gross Unrealized Losses	-3,000	-4,000
Fair Value	2,425,000	831,000
Available for sale, Amortized Cost
Due in one year or less	125,672,000
Due after one year through five years	347,781,000
Due after five years through ten years	120,891,000
Due after ten years	150,076,000
Amortized Cost	744,420,000
Available for sale, Fair Value
Due in one year or less	126,252,000
Due after one year through five years	349,168,000
Due after five years through ten years	124,483,000
Due after ten years	152,817,000
Fair Value	752,720,000
Held to maturity, Amortized Cost
Due in one year or less	72,000
Due after one year through five years	636,000
Due after five years through ten years	1,665,000
Amortized Cost	2,373,000	834,000
Held to maturity, Fair Value
Due in one year or less	72,000
Due after one year through five years	636,000
Due after five years through ten years	1,717,000
Fair Value	2,425,000	831,000
Realized gains and losses related to sales of securities available for sale
Gross security gains	807,000	599,000	1,602,000
Gross security (losses)	-31,000	-46,000	-5,000
Net security gains	776,000	553,000	1,597,000
Tax provision related to net realized gains (losses)	300,000	200,000	600,000
Carrying amount of investment securities pledged as collateral	536,200,000	428,700,000
Available for sale, Fair Value
Continuous unrealized losses existing for less than 12 months, gross	67,415,000	199,636,000
Continuous unrealized losses existing greater than 12 months, gross	65,898,000	8,492,000
Total	133,313,000	208,128,000
Available for sale, Unrealized Losses
Continuous unrealized losses existing for less than 12 months, gross	234,000	3,481,000
Continuous unrealized losses existing greater than 12 months, gross	805,000	294,000
Total	1,039,000	3,775,000
Held to maturity, Fair Value
Continuous unrealized losses existing for less than 12 months, gross	534,000	597,000
Total	534,000	597,000
Held to maturity, Unrealized Losses
Continuous unrealized losses existing for less than 12 months, gross	3,000	4,000
Total	3,000	4,000
Number of securities in unrealized loss position	202
Securities in unrealized loss position as a percentage of aggregate carrying value of investments	0.80%
Debt securities
Available for sale
Amortized Cost	744,420,000	829,621,000
Gross Unrealized Gains	9,339,000	9,598,000
Gross Unrealized Losses	-1,039,000	-3,775,000
Fair Value	752,720,000	835,444,000
U.S. Treasury securities
Available for sale
Amortized Cost	50,280,000	102,463,000
Gross Unrealized Gains	328,000	244,000
Gross Unrealized Losses	-2,000	-67,000
Fair Value	50,606,000	102,640,000
Available for sale, Fair Value
Continuous unrealized losses existing for less than 12 months, gross		25,830,000
Continuous unrealized losses existing greater than 12 months, gross	366,000
Total	366,000	25,830,000
Available for sale, Unrealized Losses
Continuous unrealized losses existing for less than 12 months, gross		67,000
Continuous unrealized losses existing greater than 12 months, gross	2,000
Total	2,000	67,000
Obligations of U.S. government corporations and agencies
Available for sale
Amortized Cost	166,207,000	254,998,000
Gross Unrealized Gains	981,000	2,741,000
Gross Unrealized Losses	-178,000	-328,000
Fair Value	167,010,000	257,411,000
Available for sale, Fair Value
Continuous unrealized losses existing for less than 12 months, gross		25,946,000
Continuous unrealized losses existing greater than 12 months, gross	25,118,000
Total	25,118,000	25,946,000
Available for sale, Unrealized Losses
Continuous unrealized losses existing for less than 12 months, gross		328,000
Continuous unrealized losses existing greater than 12 months, gross	178,000
Total	178,000	328,000
Obligations of states and political subdivisions
Available for sale
Amortized Cost	218,250,000	272,077,000
Gross Unrealized Gains	2,672,000	2,887,000
Gross Unrealized Losses	-761,000	-2,812,000
Fair Value	220,161,000	272,152,000
Held to maturity
Amortized Cost	1,359,000	834,000
Gross Unrealized Gains	15,000	1,000
Gross Unrealized Losses	-3,000	-4,000
Fair Value	1,371,000	831,000
Held to maturity, Amortized Cost
Amortized Cost	1,359,000	834,000
Held to maturity, Fair Value
Fair Value	1,371,000	831,000
Available for sale, Fair Value
Continuous unrealized losses existing for less than 12 months, gross	40,385,000	92,703,000
Continuous unrealized losses existing greater than 12 months, gross	40,201,000	8,492,000
Total	80,586,000	101,195,000
Available for sale, Unrealized Losses
Continuous unrealized losses existing for less than 12 months, gross	140,000	2,518,000
Continuous unrealized losses existing greater than 12 months, gross	621,000	294,000
Total	761,000	2,812,000
Held to maturity, Fair Value
Continuous unrealized losses existing for less than 12 months, gross	534,000	597,000
Total	534,000	597,000
Held to maturity, Unrealized Losses
Continuous unrealized losses existing for less than 12 months, gross	3,000	4,000
Total	3,000	4,000
Residential mortgage-backed securities
Available for sale
Amortized Cost	230,596,000	174,699,000
Gross Unrealized Gains	5,062,000	3,571,000
Gross Unrealized Losses	-22,000	-535,000
Fair Value	235,636,000	177,735,000
Available for sale, Fair Value
Continuous unrealized losses existing for less than 12 months, gross	10,630,000	53,543,000
Total	10,630,000	53,543,000
Available for sale, Unrealized Losses
Continuous unrealized losses existing for less than 12 months, gross	22,000	535,000
Total	22,000	535,000
Corporate debt securities
Available for sale
Amortized Cost	79,087,000	25,384,000
Gross Unrealized Gains	296,000	155,000
Gross Unrealized Losses	-76,000	-33,000
Fair Value	79,307,000	25,506,000
Available for sale, Fair Value
Continuous unrealized losses existing for less than 12 months, gross	16,400,000	1,614,000
Continuous unrealized losses existing greater than 12 months, gross	213,000
Total	16,613,000	1,614,000
Available for sale, Unrealized Losses
Continuous unrealized losses existing for less than 12 months, gross	72,000	33,000
Continuous unrealized losses existing greater than 12 months, gross	4,000
Total	76,000	33,000
Mutual funds and other equity securities
Available for sale
Amortized Cost	4,944,000	4,114,000
Gross Unrealized Gains	1,401,000	1,752,000
Fair Value	6,345,000	5,866,000
Commercial mortgage-backed securities
Held to maturity
Amortized Cost	1,014,000
Gross Unrealized Gains	40,000
Fair Value	1,054,000
Held to maturity, Amortized Cost
Amortized Cost	1,014,000
Held to maturity, Fair Value
Fair Value	$1,054,000

Securities_Details_2

Securities (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
	item	item
Securities
Available for sale, fair value	$759,065,000	$841,310,000
Held to maturity, fair value	2,425,000	831,000
General obligation bonds
Securities
Number of issuers	187	219
Amortized Cost	181,596,000	222,693,000
Fair Value	183,670,000	223,470,000
Average Exposure Per Issuer (Fair Value)	982,000	1,020,000
Amount of largest exposure to a single issuer	3,400,000	5,000,000
Percentage of the entity's stockholders equity in excess of aggregate book or market value	10.00%	10.00%
Percentage of underlying asset rated by at least a specified nationally recognized statistical rating organization	97.10%	96.40%
Minimum number of nationally recognized statistical rating organizations	1	1
Percentage of underlying asset unrated	2.90%	3.60%
General obligation bonds | Illinois
Securities
Number of issuers	63	82
Amortized Cost	59,979,000	82,884,000
Fair Value	61,058,000	83,804,000
Average Exposure Per Issuer (Fair Value)	969,000	1,022,000
General obligation bonds | Wisconsin
Securities
Number of issuers	39	41
Amortized Cost	36,165,000	43,117,000
Fair Value	36,365,000	43,122,000
Average Exposure Per Issuer (Fair Value)	932,000	1,052,000
General obligation bonds | Michigan
Securities
Number of issuers	33	37
Amortized Cost	30,400,000	35,350,000
Fair Value	30,739,000	35,365,000
Average Exposure Per Issuer (Fair Value)	931,000	956,000
General obligation bonds | Pennsylvania
Securities
Number of issuers	10	11
Amortized Cost	12,756,000	14,132,000
Fair Value	12,761,000	14,133,000
Average Exposure Per Issuer (Fair Value)	1,276,000	1,285,000
General obligation bonds | Ohio
Securities
Number of issuers	8	12
Amortized Cost	9,954,000	11,709,000
Fair Value	9,922,000	11,426,000
Average Exposure Per Issuer (Fair Value)	1,240,000	952,000
General obligation bonds | Texas
Securities
Number of issuers	7	7
Amortized Cost	7,364,000	7,510,000
Fair Value	7,313,000	7,270,000
Average Exposure Per Issuer (Fair Value)	1,045,000	1,039,000
General obligation bonds | Iowa
Securities
Number of issuers	3	3
Amortized Cost	6,116,000	6,126,000
Fair Value	6,142,000	6,060,000
Average Exposure Per Issuer (Fair Value)	2,047,000	2,020,000
General obligation bonds | Other
Securities
Number of issuers	24	26
Amortized Cost	18,862,000	21,865,000
Fair Value	19,370,000	22,290,000
Average Exposure Per Issuer (Fair Value)	807,000	857,000
Revenue bonds
Securities
Number of issuers	33	48
Amortized Cost	38,013,000	50,218,000
Fair Value	37,862,000	49,513,000
Average Exposure Per Issuer (Fair Value)	1,147,000	1,032,000
Amount of largest exposure to a single issuer	3,000,000
Percentage of the entity's stockholders equity in excess of aggregate book or market value	10.00%	10.00%
Minimum number of nationally recognized statistical rating organizations	1
Revenue bonds | Illinois
Securities
Number of issuers	4	4
Amortized Cost	6,772,000	7,356,000
Fair Value	6,708,000	7,121,000
Average Exposure Per Issuer (Fair Value)	1,677,000	1,780,000
Revenue bonds | Indiana
Securities
Number of issuers	8	14
Amortized Cost	12,520,000	14,740,000
Fair Value	12,469,000	14,481,000
Average Exposure Per Issuer (Fair Value)	1,559,000	1,034,000
Revenue bonds | Other
Securities
Number of issuers	21	30
Amortized Cost	18,721,000	28,122,000
Fair Value	18,685,000	27,911,000
Average Exposure Per Issuer (Fair Value)	890,000	930,000
Obligations of states and political subdivisions
Securities
Available for sale, fair value	220,161,000	272,152,000
Held to maturity, fair value	1,371,000	831,000
Number of issuers	220	267
Total Risk Based Capital for rated securities (as a percent)	100.00%
Total Risk Based Capital for unrated securities (as a percent)	15.00%
Obligations of states and political subdivisions | General obligation bonds
Securities
Available for sale, fair value	220,200,000	272,200,000
Held to maturity, fair value	1,400,000	800,000
Fair Value	183,700,000	223,500,000
Number of states in which investment is held	23	25
Number of states in which investment is held in excess of aggregate fair value	7	7
Aggregate fair value	5,000,000	5,000,000
Obligations of states and political subdivisions | Revenue bonds
Securities
Fair Value	37,900,000	49,500,000
Number of states in which investment is held	15	21
Number of states in which investment is held in excess of aggregate fair value	2	2
Aggregate fair value	$5,000,000	$5,000,000

Loans_Details

Loans (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	item
	mi
Loans
Total	$2,415,690,000	$2,295,300,000
Less held for sale	10,400,000	13,840,000
Total loans before allowance for loan losses	2,405,290,000	2,281,460,000
Less allowance for loan losses	47,453,000	47,567,000	48,012,000	58,506,000
Net loans	2,357,837,000	2,233,893,000
Net deferred loan origination costs	600,000
Minimum target period for lending via intermediate term loans	0 years
Maximum target period for lending via intermediate term loans	7 years
Geographical area from lending offices which attempt is made to lend short and intermediate term loans (in miles)	125
Direct and indirect maximum total borrowing relationship limit	20,000,000
Borrowing relationships, threshold above which board of directors will review annually	20,000,000
Number of primary areas for lending loan	5
Illinois
Loans
Total	1,909,668,000	1,814,155,000
Florida
Loans
Total	313,152,000	301,873,000
Total loans before allowance for loan losses	312,528,000	301,125,000
Less allowance for loan losses	8,511,000	13,118,000	15,433,000	19,469,000
Indiana
Loans
Total	192,870,000	179,272,000
Commercial
Loans
Total	601,760,000	580,612,000
Commercial | Illinois
Loans
Total	554,779,000	530,174,000
Commercial | Florida
Loans
Total	16,739,000	20,536,000
Total loans before allowance for loan losses	16,739,000	20,536,000
Less allowance for loan losses	1,172,000	1,926,000	1,437,000	1,939,000
Commercial | Indiana
Loans
Total	30,242,000	29,902,000
Commercial real estate
Loans
Total	1,104,151,000	1,092,273,000
Commercial real estate | Illinois
Loans
Total	811,034,000	800,568,000
Commercial real estate | Florida
Loans
Total	171,243,000	160,255,000
Total loans before allowance for loan losses	171,243,000	160,255,000
Less allowance for loan losses	4,205,000	5,733,000	6,062,000	8,413,000
Commercial real estate | Indiana
Loans
Total	121,874,000	131,450,000
Real estate construction
Loans
Total	107,054,000	78,855,000
Real estate construction | Illinois
Loans
Total	60,994,000	55,190,000
Real estate construction | Florida
Loans
Total	17,950,000	17,426,000
Total loans before allowance for loan losses	17,950,000	17,426,000
Less allowance for loan losses	205,000	1,168,000	2,315,000	2,936,000
Real estate construction | Indiana
Loans
Total	28,110,000	6,239,000
Retail real estate
Loans
Total	592,473,000	534,493,000
Minimum term of long-term loans entity sells to secondary market purchasers	15 years
Maximum term of loans entity retains	15 years
Retail real estate | Illinois
Loans
Total	473,171,000	419,801,000
Retail real estate | Florida
Loans
Total	106,658,000	103,104,000
Total loans before allowance for loan losses	106,034,000	102,356,000
Less allowance for loan losses	2,917,000	4,287,000	5,614,000	6,160,000
Retail real estate | Indiana
Loans
Total	12,644,000	11,588,000
Retail other
Loans
Total	10,252,000	9,067,000
Retail other | Illinois
Loans
Total	9,690,000	8,422,000
Retail other | Florida
Loans
Total	562,000	552,000
Total loans before allowance for loan losses	562,000	552,000
Less allowance for loan losses	12,000	4,000	5,000	21,000
Retail other | Indiana
Loans
Total		$93,000

Loans_Details_2

Loans (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Grades 1, 3, 6 and 7
Loans
Loans receivable	$2,280,000,000	$2,120,000,000
Increase or decrease in loans receivable	160,900,000
Grades 8, 9, and 10
Loans
Loans receivable	124,000,000	161,900,000
Increase or decrease in loans receivable	-37,900,000
Grades 1,3,6
Loans
Loans receivable	2,133,254,000	1,928,794,000
Grades 1,3,6 | Illinois/Indiana
Loans
Loans receivable	1,896,770,000	1,710,039,000
Grades 1,3,6 | Florida
Loans
Loans receivable	236,484,000	218,755,000
Grade 7
Loans
Loans receivable	145,154,000	188,741,000
Grade 7 | Illinois/Indiana
Loans
Loans receivable	107,843,000	152,084,000
Grade 7 | Florida
Loans
Loans receivable	37,311,000	36,657,000
Grade 8
Loans
Loans receivable	66,605,000	77,253,000
Grade 8 | Illinois/Indiana
Loans
Loans receivable	50,309,000	52,625,000
Grade 8 | Florida
Loans
Loans receivable	16,296,000	24,628,000
Grade 9
Loans
Loans receivable	48,438,000	67,531,000
Grade 9 | Illinois/Indiana
Loans
Loans receivable	29,702,000	50,240,000
Grade 9 | Florida
Loans
Loans receivable	18,736,000	17,291,000
Grade 10
Loans
Loans receivable	9,000,000	17,164,000
Grade 10 | Illinois/Indiana
Loans
Loans receivable	5,299,000	13,370,000
Grade 10 | Florida
Loans
Loans receivable	3,701,000	3,794,000
Commercial
Loans
Limit above which loans are processed through an expedited underwriting process	1,000,000
Limit above which loans are annually reviewed	1,000,000
Commercial | Illinois/Indiana
Loans
Weighted Avg. Risk Grade	4.8	4.66
Commercial | Florida
Loans
Weighted Avg. Risk Grade	5.4	5.89
Commercial | Grades 1,3,6
Loans
Limit above which loans are processed through an expedited underwriting process	350,000
Commercial | Grades 1,3,6 | Minimum
Loans
Limit above which loans are processed through an expedited underwriting process	350,000
Commercial | Grades 1,3,6 | Maximum
Loans
Limit above which loans are processed through an expedited underwriting process	1,000,000
Commercial | Grades 1,3,6 | Illinois/Indiana
Loans
Loans receivable	542,796,000	487,587,000
Commercial | Grades 1,3,6 | Florida
Loans
Loans receivable	13,455,000	16,460,000
Commercial | Grade 7
Loans
Limit above which loans are processed through an expedited underwriting process	1,000,000
Limit above which loans are annually reviewed	1,000,000
Commercial | Grade 7 | Illinois/Indiana
Loans
Loans receivable	27,032,000	46,992,000
Commercial | Grade 7 | Florida
Loans
Loans receivable	105,000	174,000
Commercial | Grade 8
Loans
Limit above which loans are annually reviewed	1,000,000
Commercial | Grade 8 | Illinois/Indiana
Loans
Loans receivable	8,549,000	15,986,000
Commercial | Grade 8 | Florida
Loans
Loans receivable	78,000	3,218,000
Commercial | Grade 9 | Illinois/Indiana
Loans
Loans receivable	5,498,000	8,536,000
Commercial | Grade 9 | Florida
Loans
Loans receivable	1,459,000	684,000
Commercial | Grade 10 | Illinois/Indiana
Loans
Loans receivable	1,146,000	975,000
Commercial | Grade 10 | Florida
Loans
Loans receivable	1,642,000
Commercial real estate | Illinois/Indiana
Loans
Weighted Avg. Risk Grade	5.67	5.55
Commercial real estate | Florida
Loans
Weighted Avg. Risk Grade	6	6.02
Commercial real estate | Grades 1,3,6 | Illinois/Indiana
Loans
Loans receivable	819,708,000	799,117,000
Commercial real estate | Grades 1,3,6 | Florida
Loans
Loans receivable	123,807,000	116,741,000
Commercial real estate | Grade 7 | Illinois/Indiana
Loans
Loans receivable	64,975,000	79,371,000
Commercial real estate | Grade 7 | Florida
Loans
Loans receivable	25,520,000	16,470,000
Commercial real estate | Grade 8 | Illinois/Indiana
Loans
Loans receivable	25,719,000	19,327,000
Commercial real estate | Grade 8 | Florida
Loans
Loans receivable	6,002,000	11,250,000
Commercial real estate | Grade 9 | Illinois/Indiana
Loans
Loans receivable	19,821,000	29,606,000
Commercial real estate | Grade 9 | Florida
Loans
Loans receivable	15,404,000	12,721,000
Commercial real estate | Grade 10 | Illinois/Indiana
Loans
Loans receivable	2,685,000	4,597,000
Commercial real estate | Grade 10 | Florida
Loans
Loans receivable	510,000	3,073,000
Real estate construction | Illinois/Indiana
Loans
Weighted Avg. Risk Grade	5.91	7.11
Real estate construction | Florida
Loans
Weighted Avg. Risk Grade	6.21	6.64
Real estate construction | Grades 1,3,6 | Illinois/Indiana
Loans
Loans receivable	71,074,000	21,585,000
Real estate construction | Grades 1,3,6 | Florida
Loans
Loans receivable	16,475,000	7,886,000
Real estate construction | Grade 7 | Illinois/Indiana
Loans
Loans receivable	5,332,000	16,376,000
Real estate construction | Grade 7 | Florida
Loans
Loans receivable		7,961,000
Real estate construction | Grade 8 | Illinois/Indiana
Loans
Loans receivable	11,448,000	11,920,000
Real estate construction | Grade 8 | Florida
Loans
Loans receivable	615,000	743,000
Real estate construction | Grade 9 | Illinois/Indiana
Loans
Loans receivable	1,204,000	7,686,000
Real estate construction | Grade 9 | Florida
Loans
Loans receivable	842,000	836,000
Real estate construction | Grade 10 | Illinois/Indiana
Loans
Loans receivable	46,000	3,862,000
Real estate construction | Grade 10 | Florida
Loans
Loans receivable	18,000
Retail real estate | Illinois/Indiana
Loans
Weighted Avg. Risk Grade	3.46	3.53
Retail real estate | Florida
Loans
Weighted Avg. Risk Grade	4.09	3.85
Retail real estate | Grades 1,3,6 | Illinois/Indiana
Loans
Loans receivable	453,560,000	393,299,000
Retail real estate | Grades 1,3,6 | Florida
Loans
Loans receivable	82,185,000	77,116,000
Retail real estate | Grade 7 | Illinois/Indiana
Loans
Loans receivable	10,478,000	9,285,000
Retail real estate | Grade 7 | Florida
Loans
Loans receivable	11,686,000	12,052,000
Retail real estate | Grade 8 | Illinois/Indiana
Loans
Loans receivable	4,569,000	5,392,000
Retail real estate | Grade 8 | Florida
Loans
Loans receivable	9,601,000	9,417,000
Retail real estate | Grade 9 | Illinois/Indiana
Loans
Loans receivable	3,179,000	4,408,000
Retail real estate | Grade 9 | Florida
Loans
Loans receivable	1,031,000	3,050,000
Retail real estate | Grade 10 | Illinois/Indiana
Loans
Loans receivable	1,414,000	3,936,000
Retail real estate | Grade 10 | Florida
Loans
Loans receivable	1,531,000	721,000
Retail other | Illinois/Indiana
Loans
Weighted Avg. Risk Grade	3.21	2.64
Retail other | Florida
Loans
Weighted Avg. Risk Grade	2.94	1.72
Retail other | Grades 1,3,6 | Illinois/Indiana
Loans
Loans receivable	9,632,000	8,451,000
Retail other | Grades 1,3,6 | Florida
Loans
Loans receivable	562,000	552,000
Retail other | Grade 7 | Illinois/Indiana
Loans
Loans receivable	26,000	60,000
Retail other | Grade 8 | Illinois/Indiana
Loans
Loans receivable	24,000
Retail other | Grade 9 | Illinois/Indiana
Loans
Loans receivable		4,000
Retail other | Grade 10 | Illinois/Indiana
Loans
Loans receivable	$8,000

Loans_Details_3

Loans (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loans past due, still accruing
30-59 Days	$1,586,000	$1,976,000
60-89 Days	233,000	4,138,000
90+Days	10,000	195,000
Non-accrual Loans	9,000,000	17,164,000
Minimum period past due as criterion for assessing impairment of loans	60 days
Minimum amount criterion for assessing impairment of loans	250,000
Loans assessed for impairment if loans are above a particular limit and are of eighth grade	500,000
Amount of problem loans sold from HS portfolio, net of charge-offs	3,800,000	7,600,000
Gross interest income that would have been recorded if impaired loans had been current	800,000	1,300,000	3,400,000
Restructured loan included in the non-performing loan	90 days
Restructured loans
Total loans	12,992,000	17,810,000
Illinois/Indiana
Loans past due, still accruing
30-59 Days	1,586,000	1,976,000
60-89 Days	233,000	4,138,000
90+Days	10,000	195,000
Non-accrual Loans	5,299,000	13,370,000
Florida
Loans past due, still accruing
Non-accrual Loans	3,701,000	3,794,000
In compliance with modified terms
Restructured loans
Total loans	11,866,000	11,511,000
30-89 days past due
Restructured loans
Total loans		380,000
Included in non-performing loans
Restructured loans
Total loans	1,126,000	5,919,000
Commercial | Illinois/Indiana
Loans past due, still accruing
30-59 Days	15,000	906,000
60-89 Days	105,000	279,000
90+Days		92,000
Non-accrual Loans	1,146,000	975,000
Commercial | Florida
Loans past due, still accruing
Non-accrual Loans	1,642,000
Commercial real estate | Illinois/Indiana
Loans past due, still accruing
30-59 Days	1,068,000	567,000
60-89 Days		3,736,000
90+Days	10,000
Non-accrual Loans	2,685,000	4,597,000
Commercial real estate | Florida
Loans past due, still accruing
Non-accrual Loans	510,000	3,073,000
Real estate construction | Illinois/Indiana
Loans past due, still accruing
Non-accrual Loans	46,000	3,862,000
Real estate construction | Florida
Loans past due, still accruing
Non-accrual Loans	18,000
Retail real estate | Illinois/Indiana
Loans past due, still accruing
30-59 Days	488,000	483,000
60-89 Days	128,000	123,000
90+Days		103,000
Non-accrual Loans	1,414,000	3,936,000
Retail real estate | Florida
Loans past due, still accruing
Non-accrual Loans	1,531,000	721,000
Retail other | Illinois/Indiana
Loans past due, still accruing
30-59 Days	15,000	20,000
Non-accrual Loans	$8,000

Loans_Details_4

Loans (Details 4) (USD $)	12 Months Ended		3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2014
			item	item
Loans
Unpaid Contractual Principal Balance	$30,124,000	$40,077,000	40,077,000	$30,124,000
Recorded Investment with No Allowance	21,289,000	24,282,000	24,282,000	21,289,000
Recorded Investment with Allowance	5,297,000	9,778,000	9,778,000	5,297,000
Total Recorded Investment	26,586,000	34,060,000	34,060,000	26,586,000
Related Allowance	3,168,000	4,287,000	4,287,000	3,168,000
Average Recorded Investment	28,668,000	44,724,000
Minimum days past due for TDR loans to be classified as non-performing	90 days
Illinois/Indiana
Loans
Unpaid Contractual Principal Balance	9,799,000	22,206,000	22,206,000	9,799,000
Recorded Investment with No Allowance	4,927,000	10,914,000	10,914,000	4,927,000
Recorded Investment with Allowance	3,666,000	7,922,000	7,922,000	3,666,000
Total Recorded Investment	8,593,000	18,836,000	18,836,000	8,593,000
Related Allowance	2,641,000	3,534,000	3,534,000	2,641,000
Average Recorded Investment	13,284,000	25,689,000
Florida
Loans
Unpaid Contractual Principal Balance	20,325,000	17,871,000	17,871,000	20,325,000
Recorded Investment with No Allowance	16,362,000	13,368,000	13,368,000	16,362,000
Recorded Investment with Allowance	1,631,000	1,856,000	1,856,000	1,631,000
Total Recorded Investment	17,993,000	15,224,000	15,224,000	17,993,000
Related Allowance	527,000	753,000	753,000	527,000
Average Recorded Investment	15,384,000	19,035,000
Included in non-performing loans
Loans
Number of contracts			0
Commercial | Illinois/Indiana
Loans
Unpaid Contractual Principal Balance	2,944,000	2,825,000	2,825,000	2,944,000
Recorded Investment with No Allowance	1,376,000	1,684,000	1,684,000	1,376,000
Recorded Investment with Allowance	741,000	602,000	602,000	741,000
Total Recorded Investment	2,117,000	2,286,000	2,286,000	2,117,000
Related Allowance	595,000	485,000	485,000	595,000
Average Recorded Investment	2,479,000	4,169,000
Commercial | Florida
Loans
Unpaid Contractual Principal Balance	2,742,000			2,742,000
Recorded Investment with No Allowance	1,642,000			1,642,000
Total Recorded Investment	1,642,000			1,642,000
Average Recorded Investment	330,000
Commercial | In compliance with modified terms | Illinois/Indiana
Loans
Number of modifications for short-term principal payment relief		1	1
Recorded investment for short-term principal payment relief		100,000	100,000
Commercial real estate | Illinois/Indiana
Loans
Unpaid Contractual Principal Balance	4,007,000	8,866,000	8,866,000	4,007,000
Recorded Investment with No Allowance	1,140,000	3,671,000	3,671,000	1,140,000
Recorded Investment with Allowance	2,854,000	3,740,000	3,740,000	2,854,000
Total Recorded Investment	3,994,000	7,411,000	7,411,000	3,994,000
Related Allowance	1,975,000	1,977,000	1,977,000	1,975,000
Average Recorded Investment	5,473,000	10,335,000
Commercial real estate | Florida
Loans
Unpaid Contractual Principal Balance	5,775,000	7,108,000	7,108,000	5,775,000
Recorded Investment with No Allowance	4,414,000	3,946,000	3,946,000	4,414,000
Recorded Investment with Allowance	1,274,000	1,319,000	1,319,000	1,274,000
Total Recorded Investment	5,688,000	5,265,000	5,265,000	5,688,000
Related Allowance	370,000	416,000	416,000	370,000
Average Recorded Investment	5,032,000	6,662,000
Commercial real estate | In compliance with modified terms | Illinois/Indiana
Loans
Number of modifications for short-term principal payment relief		1
Recorded investment for short-term principal payment relief		200,000	200,000
Commercial real estate | In compliance with modified terms | Florida
Loans
Number of modifications for short-term principal payment relief	1			1
Recorded investment for short-term principal payment relief	2,000,000			2,000,000
Number of modifications for short-term interest-rate relief		1
Recorded investment for short-term interest-rate relief		100,000
Commercial real estate | Included in non-performing loans | Illinois/Indiana
Loans
Number of contracts	1	1
Recorded Investment	300,000	1,700,000
Real estate construction | Illinois/Indiana
Loans
Unpaid Contractual Principal Balance	46,000	4,932,000	4,932,000	46,000
Recorded Investment with No Allowance		2,292,000	2,292,000
Recorded Investment with Allowance	46,000	1,570,000	1,570,000	46,000
Total Recorded Investment	46,000	3,862,000	3,862,000	46,000
Related Allowance	46,000	468,000	468,000	46,000
Average Recorded Investment	2,269,000	5,889,000
Real estate construction | Florida
Loans
Unpaid Contractual Principal Balance	620,000	417,000	417,000	620,000
Recorded Investment with No Allowance	551,000	417,000	417,000	551,000
Total Recorded Investment	551,000	417,000	417,000	551,000
Average Recorded Investment	485,000	1,294,000
Real estate construction | Included in non-performing loans | Illinois/Indiana
Loans
Number of contracts		1
Recorded Investment		200,000
Retail real estate | Illinois/Indiana
Loans
Unpaid Contractual Principal Balance	2,794,000	5,583,000	5,583,000	2,794,000
Recorded Investment with No Allowance	2,403,000	3,267,000	3,267,000	2,403,000
Recorded Investment with Allowance	25,000	2,010,000	2,010,000	25,000
Total Recorded Investment	2,428,000	5,277,000	5,277,000	2,428,000
Related Allowance	25,000	604,000	604,000	25,000
Average Recorded Investment	3,061,000	5,296,000
Retail real estate | Florida
Loans
Unpaid Contractual Principal Balance	11,181,000	10,346,000	10,346,000	11,181,000
Recorded Investment with No Allowance	9,755,000	9,005,000	9,005,000	9,755,000
Recorded Investment with Allowance	350,000	537,000	537,000	350,000
Total Recorded Investment	10,105,000	9,542,000	9,542,000	10,105,000
Related Allowance	150,000	337,000	337,000	150,000
Average Recorded Investment	9,532,000	11,079,000
Retail real estate | Included in non-performing loans | Illinois/Indiana
Loans
Number of contracts		1
Recorded Investment		500,000
Retail other | Illinois/Indiana
Loans
Unpaid Contractual Principal Balance	8,000			8,000
Recorded Investment with No Allowance	8,000			8,000
Total Recorded Investment	8,000			8,000
Average Recorded Investment	2,000
Retail other | Florida
Loans
Unpaid Contractual Principal Balance	7,000			7,000
Recorded Investment with Allowance	7,000			7,000
Total Recorded Investment	7,000			7,000
Related Allowance	7,000			7,000
Average Recorded Investment	$5,000

Loans_Details_5

Loans (Details 5) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Loans
The number of components in the general portion of the Company's allowance	2
Number of quarters whose historical average is used to calculate the historical loss ratio	20
Increase in allowances	1.3
Grade 9
Loans
Period of charge-off percentage based on which additional allocation is determined	1 year
Minimum additional reserve (as a percent)	3.00%	3.00%
Grade 8
Loans
Number of quarters in more current measure of historical losses in adversely graded loans	12
Number of quarters in less current measure of historical losses in adversely graded loans	20
Minimum additional amount for loans (as a percent)	1.00%	1.00%

Loans_Details_6

Loans (Details 6) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in allowance for loan losses
Beginning balance	$47,567	$48,012	$58,506
Provision for loan loss	2,000	7,500	16,500
Charged-off	-7,371	-10,669	-30,063
Recoveries	5,257	2,724	3,069
Ending Balance	47,453	47,567	48,012
Amount allocated to:
Ending Balance	47,453	47,567	48,012
Loans:
Ending Balance	2,405,290	2,281,460
Illinois/Indiana
Changes in allowance for loan losses
Beginning balance	34,449	32,579	39,037
Provision for loan loss	6,532	6,350	15,891
Charged-off	-5,519	-6,235	-23,975
Recoveries	3,480	1,755	1,626
Ending Balance	38,942	34,449	32,579
Amount allocated to:
Loans individually evaluated for impairment	2,641	3,534
Loans collectively evaluated for impairment	36,301	30,915
Ending Balance	38,942	34,449	32,579
Loans:
Loans individually evaluated for impairment	8,593	18,836
Loans collectively evaluated for impairment	2,084,169	1,961,499
Ending Balance	2,092,762	1,980,335
Florida
Changes in allowance for loan losses
Beginning balance	13,118	15,433	19,469
Provision for loan loss	-4,532	1,150	609
Charged-off	-1,852	-4,434	-6,088
Recoveries	1,777	969	1,443
Ending Balance	8,511	13,118	15,433
Amount allocated to:
Loans individually evaluated for impairment	527	753
Loans collectively evaluated for impairment	7,984	12,365
Ending Balance	8,511	13,118	15,433
Loans:
Loans individually evaluated for impairment	17,993	15,224
Loans collectively evaluated for impairment	294,535	285,901
Ending Balance	312,528	301,125
Commercial | Illinois/Indiana
Changes in allowance for loan losses
Beginning balance	8,452	6,597	9,143
Provision for loan loss	1,048	2,681	1,428
Charged-off	-864	-964	-4,176
Recoveries	233	138	202
Ending Balance	8,869	8,452	6,597
Amount allocated to:
Loans individually evaluated for impairment	595	485
Loans collectively evaluated for impairment	8,274	7,967
Ending Balance	8,869	8,452	6,597
Loans:
Loans individually evaluated for impairment	2,117	2,286
Loans collectively evaluated for impairment	582,904	557,790
Ending Balance	585,021	560,076
Commercial | Florida
Changes in allowance for loan losses
Beginning balance	1,926	1,437	1,939
Provision for loan loss	195	414	-811
Charged-off	-1,126		-246
Recoveries	177	75	555
Ending Balance	1,172	1,926	1,437
Amount allocated to:
Loans collectively evaluated for impairment	1,172	1,926
Ending Balance	1,172	1,926	1,437
Loans:
Loans individually evaluated for impairment	1,642
Loans collectively evaluated for impairment	15,097	20,536
Ending Balance	16,739	20,536
Commercial real estate | Illinois/Indiana
Changes in allowance for loan losses
Beginning balance	16,379	15,023	18,605
Provision for loan loss	-880	2,143	10,058
Charged-off	-1,173	-1,361	-14,016
Recoveries	2,108	574	376
Ending Balance	16,434	16,379	15,023
Amount allocated to:
Loans individually evaluated for impairment	1,975	1,977
Loans collectively evaluated for impairment	14,459	14,402
Ending Balance	16,434	16,379	15,023
Loans:
Loans individually evaluated for impairment	3,994	7,411
Loans collectively evaluated for impairment	928,914	924,607
Ending Balance	932,908	932,018
Commercial real estate | Florida
Changes in allowance for loan losses
Beginning balance	5,733	6,062	8,413
Provision for loan loss	-1,799	2,225	-619
Charged-off		-2,543	-1,858
Recoveries	271	-11	126
Ending Balance	4,205	5,733	6,062
Amount allocated to:
Loans individually evaluated for impairment	370	416
Loans collectively evaluated for impairment	3,835	5,317
Ending Balance	4,205	5,733	6,062
Loans:
Loans individually evaluated for impairment	5,688	5,265
Loans collectively evaluated for impairment	165,555	154,990
Ending Balance	171,243	160,255
Real estate construction | Illinois/Indiana
Changes in allowance for loan losses
Beginning balance	2,540	2,527	4,352
Provision for loan loss	90	847	-270
Charged-off	-657	-1,212	-1,883
Recoveries	617	378	328
Ending Balance	2,590	2,540	2,527
Amount allocated to:
Loans individually evaluated for impairment	46	468
Loans collectively evaluated for impairment	2,544	2,072
Ending Balance	2,590	2,540	2,527
Loans:
Loans individually evaluated for impairment	46	3,862
Loans collectively evaluated for impairment	89,058	57,567
Ending Balance	89,104	61,429
Real estate construction | Florida
Changes in allowance for loan losses
Beginning balance	1,168	2,315	2,936
Provision for loan loss	-1,889	-1,419	-555
Charged-off	-69	-56	-336
Recoveries	995	328	270
Ending Balance	205	1,168	2,315
Amount allocated to:
Loans collectively evaluated for impairment	205	1,168
Ending Balance	205	1,168	2,315
Loans:
Loans individually evaluated for impairment	551	417
Loans collectively evaluated for impairment	17,399	17,009
Ending Balance	17,950	17,426
Retail real estate | Illinois/Indiana
Changes in allowance for loan losses
Beginning balance	6,862	8,110	6,473
Provision for loan loss	5,942	616	4,397
Charged-off	-2,396	-2,187	-3,264
Recoveries	337	323	504
Ending Balance	10,745	6,862	8,110
Amount allocated to:
Loans individually evaluated for impairment	25	604
Loans collectively evaluated for impairment	10,720	6,258
Ending Balance	10,745	6,862	8,110
Loans:
Loans individually evaluated for impairment	2,428	5,277
Loans collectively evaluated for impairment	473,611	413,020
Ending Balance	476,039	418,297
Retail real estate | Florida
Changes in allowance for loan losses
Beginning balance	4,287	5,614	6,160
Provision for loan loss	-1,021	-51	2,626
Charged-off	-656	-1,828	-3,646
Recoveries	307	552	474
Ending Balance	2,917	4,287	5,614
Amount allocated to:
Loans individually evaluated for impairment	150	337
Loans collectively evaluated for impairment	2,767	3,950
Ending Balance	2,917	4,287	5,614
Loans:
Loans individually evaluated for impairment	10,105	9,542
Loans collectively evaluated for impairment	95,929	92,814
Ending Balance	106,034	102,356
Retail other | Illinois/Indiana
Changes in allowance for loan losses
Beginning balance	216	322	464
Provision for loan loss	332	63	278
Charged-off	-429	-511	-636
Recoveries	185	342	216
Ending Balance	304	216	322
Amount allocated to:
Loans collectively evaluated for impairment	304	216
Ending Balance	304	216	322
Loans:
Loans individually evaluated for impairment	8
Loans collectively evaluated for impairment	9,682	8,515
Ending Balance	9,690	8,515
Retail other | Florida
Changes in allowance for loan losses
Beginning balance	4	5	21
Provision for loan loss	-18	-19	-32
Charged-off	-1	-7	-2
Recoveries	27	25	18
Ending Balance	12	4	5
Amount allocated to:
Loans individually evaluated for impairment	7
Loans collectively evaluated for impairment	5	4
Ending Balance	12	4	5
Loans:
Loans individually evaluated for impairment	7
Loans collectively evaluated for impairment	555	552
Ending Balance	$562	$552

Loan_Servicing_Details

Loan Servicing (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loan Servicing
Unpaid principal balances of loans serviced by the entity for the benefit of others	$1,390,000,000	$1,440,000,000
Capitalized servicing rights included in other assets	3,900,000	5,100,000
Fair values of servicing rights	5,200,000	6,400,000
Mortgage servicing rights capitalized and amortized
Mortgage servicing rights capitalized	983,000	2,490,000	2,794,000
Mortgage servicing rights amortized	$2,228,000	$2,650,000	$2,972,000

Premises_and_Equipment_Details

Premises and Equipment (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Premises and Equipment
Premises and equipment, gross	$116,371,000	$117,313,000
Less accumulated depreciation	52,397,000	51,486,000
Total premises and equipment	63,974,000	65,827,000
Depreciation expense	5,600,000	5,500,000	5,400,000
Land and improvements
Premises and Equipment
Premises and equipment, gross	21,559,000	21,532,000
Buildings and improvements
Premises and Equipment
Premises and equipment, gross	62,794,000	62,159,000
Furniture and equipment
Premises and Equipment
Premises and equipment, gross	$32,018,000	$33,622,000

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Goodwill and other intangibles assets
Goodwill impairment	$0	$0
Changes in the carrying amount of goodwill	0	0
Total Goodwill	20,686	20,686
FirsTech
Goodwill and other intangibles assets
Total Goodwill	8,992	8,992
Busey Wealth Management
Goodwill and other intangibles assets
Total Goodwill	$11,694	$11,694

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Amortized intangible assets:
Balance at the beginning of period	$9,571
Amortization	2,884	3,132	3,315
Balance at the end of period	6,687	9,571
Core deposit intangible assets
Amortized intangible assets:
Balance at the beginning of period	6,124
Amortization	1,870
Balance at the end of period	4,254
Core deposit intangible assets | Maximum
Goodwill and other intangibles assets
Intangible asset estimated period	10 years
Customer relationship intangible assets
Amortized intangible assets:
Balance at the beginning of period	3,447
Amortization	1,014
Balance at the end of period	$2,433

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Goodwill and other intangibles assets
Net carrying amount	$6,687	$9,571
Estimated amortization expense:
Net carrying amount	6,687	9,571
Core deposit intangible assets
Goodwill and other intangibles assets
Gross carrying amount	19,962
Accumulated amortization	15,708
Net carrying amount	4,254	6,124
Estimated amortization expense:
2015	1,719
2016	1,644
2017	891
Net carrying amount	4,254	6,124
Customer relationship intangible assets
Goodwill and other intangibles assets
Gross carrying amount	11,320
Accumulated amortization	8,887
Net carrying amount	2,433	3,447
Estimated amortization expense:
2015	972
2016	929
2017	532
Net carrying amount	$2,433	$3,447

Deposits_Details

Deposits (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Deposits
Demand deposits, non-interest-bearing	$666,607,000	$547,531,000
Interest-bearing transaction deposits	67,774,000	61,384,000
Savings deposits	210,673,000	206,587,000
Money market deposits	1,459,723,000	1,471,265,000
Time deposits	496,071,000	582,371,000
Total deposits	2,900,848,000	2,869,138,000
Time deposits minimum denomination of $100,000 or more	138,400,000	163,700,000
Time deposits minimum denomination of $250,000 or more	24,400,000	28,800,000
Brokered and National included in the balance of time deposits	500,000
Deposits
2015	309,598,000
2016	95,118,000
2017	61,161,000
2018	18,934,000
2019	11,250,000
Thereafter	10,000
Total	$496,071,000	$582,371,000

Securities_Sold_Under_Agreemen

Securities Sold Under Agreements to Repurchase (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Federal Funds Purchased and Securities Sold Under Agreements to Repurchase
Maximum maturity period of securities sold under agreements to repurchase	1 year
Balance	$198,893	$172,348
Weighted average interest rate at end of period (as a percent)	0.14%	0.13%
Maximum outstanding at any month end	198,893	172,348
Average daily balance	$148,452	$137,777
Weighted average interest rate during period (as a percent)	0.12%	0.14%

Shortterm_Borrowings_Details

Short-term Borrowings (Details) (Line of Credit, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Line of Credit
Short-term borrowings
Outstanding amounts	$0	$0

Longterm_Debt_Details

Long-term Debt (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Long-term debt
Long-term debt	$50,000
Notes payable, Federal Home Loan Bank of Chicago
Long-term debt
Long-term debt	$50,000
Interest rate, minimum (as a percent)	0.07%
Interest rate, maximum (as a percent)	0.13%
Weighted average rate (as a percent)	0.09%
Notes payable, Federal Home Loan Bank of Chicago | Maximum
Long-term debt
Notes payable maturity date	10 years

Junior_Subordinated_Debt_Owed_2

Junior Subordinated Debt Owed to Unconsolidated Trusts (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
Junior subordinated debt owed to unconsolidated trusts
Maximum assets of bank holding companies for inclusion of proceeds of trust preferred securities from Tier 1 capital unless such securities were issued prior to May 19, 2010	$15,000,000,000
Trust Preferred Securities
Junior subordinated debt owed to unconsolidated trusts
Percentage limit on inclusion of qualifying trust preferred securities in Tier I Capital	25.00%
Transition period for inclusion of qualifying trust preferred securities in Tier I Capital	5 years
Trust preferred securities qualified as Tier I capital (as a percent)	100.00%
Maximum assets of bank holding companies for inclusion of proceeds of trust preferred securities from Tier 1 capital unless such securities were issued prior to May 19, 2010	15,000,000,000
First Busey Statutory Trust II | Trust Preferred Securities
Junior subordinated debt owed to unconsolidated trusts
Face value	15,000,000
Base rate	3-mo LIBOR
Annual distribution rate margin (as a percent)	2.65%
First Busey Statutory Trust III | Trust Preferred Securities
Junior subordinated debt owed to unconsolidated trusts
Face value	10,000,000
Base rate	3-mo LIBOR
Annual distribution rate margin (as a percent)	1.75%
First Busey Statutory Trust IV | Trust Preferred Securities
Junior subordinated debt owed to unconsolidated trusts
Face value	30,000,000
Base rate	3-mo LIBOR
Annual distribution rate margin (as a percent)	1.55%
Term of trust preferred securities	5 years
Fixed coupon rate (as a percent)	6.94%
Junior Subordinated Notes | Trust Preferred Securities
Junior subordinated debt owed to unconsolidated trusts
Maximum period to defer payment of interest on the notes and, therefore, distributions on the trust preferred securities	5 years
Junior Subordinated Notes | First Busey Statutory Trust II
Junior subordinated debt owed to unconsolidated trusts
Principal balance	15,000,000
Base rate	3-mo LIBOR
Interest rate margin (as a percent)	2.65%
Junior Subordinated Notes | First Busey Statutory Trust III
Junior subordinated debt owed to unconsolidated trusts
Principal balance	10,000,000
Base rate	3-mo LIBOR
Interest rate margin (as a percent)	1.75%
Junior Subordinated Notes | First Busey Statutory Trust IV
Junior subordinated debt owed to unconsolidated trusts
Principal balance	$30,000,000
Base rate	3-mo LIBOR
Interest rate margin (as a percent)	1.55%
Term of debt	5 years
Fixed coupon rate (as a percent)	6.94%

Capital_Details

Capital (Details) (USD $)	0 Months Ended	1 Months Ended	12 Months Ended
	Aug. 25, 2011	Sep. 30, 2011	Dec. 31, 2013	Dec. 31, 2014
Capital
Preferred stock, liquidation value (in dollars per share)			1,000	$1,000
Number of shares of common stock that can be purchased by exercise of warrants	1,147,666
Percentage reduction in the number of shares of common stock that can be purchased by exercise of warrants	50.00%
Number of shares of common stock that can be purchased by exercise of warrants, after reduction	573,833
Warrants outstanding (in shares)			573,833
Preferred stock, shares outstanding			72,664	72,664
Series C Preferred stock
Capital
Shares issued	72,664
Preferred stock, liquidation value (in dollars per share)	1,000
Aggregate proceeds from issuance of shares	72,664,000
Series C Preferred stock | Initial dividend period
Capital
Dividend rate (as a percent)		5.00%
Series C Preferred stock | Period from the 2nd through the 10th calendar quarters
Capital
Dividend rate (as a percent)			5.00%
Series C Preferred stock | Period from the 11th calendar quarter through 4.5 years after issuance | Minimum
Capital
Dividend rate (as a percent)			1.00%
Series C Preferred stock | Period from the 11th calendar quarter through 4.5 years after issuance | Maximum
Capital
Dividend rate (as a percent)			7.00%
Series C Preferred stock | Period after 4.5 years from issuance
Capital
Dividend rate (as a percent)			9.00%
Series T Preferred stock
Capital
Shares redeemed	100,000
Redemption price	100,100,000

Capital_Details_2

Capital (Details 2) (USD $)	1 Months Ended	0 Months Ended		72 Months Ended
	Jul. 31, 2013	Oct. 22, 2014	Jan. 22, 2013	Dec. 31, 2014	Dec. 31, 2013
Total Capital (to Risk Weighted Assets), Amount
Actual				$488,908,000	$449,407,000
Minimum Capital Requirement				209,554,000	197,422,000
Minimum To Be Well Capitalized				261,942,000	246,777,000
Total Capital (to Risk Weighted Assets), Ratio
Actual (as a percent)				18.66%	18.21%
Minimum Capital Requirement (as a percent)				8.00%	8.00%
Minimum To Be Well Capitalized (as a percent)				10.00%	10.00%
Tier 1 Capital (to Risk Weighted Assets), Amount
Actual				455,354,000	417,564,000
Minimum Capital Requirement				104,777,000	98,711,000
Minimum To Be Well Capitalized				157,166,000	148,067,000
Tier 1 Capital (to Risk Weighted Assets), Ratio
Actual (as a percent)				17.38%	16.92%
Minimum Capital Requirement (as a percent)				4.00%	4.00%
Minimum To Be Well Capitalized (as a percent)				6.00%	6.00%
Tier 1 Capital (to Average Assets), Amount
Actual				455,354,000	417,564,000
Minimum Capital Requirement				142,401,000	138,896,000
Tier 1 Capital (to Average Assets), Ratio
Actual (as a percent)				12.79%	12.02%
Minimum Capital Requirement (as a percent)				4.00%	4.00%
Maximum assets of bank holding companies for inclusion of proceeds of trust preferred securities from Tier 1 capital unless such securities were issued prior to May 19, 2010				15,000,000,000
Dodd-Frank Act ("Basel III Rules")
Total Capital (to Risk Weighted Assets), Ratio
Minimum To Be Well Capitalized (as a percent)	10.00%
Tier 1 Capital (to Risk Weighted Assets), Ratio
Minimum To Be Well Capitalized (as a percent)	8.00%
Tier 1 Capital (to Average Assets), Ratio
Common equity Tier 1 Risk Based Capital to be well capitalized percentage	6.50%
Tier 1 Leverage Capital to be well capitalized percentage	5.00%
Maximum consolidated assets of bank holding companies	1,000,000,000
Maximum consolidated assets of bank holding companies to retain the existing treatment for accumulated other comprehensive income which currently does not affect regulatory capital				15,000,000,000
Busey Bank
Regulatory Capital
Dividends paid				0
Distribution received through chartered amendment		60,000,000	50,000,000
Total Capital (to Risk Weighted Assets), Amount
Actual				388,479,000	396,248,000
Minimum Capital Requirement				207,991,000	196,002,000
Minimum To Be Well Capitalized				259,988,000	245,002,000
Total Capital (to Risk Weighted Assets), Ratio
Actual (as a percent)				14.94%	16.17%
Minimum Capital Requirement (as a percent)				8.00%	8.00%
Minimum To Be Well Capitalized (as a percent)				10.00%	10.00%
Tier 1 Capital (to Risk Weighted Assets), Amount
Actual				355,166,000	364,625,000
Minimum Capital Requirement				103,996,000	98,001,000
Minimum To Be Well Capitalized				155,993,000	147,001,000
Tier 1 Capital (to Risk Weighted Assets), Ratio
Actual (as a percent)				13.66%	14.88%
Minimum Capital Requirement (as a percent)				4.00%	4.00%
Minimum To Be Well Capitalized (as a percent)				6.00%	6.00%
Tier 1 Capital (to Average Assets), Amount
Actual				355,166,000	364,625,000
Minimum Capital Requirement				140,677,000	136,818,000
Minimum To Be Well Capitalized				$175,846,000	$171,023,000
Tier 1 Capital (to Average Assets), Ratio
Actual (as a percent)				10.10%	10.66%
Minimum Capital Requirement (as a percent)				4.00%	4.00%
Minimum To Be Well Capitalized (as a percent)				5.00%	5.00%

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components of income taxes
Current									$4,830,000	$4,020,000	$1,926,000
Deferred									12,704,000	10,091,000	8,571,000
Total income tax expense	4,763,000	4,708,000	4,025,000	4,038,000	3,528,000	3,572,000	3,787,000	3,224,000	17,534,000	14,111,000	10,497,000
Reconciliation of federal and state income taxes at statutory rates to the income taxes included in the statements of operations
Income tax at statutory rate (as a percent)									35.00%	35.00%	35.00%
Tax-exempt interest, net (as a percent)									-2.60%	-3.50%	-4.50%
State income taxes, net (as a percent)									5.70%	4.50%	3.50%
Income on bank owned life insurance (as a percent)									-1.00%	-0.90%	-1.80%
Other, net (as a percent)									-2.20%	-2.20%	-0.30%
Total (as a percent)									34.90%	32.90%	31.90%
Deferred tax assets:
Allowance for loan losses	18,904,000				19,416,000				18,904,000	19,416,000
Stock-based compensation	1,472,000				1,319,000				1,472,000	1,319,000
Loan adjustments	94,000				108,000				94,000	108,000
Deferred compensation	2,057,000				2,015,000				2,057,000	2,015,000
Accrued vacation	527,000				545,000				527,000	545,000
Employee costs	656,000				1,264,000				656,000	1,264,000
Other	2,498,000				1,780,000				2,498,000	1,780,000
Total	26,208,000				26,447,000				26,208,000	26,447,000
Investment securities:
Unrealized gains on securities available for sale	-3,884,000				-3,119,000				-3,884,000	-3,119,000
Other	-1,997,000				-2,450,000				-1,997,000	-2,450,000
Basis in premises and equipment	-2,012,000				-2,590,000				-2,012,000	-2,590,000
Mortgage servicing assets	-1,549,000				-2,097,000				-1,549,000	-2,097,000
Basis in core deposit and customer intangible assets	-2,669,000				-3,908,000				-2,669,000	-3,908,000
Deferred loan origination costs	-257,000				-20,000				-257,000	-20,000
Deferred tax liabilities	-12,368,000				-14,184,000				-12,368,000	-14,184,000
Net operating loss carryforward, net of valuation allowance	8,333,000				23,379,000				8,333,000	23,379,000
Net deferred tax assets	22,173,000				35,642,000				22,173,000	35,642,000
Operating loss carryforwards
Valuation allowance required for other deferred tax assets	0								0
Indiana and Florida
Operating loss carryforwards
Net operating loss carryforwards	1,000,000				1,500,000				1,000,000	1,500,000
Valuation allowance	1,000,000								1,000,000
Federal
Operating loss carryforwards
Net operating loss carryforwards					33,000,000					33,000,000
Illinois
Operating loss carryforwards
Net operating loss carryforwards	$114,000,000				$171,000,000				$114,000,000	$171,000,000

Employee_Benefit_Plans_Details

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	479,755	543,471
Associated fair values of allocated shares acquired prior to December 31, 1992	$3,100,000	$3,200,000
Shares
Allocated shares	171,988	192,171
Fair Value
Allocated shares, Fair Value	1,100,000	1,100,000
Profit Sharing Plan
Vesting period	5 years
Expenses related to employee benefit plans
Employee benefits	2,636,000	2,975,000	3,024,000
Interest on employee stock ownership plan debt			5,000
Total employer contributions	2,636,000	2,975,000	3,029,000
Deferred compensation plans for deferral of performance bonuses
Deferred compensation expense	300,000	200,000	200,000
Deferred compensation liability	$5,100,000	$4,800,000	$4,500,000

Stock_Incentive_Plans_Details

Stock Incentive Plans (Details) (USD $)	0 Months Ended	12 Months Ended
	19-May-10	Dec. 31, 2014	Dec. 31, 2013	Feb. 03, 2015
Stock Incentive Plans
Maximum number of shares that may be delivered to participants		4,000,000
Period from effective date after which no awards may be granted	10 years
Stock Incentive Plans
Treasury Stock, Shares		1,426,323	1,482,777
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased		895,655
Maximum | Options and SARs
Stock Incentive Plans
Shares available for grant during any calendar year		400,000
Maximum | Stock awards
Stock Incentive Plans
Shares available for grant during any calendar year		200,000
Maximum | Cash incentive awards and cash-settled stock awards
Stock Incentive Plans
Amount of award payable with respect to any calendar year		1,000,000
Subsequent event
Stock Incentive Plans
Shares authorized for repurchase under stock repurchase plan				2,000,000

Stock_Incentive_Plans_Details_

Stock Incentive Plans (Details 2) (Stock option awards, USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock option awards
Shares
Outstanding at beginning of year (in shares)	696,379	857,468	1,017,922
Forfeited (in shares)	-186,249	-161,089	-160,454
Outstanding at end of period (in shares)	510,130	696,379	857,468
Exercisable at end of period (in shares)	510,130	696,379	857,468
Weighted-Average Exercise Price
Outstanding at beginning of year (in dollars per share)	$17.22	$17.01	$16.23
Forfeited (in dollars per share)	$19.67	$16.10	$12.07
Outstanding at end of period (in dollars per share)	$16.33	$17.22	$17.01
Exercisable at end of period (in dollars per share)	$16.33	$17.22	$17.01

Stock_Incentive_Plans_Details_1

Stock Incentive Plans (Details 3) (Stock option awards, USD $)	12 Months Ended
	Dec. 31, 2014
Options Outstanding
Number (in shares)	510,130
Weighted-Average Exercise Price (in dollars per share)	$16.33
Weighted-Average Remaining Contractual Life	1 year 8 months 16 days
Intrinsic Value (in dollars)	$106
Options Exercisable
Number (in shares)	510,130
Intrinsic Value (in dollars)	106
Unrecognized stock option expense	$0
$ 4.49-7.53
Range of Exercise Prices
Low end of the range (in dollars per share)	$4.49
High end of the range (in dollars per share)	$7.53
Options Outstanding
Number (in shares)	105,000
Weighted-Average Exercise Price (in dollars per share)	$6.01
Weighted-Average Remaining Contractual Life	5 years
Options Exercisable
Number (in shares)	105,000
$ 17.12-19.74
Range of Exercise Prices
Low end of the range (in dollars per share)	$17.12
High end of the range (in dollars per share)	$19.55
Options Outstanding
Number (in shares)	405,130
Weighted-Average Exercise Price (in dollars per share)	$19
Weighted-Average Remaining Contractual Life	10 months 10 days
Options Exercisable
Number (in shares)	405,130

Stock_Incentive_Plans_Details_2

Stock Incentive Plans (Details 4) (USD $)	0 Months Ended	12 Months Ended
In Millions, except Share data, unless otherwise specified	Jun. 23, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 23, 2014
Weighted-Average Grant Date Fair Value
Issuance of treasury shares in conjunction with units vested		18,618	111,012	6,804
Additional disclosures
Amount of compensation cost to be recognized		$3.60
Period over which cost will be recognized		3 years 7 months 6 days
Compensation expense recognized		1.2	1.1	1
Restricted stock units
Stock Incentive Plans
Number of shares of common stock per award		1
Shares
Non-vested at beginning of year (in shares)		919,928	736,412	455,352
Reclass to DSUs		-4,960
Granted (in shares)		304,277	351,452	266,258
Dividend Equivalents Earned (in shares)		35,166	17,211	32,704
Vested (in shares)		-26,432	-156,795	-9,925
Forfeited (in shares)		-44,109	-28,352	-7,977
Non-vested at end of period (in shares)		1,183,870	919,928	736,412
Weighted-Average Grant Date Fair Value
Non-vested at beginning of year (in dollars per share)		$4.97	$4.92	$4.98
Reclass to DSUs		$5.04
Granted (in dollars per share)		$5.84	$5.02	$4.83
Dividend Equivalents Earned (in dollars per share)		$5.62	$4.86	$4.79
Vested (in dollars per share)		$4.82	$4.84	$4.19
Forfeited (in dollars per share)		$4.73	$5.14	$5.15
Non-vested at end of period (in dollars per share)		$5.22	$4.97	$4.92
Issuance of treasury shares in conjunction with units vested		18,618	111,012
Additional disclosures
Compensation expense recognized		0
Restricted stock units | Minimum
Stock Incentive Plans
Requisite service period		1 year
Restricted stock units | Maximum
Stock Incentive Plans
Requisite service period		5 years
Restricted stock units | Members of management
Shares
Granted (in shares)	304,277
Additional disclosures
Stock price (in dollars per share)	$5.84				$5.84
Amount of compensation cost to be recognized	1.8				1.8
Vesting rights of shares granted (as a percent)	100.00%
Restricted stock units | Members of management | Minimum
Additional disclosures
Period over which cost will be recognized	2 years
Restricted stock units | Members of management | Maximum
Additional disclosures
Period over which cost will be recognized	5 years
DSUs
Stock Incentive Plans
Requisite service period		1 year
DSUs | Directors
Stock Incentive Plans
Number of shares of common stock per award		1
Requisite service period	1 year
Shares
Non-vested at beginning of year (in shares)		29,054	32,991	22,771
Reclass from RSUs		4,960
Granted (in shares)	36,000	49,699	28,800	31,897
Dividend Equivalents Earned (in shares)		4,042	1,636	2,252
Vested (in shares)		-32,011	-34,373	-23,929
Non-vested at end of period (in shares)		55,745	29,054	32,991
Outstanding at end of period (in shares)		146,057	87,356	56,920
Weighted-Average Grant Date Fair Value
Non-vested at beginning of year (in dollars per share)		$5.05	$4.77	$5.23
Reclass from RSUs		$5.04
Granted (in dollars per share)		$5.84	$5.04	$4.77
Dividend Equivalents Earned (in dollars per share)		$5.63	$5.03	$4.76
Vested (in dollars per share)		$5.10	$4.77	$5.21
Non-vested at end of period (in dollars per share)		$5.77	$5.05	$4.77
Outstanding at end of period (in dollars per share)		$5.34	$5.06	$4.96
Additional disclosures
Stock price (in dollars per share)	$5.84				$5.84
Amount of compensation cost to be recognized	0.2				0.2
Vesting rights of shares granted (as a percent)	100.00%
Settlement period		30 days
DSUs | Chairman of the board
Shares
Granted (in shares)	13,699
Additional disclosures
Amount of compensation cost to be recognized	$0.10				$0.10
Period over which cost will be recognized	5 years

Transactions_with_Directors_an2

Transactions with Directors and Executive Officers (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
Analysis of the changes in loans to related parties
Balance at beginning of year	$30,105,000
Addition due to change in relationship	8,393,000
Deletion due to change in relationship	-40,000
New loans/ advances	50,576,000
Repayments	-51,584,000
Balance at end of year	37,450,000
Directors and executive officers
Analysis of the changes in loans to related parties
Total unused commitments	$22,600,000

Commitments_Contingencies_and_2

Commitments, Contingencies and Credit Risk (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Credit Commitments and Contingencies
Liabilities for potential obligations under guarantees	$0	$0
Lease Commitments
Rent expense under operating leases	1,500,000	1,600,000	2,500,000
Projected minimum rental payments under the terms of leases
2015	941,000
2016	219,000
2017	111,000
2018	102,000
2019	70,000
Total	1,443,000
Commitments to extend credit
Credit Commitments and Contingencies
Financial instruments whose contract amounts represent credit risk	561,439,000	527,614,000
Standby letters of credit
Credit Commitments and Contingencies
Financial instruments whose contract amounts represent credit risk	$20,466,000	$10,155,000
Maximum
Credit Commitments and Contingencies
Term for guarantee	1 year

Derivative_Financial_Instrumen2

Derivative Financial Instruments (Details) (USD $)	Dec. 31, 2014
Derivative Financial Instruments
Foreign loan balance, gross	$1,800,000
Foreign currency forward contracts | Not designated as hedging
Derivative Financial Instruments
Notional amount	1,781,000
Foreign currency forward contracts | Not designated as hedging | Other assets.
Derivative Financial Instruments
Estimated fair value	$15,000

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fair Value Measurements
Transfers between levels of fair value hierarchy	$0
Financial assets and financial liabilities measured at fair value
Securities available for sale	759,065	841,310
Impaired loans	26,586	34,060
OREO	216	2,133
U.S. Treasury securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	50,606	102,640
Obligations of U.S. government corporations and agencies
Financial assets and financial liabilities measured at fair value
Securities available for sale	167,010	257,411
Obligations of states and political subdivisions
Financial assets and financial liabilities measured at fair value
Securities available for sale	220,161	272,152
Residential mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	235,636	177,735
Corporate debt securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	79,307	25,506
Mutual funds and other equity securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	6,345	5,866
Recurring basis | Level 1 Inputs | Mutual funds and other equity securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	6,345	5,866
Recurring basis | Level 2 | Foreign currency forward contracts
Financial assets and financial liabilities measured at fair value
Derivative assets	15
Recurring basis | Level 2 | U.S. Treasury securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	50,606	102,640
Recurring basis | Level 2 | Obligations of U.S. government corporations and agencies
Financial assets and financial liabilities measured at fair value
Securities available for sale	167,010	257,411
Recurring basis | Level 2 | Obligations of states and political subdivisions
Financial assets and financial liabilities measured at fair value
Securities available for sale	220,161	272,152
Recurring basis | Level 2 | Residential mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	235,636	177,735
Recurring basis | Level 2 | Corporate debt securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	79,307	25,506
Recurring basis | Fair Value | Foreign currency forward contracts
Financial assets and financial liabilities measured at fair value
Derivative assets	15
Recurring basis | Fair Value | U.S. Treasury securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	50,606	102,640
Recurring basis | Fair Value | Obligations of U.S. government corporations and agencies
Financial assets and financial liabilities measured at fair value
Securities available for sale	167,010	257,411
Recurring basis | Fair Value | Obligations of states and political subdivisions
Financial assets and financial liabilities measured at fair value
Securities available for sale	220,161	272,152
Recurring basis | Fair Value | Residential mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	235,636	177,735
Recurring basis | Fair Value | Corporate debt securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	79,307	25,506
Recurring basis | Fair Value | Mutual funds and other equity securities
Financial assets and financial liabilities measured at fair value
Securities available for sale	6,345	5,866
Non-recurring basis | Level 3
Financial assets and financial liabilities measured at fair value
Impaired loans	2,129	5,491
OREO		1,134
Non-recurring basis | Fair Value
Financial assets and financial liabilities measured at fair value
Impaired loans	2,129	5,491
OREO		$1,134

Fair_Value_Measurements_Detail1

Fair Value Measurements (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Quantitative Information about Level 3 Fair Value Measurements
Impaired loans	26,586	34,060
OREO	216	2,133
Non-recurring basis | Level 3
Quantitative Information about Level 3 Fair Value Measurements
Impaired loans	2,129	5,491
OREO		1,134
Non-recurring basis | Level 3 | Appraisal of collateral | Impaired loans
Quantitative Information about Level 3 Fair Value Measurements
Impaired loans	2,129	5,491
Non-recurring basis | Level 3 | Appraisal of collateral | Impaired loans | Minimum
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)	-7.70%	-0.40%
Non-recurring basis | Level 3 | Appraisal of collateral | Impaired loans | Maximum
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)	-54.30%	-36.00%
Non-recurring basis | Level 3 | Appraisal of collateral | Impaired loans | Weighted Average
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)	-100.00%	-100.00%
Non-recurring basis | Level 3 | Appraisal of collateral | OREO
Quantitative Information about Level 3 Fair Value Measurements
OREO		1,134
Non-recurring basis | Level 3 | Appraisal of collateral | OREO | Minimum
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)		-6.60%
Non-recurring basis | Level 3 | Appraisal of collateral | OREO | Maximum
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)		-47.90%
Non-recurring basis | Level 3 | Appraisal of collateral | OREO | Weighted Average
Quantitative Information about Level 3 Fair Value Measurements
Appraisal adjustments (as a percent)		-100.00%

Fair_Value_Measurements_Detail2

Fair Value Measurements (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financial assets:
Cash and due from banks	$339,438	$231,603
Securities held to maturity	2,425	831
Loans, net	2,357,837	2,233,893
Financial liabilities:
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Carrying Amount | Level 2
Financial assets:
Cash and due from banks	339,438	231,603
Securities held to maturity	2,373	834
Loans held for sale	10,400	13,840
Accrued interest receivable	11,187	11,148
Financial liabilities:
Deposits	2,900,848	2,869,138
Securities sold under agreements to repurchase	198,893	172,348
Long-term debt	50,000
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Accrued interest payable	507	673
Carrying Amount | Level 3
Financial assets:
Loans, net	2,357,837	2,233,893
Fair Value | Level 2
Financial assets:
Cash and due from banks	339,438	231,603
Securities held to maturity	2,425	831
Loans held for sale	10,634	14,103
Accrued interest receivable	11,187	11,148
Financial liabilities:
Deposits	2,900,763	2,870,870
Securities sold under agreements to repurchase	198,893	172,348
Long-term debt	50,000
Junior subordinated debt owed to unconsolidated trusts	55,000	55,000
Accrued interest payable	507	673
Fair Value | Level 3
Financial assets:
Loans, net	$2,360,000	$2,236,841

Reportable_Segments_and_Relate2

Reportable Segments and Related Information (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
									item
Reportable Segments and Related Information
Number of reportable segments									3
Reportable Segments and Related Information
Goodwill	$20,686				$20,686				$20,686	$20,686
Total Assets	3,665,607				3,539,575				3,665,607	3,539,575
Interest income:	27,657	27,511	26,656	26,251	26,885	27,236	27,460	27,115	108,075	108,696	116,916
Interest expense:	1,570	1,600	1,635	1,694	1,881	2,003	2,215	2,532	6,499	8,631	14,770
Other income:	14,739	14,204	15,012	14,986	14,529	15,630	15,783	16,641	58,941	62,583	66,852
Net Income:	7,593	9,109	8,185	7,887	6,920	7,933	7,440	6,433	32,774	28,726	22,357
FirsTech
Reportable Segments and Related Information
Goodwill	8,992				8,992				8,992	8,992
Busey Wealth Management
Reportable Segments and Related Information
Goodwill	11,694				11,694				11,694	11,694
Operating segments | Busey Bank
Reportable Segments and Related Information
Total Assets	3,589,419				3,456,555				3,589,419	3,456,555
Interest income:									107,766	108,413	116,608
Interest expense:									5,355	7,448	13,466
Other income:									32,452	36,774	39,908
Net Income:									30,764	25,416	19,162
Operating segments | FirsTech
Reportable Segments and Related Information
Goodwill	8,992				8,992				8,992	8,992
Total Assets	28,540				27,253				28,540	27,253
Interest income:									52	51	62
Other income:									9,561	8,541	8,522
Net Income:									1,227	1,000	935
Operating segments | Busey Wealth Management
Reportable Segments and Related Information
Goodwill	11,694				11,694				11,694	11,694
Total Assets	31,196				28,548				31,196	28,548
Interest income:									287	242	251
Other income:									18,953	17,799	16,345
Net Income:									4,681	4,242	3,363
All other
Reportable Segments and Related Information
Total Assets	16,452				27,219				16,452	27,219
Interest income:									-30	-10	-5
Interest expense:									1,144	1,183	1,304
Other income:									-2,025	-531	2,077
Net Income:									($3,898)	($1,932)	($1,103)

Acquisitions_Details

Acquisitions (Details) (USD $)	12 Months Ended	0 Months Ended
	Dec. 31, 2014	Jan. 08, 2015	Dec. 31, 2013
Business Acquisition
Consolidated assets	$3,665,607,000		$3,539,575,000
Total gross loans	2,415,690,000		2,295,300,000
Total deposits	2,900,848,000		2,869,138,000
Herget Financial and Herget Bank
Business Acquisition
Business acquisition expenses	400,000
Herget Financial and Herget Bank | Subsequent event
Business Acquisition
Percentage of outstanding common stock to be acquired		100.00%
Aggregate cash consideration		34,100,000
Per share cash consideration entitled (in dollars per share)		588
Maximum period of measurement adjustments from the closing date of acquisition		1 year
Herget Bank | Subsequent event
Business Acquisition
Number of branches		3
Herget Financial and Herget Bank
Business Acquisition
Consolidated assets	278,800,000
Total investments	113,000,000
Total gross loans	112,600,000
Total deposits	$246,400,000

Parent_Company_Only_Financial_2

Parent Company Only Financial Information (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
ASSETS
Cash and due from subsidiary banks	$339,438	$231,603
Securities available for sale	759,065	841,310
Investments in subsidiaries:
Premises and equipment, net	63,974	65,827
Other assets	41,288	43,562
Total assets	3,665,607	3,539,575
Liabilities:
Junior subordinated debentures owed to unconsolidated Trusts	55,000	55,000
Other liabilities	27,227	27,725
Total liabilities	3,231,968	3,124,211
Total stockholders' equity	433,639	415,364	408,797	409,267
Total liabilities and stockholders' equity	3,665,607	3,539,575
Parent
ASSETS
Cash and due from subsidiary banks	84,537	42,645
Securities available for sale	201	201
Investments in subsidiaries:
Bank	373,773	400,442
Non-bank	28,348	25,646
Premises and equipment, net	523	521
Other assets	8,684	9,450
Total assets	496,066	478,905
Liabilities:
Junior subordinated debentures owed to unconsolidated Trusts	55,000	55,000
Other liabilities	7,427	8,541
Total liabilities	62,427	63,541
Total stockholders' equity	433,639	415,364
Total liabilities and stockholders' equity	$496,066	$478,905

Parent_Company_Only_Financial_3

Parent Company Only Financial Information (Details 2) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Dividends from subsidiaries:
Other income	$14,739	$14,204	$15,012	$14,986	$14,529	$15,630	$15,783	$16,641	$58,941	$62,583	$66,852
Expense:
Interest expense:	1,570	1,600	1,635	1,694	1,881	2,003	2,215	2,532	6,499	8,631	14,770
Income tax benefit	-4,763	-4,708	-4,025	-4,038	-3,528	-3,572	-3,787	-3,224	-17,534	-14,111	-10,497
Distributions less than net income of subsidiaries:
Net income	7,593	9,109	8,185	7,887	6,920	7,933	7,440	6,433	32,774	28,726	22,357
Parent
Dividends from subsidiaries:
Non-bank									2,000	2,000	2,500
Interest and dividend income									20	46	49
Other income									3,475	4,669	6,231
Total operating income									5,495	6,715	8,780
Expense:
Salaries and employee benefits									6,778	5,139	4,718
Interest expense:									1,183	1,220	1,351
Operating expense									2,563	2,163	2,469
Total expense									10,524	8,522	8,538
(Loss) income before income tax benefit and distributions less than net income of subsidiaries									-5,029	-1,807	242
Income tax benefit									3,131	1,875	1,155
(Loss) income before distributions less than net income of subsidiaries									-1,898	68	1,397
Distributions less than net income of subsidiaries:
Bank									31,991	26,416	20,097
Non-bank									2,681	2,242	863
Net income									$32,774	$28,726	$22,357

Parent_Company_Only_Financial_4

Parent Company Only Financial Information (Details 3) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows from Operating Activities
Net income	$7,593	$9,109	$8,185	$7,887	$6,920	$7,933	$7,440	$6,433	$32,774	$28,726	$22,357
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization									8,456	8,598	8,759
Stock-based compensation									1,187	1,079	991
Fair value adjustment on employee stock ownership plan shares allocated											-322
Changes in assets and liabilities:
Decrease (increase) in other assets									2,274	9,880	8,368
(Decrease) increase in other liabilities									-650	-63	992
Net cash provided by operating activities									68,111	98,153	49,069
Cash Flows from Investing Activities
Decrease in loans									-126,604	-258,366	-33,680
Proceeds from sales of premises and equipment									78	2,856	77
Purchases of premises and equipment									-3,778	-2,549	-8,611
Net cash used in investing activities									-51,262	-118,698	-204,435
Cash Flows from Financing Activities
Value of shares surrendered upon vesting of restricted stock units to cover tax obligations									-45	-237
Cash dividends paid									-17,224	-14,040	-24,427
Net cash provided by (used in) financing activities									90,986	-99,107	191,568
Cash and due from banks, beginning				231,603				351,255	231,603	351,255	315,053
Cash and due from banks, ending	339,438				231,603				339,438	231,603	351,255
Parent
Cash Flows from Operating Activities
Net income									32,774	28,726	22,357
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization									112	100	98
Distributions less than net income of subsidiaries									-34,672	-28,658	-20,960
Stock-based compensation									1,187	1,079	991
Fair value adjustment on employee stock ownership plan shares allocated											-322
Changes in assets and liabilities:
Decrease (increase) in other assets									951	-62	125
(Decrease) increase in other liabilities									-1,077	381	1,435
Net cash provided by operating activities									-725	1,566	3,724
Cash Flows from Investing Activities
Decrease in loans										68	95
Proceeds from sales of premises and equipment										226
Purchases of premises and equipment									-114	-90	-11
Net cash used in investing activities									-114	204	84
Cash Flows from Financing Activities
Proceeds from charter amendment with subsidiary bank									60,000	50,000
Value of shares surrendered upon vesting of restricted stock units to cover tax obligations									-45	-237
Cash dividends paid									-17,224	-14,040	-24,427
Net cash provided by (used in) financing activities									42,731	35,723	-24,427
Net increase (decrease) in cash and due from subsidiary banks									41,892	37,493	-20,619
Cash and due from banks, beginning				42,645				5,152	42,645	5,152	25,771
Cash and due from banks, ending	$84,537				$42,645				$84,537	$42,645	$5,152

Unaudited_Interim_Financial_Da2

Unaudited Interim Financial Data (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Unaudited Interim Financial Data
Interest income:	$27,657	$27,511	$26,656	$26,251	$26,885	$27,236	$27,460	$27,115	$108,075	$108,696	$116,916
Interest expense:	1,570	1,600	1,635	1,694	1,881	2,003	2,215	2,532	6,499	8,631	14,770
Net interest income	26,087	25,911	25,021	24,557	25,004	25,233	25,245	24,583	101,576	100,065	102,146
Provision for loan losses			1,000	1,000	1,500	2,000	2,000	2,000	2,000	7,500	16,500
Other income:	14,739	14,204	15,012	14,986	14,529	15,630	15,783	16,641	58,941	62,583	66,852
Non-interest expense	28,470	26,298	26,823	26,618	27,585	27,358	27,801	29,567	108,209	112,311	119,644
Income before income taxes	12,356	13,817	12,210	11,925	10,448	11,505	11,227	9,657	50,308	42,837	32,854
Income taxes	4,763	4,708	4,025	4,038	3,528	3,572	3,787	3,224	17,534	14,111	10,497
Net income	7,593	9,109	8,185	7,887	6,920	7,933	7,440	6,433	32,774	28,726	22,357
Preferred stock dividends	182	182	181	182	908	909	908	908	727	3,633	3,633
Net income available for common stockholders	$7,411	$8,927	$8,004	$7,705	$6,012	$7,024	$6,532	$5,525	$32,047	$25,093	$18,724
Basic earnings per share (in dollars per share)	$0.08	$0.10	$0.09	$0.09	$0.07	$0.08	$0.08	$0.06	$0.37	$0.29	$0.22
Diluted earnings per share (in dollars per share)	$0.08	$0.10	$0.09	$0.09	$0.07	$0.08	$0.08	$0.06	$0.37	$0.29	$0.22