MidWestOne Financial (MOFG) 10-K 2 Mar 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Mar. 01, 2017	Jun. 30, 2016
Entity Information [Line Items]
Entity Registrant Name	MIDWESTONE FINANCIAL GROUP, INC.
Entity Central Index Key	1,412,665
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Public Float			$ 243.7
Entity Common Stock, Shares Outstanding		11,459,521

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Assets:
Cash and due from banks	$ 41,464	$ 44,199
Interest-bearing deposits in banks	1,764	2,731
Federal funds sold	0	167
Cash and cash equivalents	43,228	47,097
Investment securities:
Available for sale	477,518	427,241
Held to maturity (fair value of $164,792 as of December 31, 2016 and $118,234 as of December 31, 2015)	168,392	118,423
Loans held for sale	4,241	3,187
Loans	2,165,143	2,151,942
Allowance for loan losses	(21,850)	(19,427)
Net loans	2,143,293	2,132,515
Premises and equipment, net	75,043	76,202
Accrued interest receivable	13,871	13,736
Goodwill	64,654	64,548
Other intangible assets, net	15,171	19,141
Bank-owned life insurance	47,231	46,295
Other real estate owned	2,097	8,834
Deferred income taxes	6,523	947
Other assets	18,313	21,809
Total assets	3,079,575	2,979,975
Deposits:
Non-interest-bearing demand	494,586	559,586
Interest-bearing checking	1,136,282	1,064,350
Savings	197,698	189,489
Certificates of deposit under $100,000	326,832	348,268
Certificates of deposit $100,000 and over	325,050	301,828
Total deposits	2,480,448	2,463,521
Federal funds purchased	35,684	1,500
Securities sold under agreements to repurchase	82,187	67,463
Federal Home Loan Bank borrowings	115,000	87,000
Junior subordinated notes issued to capital trusts	23,692	23,587
Long-term debt	17,500	22,500
Deferred compensation liability	5,180	5,132
Accrued interest payable	1,472	1,507
Other liabilities	12,956	11,587
Total liabilities	2,774,119	2,683,797
Commitments and contingencies (Note 18)
Shareholders' Equity:
Preferred stock, no par value; authorized 500,000 shares; no shares issued and outstanding at December 31, 2016 and December 31, 2015	0	0
Common stock, $1.00 par value; authorized 15,000,000 shares at December 31, 2016 and December 31, 2015; issued 11,713,481 shares at December 31, 2016 and at December 31, 2015; outstanding 11,436,360 shares at December 31, 2016 and 11,408,773 shares at December 31, 2015	11,713	11,713
Additional paid-in capital	163,667	163,487
Treasury stock at cost, 277,121 shares as of December 31, 2016 and 304,708 shares at December 31, 2015	(5,766)	(6,331)
Retained earnings	136,975	123,901
Accumulated other comprehensive income	(1,133)	3,408
Total shareholders’ equity	305,456	296,178
Total liabilities and shareholders’ equity	$ 3,079,575	$ 2,979,975

Consolidated Balance Sheets Par

Consolidated Balance Sheets Parenthetical Parentheticals - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Estimated fair value of investment securities held to maturity	$ 164,792	$ 118,234
Shareholders' equity:
Preferred stock, par value	$ 0	$ 0
Preferred stock, shares authorized	500,000	500,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	15,000,000	15,000,000
Common stock, shares issued	11,713,481	11,713,481
Common stock, shares outstanding	11,436,360	11,408,773
Shares of Treasury stock	277,121	304,708

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest income:
Interest and fees on loans	$ 98,162	$ 86,544	$ 48,466
Interest and discount on loan pool participations		798	1,516
Interest on bank deposits	161	70	38
Interest on federal funds sold	5	1	8
Interest on investment securities:
Taxable securities	8,297	7,734	8,921
Tax-exempt securities	5,703	5,553	5,455
Total interest income	112,328	100,700	64,404
Interest expense:
Interest-bearing checking	3,151	2,627	2,168
Savings	267	360	145
Certificates of deposit under $100,000	2,929	2,445	2,701
Certificates of deposit $100,000 and over	3,032	2,406	2,013
Total interest expense on deposits	9,379	7,838	7,027
Interest on federal funds purchased	47	34	8
Interest on securities sold under agreements to repurchase	158	176	119
Interest on Federal Home Loan Bank borrowings	1,827	1,451	2,092
Interest on other borrowings	19	22	24
Interest on junior subordinated notes issued to capital trusts	825	592	281
Interest on subordinated notes	0	162	0
Interest on long-term debt	467	373	0
Total interest expense	12,722	10,648	9,551
Net interest income	99,606	90,052	54,853
Provision for loan losses	7,983	5,132	1,200
Net interest income after provision for loan losses	91,623	84,920	53,653
Noninterest income:
Trust, investment, and insurance fees	5,574	6,005	5,771
Service charges and fees on deposit accounts	5,219	4,401	3,279
Loan origination and servicing fees	3,771	2,756	1,554
Other service charges and fees	5,951	5,215	2,307
Bank-owned life insurance income	1,366	1,307	1,102
Gain on sale or call of available for sale securities	464	1,011	1,227
Loss on sale of premises and equipment	(44)	(29)	(1)
Other gain	1,133	527	74
Total noninterest income	23,434	21,193	15,313
Noninterest expense:
Salaries and employee benefits	49,621	41,865	24,918
Net occupancy and equipment expense	13,066	9,975	6,293
Professional fees	4,216	4,929	3,606
Data processing expense	4,940	2,659	1,565
FDIC Insurance expense	1,563	1,397	964
Amortization of intangible assets	3,970	3,271	547
Other operating expense	10,430	9,080	5,520
Total noninterest expense	87,806	73,176	43,413
Income before income tax expense	27,251	32,937	25,553
Income tax expense	6,860	7,819	7,031
Net income	$ 20,391	$ 25,118	$ 18,522
Earnings per share:
Earnings per share, basic	$ 1.78	$ 2.42	$ 2.20
Earnings per share, diluted	$ 1.78	$ 2.42	$ 2.19

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net income	$ 20,391	$ 25,118	$ 18,522
Other comprehensive income, available for sale securities:
Unrealized holding gains (losses) arising during period	(6,906)	(2,046)	8,114
Reclassification adjustment for gains included in net income	(464)	(1,011)	(1,227)
Income tax expense (benefit)	(2,829)	(1,143)	2,614
Other comprehensive income (loss) on available for sale securities	(4,541)	(1,914)	4,273
Total other comprehensive income (loss)	(4,541)	(1,914)	4,273
Comprehensive income	$ 15,850	$ 23,204	$ 22,795

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2013	$ 178,016	$ 0	$ 8,690	$ 80,506	$ (3,702)	$ 91,473	$ 1,049
Net income	18,522					18,522
Dividends paid on common stock	(4,868)					(4,868)
Stock options exercised	259			(26)	285
Release/lapse of restriction on RSUs	23			(436)	459
Repurchase of common stock	(3,987)				(3,987)
Stock compensation	493			493
Other comprehensive Income (loss), net of tax	4,273						4,273
Balance at Dec. 31, 2014	192,731	0	8,690	80,537	(6,945)	105,127	5,322
Net income	25,118					25,118
Issuance of common stock due to business combination (2,723,083 shares)	77,895		2,723	75,172
Issuance of common stock - private placement (300,000 shares), net of expenses	7,900		300	7,600
Dividends paid on common stock	(6,344)					(6,344)
Stock options exercised	129			(40)	169
Release/lapse of restriction on RSUs	29			(416)	445
Stock compensation	634			634
Other comprehensive Income (loss), net of tax	(1,914)						(1,914)
Balance at Dec. 31, 2015	296,178	0	11,713	163,487	(6,331)	123,901	3,408
Net income	20,391					20,391
Dividends paid on common stock	(7,317)					(7,317)
Stock options exercised	38			(22)	60
Release/lapse of restriction on RSUs	(24)			(529)	505
Stock compensation	731			731
Other comprehensive Income (loss), net of tax	(4,541)						(4,541)
Balance at Dec. 31, 2016	$ 305,456	$ 0	$ 11,713	$ 163,667	$ (5,766)	$ 136,975	$ (1,133)

Consolidated Statements of Sha7

Consolidated Statements of Shareholders' Equity Parenthetical Parentheticals - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Dividends paid on common stock (per share)	$ 0.64	$ 0.60	$ 0.58
Common Stock
Issuance of common stock due to business combination (shares)	0	2,723,083	0
Issuance of common stock - private placement (shares)	0	300,000	0
Stock options exercised (shares)	2,900	8,414	15,419
Release/lapse of restriction on RSUs (shares)	26,133	23,123	27,491
Repurchase of common stock (shares)	0	0	165,766

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income	$ 8,238	$ 20,391	$ 25,118	$ 18,522
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	1,490	7,983	5,132	1,200
Depreciation of premises and equipment		4,555	3,284	2,174
Amortization of other intangibles		3,970	3,271	547
Amortization of premiums and discounts on investment securities, net		1,624	1,833	1,505
Loss on sale of premises and equipment		44	29	1
Deferred income tax expense (benefit)		(2,853)	1,300	2,502
Stock based compensation		731	634	493
Net gain on sale or call of available for sale securities		(464)	(1,011)	(1,227)
Net gain on sale of other real estate owned		(795)	(332)	(74)
Net gain on sale of loans held for sale		(2,475)	(1,794)	(507)
Writedown of other real estate owned		675	0	66
Origination of loans held for sale		132,003	129,129	42,410
Proceeds from sales of loans held for sale		(133,424)	(128,537)	(42,473)
Increase in accrued interest receivable		(135)	(167)	(489)
Increase in cash value of bank-owned life insurance		(1,366)	(1,307)	(1,102)
Decrease in other assets		3,496	3,037	485
(Decrease) increase in deferred compensation liability		48	83	(76)
(Decrease) increase in accounts payable, accrued expenses, and other liabilities		1,334	(5,810)	(819)
Net cash provided by operating activities		38,184	32,708	23,264
Cash flows from investing activities
Proceeds from sales of available for sale investment securities		23,381	116,829	33,457
Proceeds from maturities and calls of available for sale securities		84,612	70,806	64,669
Purchase of available for sale investment securities		(166,618)	(25,424)	(67,892)
Proceeds from maturities and calls of held to maturity securities		12,080	4,669	1,147
Purchases of held to maturity securities		(62,231)	(29,182)	(20,052)
Increase in loans		(20,648)	(106,278)	(45,911)
Decrease in loan pool participations, net		0	19,332	6,201
Purchase of premises and equipment, net		(5,634)	(14,869)	(12,320)
Proceeds from sale of other real estate owned		8,744	3,594	650
Proceeds from sales of premises and equipment		2,299	1,132	57
Proceeds of principal and earnings from bank-owned life insurance		430	0	488
Purchases of bank-owned life insurance		0	0	(7,930)
Net cash paid in business acquisition (Note 2)		0	35,596	0
Net cash provided by (used in) investing activities		(123,585)	5,013	(47,436)
Cash flows from financing activities:
Net increase in deposits		16,927	5,812	33,600
Net increase (decrease) in federal funds purchased		34,184	(15,908)	11,926
Net increase (decrease) in securities sold under agreements to repurchase		14,724	(9,482)	(362)
Proceeds from Federal Home Loan Bank borrowings		50,000	24,000	26,000
Repayment of Federal Home Loan Bank borrowings		(22,000)	(30,000)	(39,900)
Proceeds and effect of tax from share-based compensation		14	158	282
Redemption of subordinated note		0	12,669	0
Proceeds from long-term debt		0	25,000	0
Payments on long-term debt		5,000	2,500	0
Dividends paid		(7,317)	(6,344)	(4,868)
Issuance of common stock, net of expenses		0	7,900	0
Repurchase of common stock		0	0	(3,987)
Net cash provided by (used in) financing activities		81,532	(14,033)	22,691
Net increase (decrease) in cash and cash equivalents		(3,869)	23,688	(1,481)
Cash and cash equivalents:
Cash and cash equivalents at beginning of period		47,097	23,409	24,890
Cash and cash equivalents at end of period	47,097	43,228	47,097	23,409
Supplemental disclosures of cash flow information:
Cash paid during the period for interest		12,757	10,004	9,453
Cash paid during the period for income taxes		7,957	7,677	4,144
Supplemental schedule of non-cash investing activities:
Transfer of loans to other real estate owned		1,887	1,760	$ 788
Noncash assets acquired:
Goodwill	64,548	64,654	64,548
Central Bancshares, Inc.
Noncash assets acquired:
Investment securities	160,775		160,775
Loans	916,973		916,973
Premises and equipment	27,908		27,908
Goodwill	64,654		64,654
FDIC indemnification asset	3,753		3,753
Other real estate owned	8,420		8,420
Other assets	14,482		14,482
Total noncash assets acquired	1,211,118		1,211,118
Liabilities assumed:
Deposits	1,049,167		1,049,167
Short-term borrowings	16,124		16,124
Junior subordinated notes issued to capital trusts	8,050		8,050
Subordinated notes payable	12,669		12,669
Other liabilities	11,617		11,617
Total liabilities assumed	1,097,627		1,097,627
Core Deposits
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of other intangibles		3,634	2,984
Core Deposits | Central Bancshares, Inc.
Noncash assets acquired:
Finite lived intangible	12,773		12,773
Trade Names
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of other intangibles		$ 243	177
Trade Names | Central Bancshares, Inc.
Noncash assets acquired:
Finite lived intangible	$ 1,380		$ 1,380

Nature of Business and Signific

Nature of Business and Significant Accounting Policies (Notes)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block]	Nature of Business and Significant Accounting Policies Nature of business : The Company is a bank holding company registered under the Bank Holding Company Act of 1956 that has elected to be a financial holding company. It is headquartered in Iowa City, Iowa and owns all of the outstanding common stock of MidWest One Bank, Iowa City, and all of the common stock of MidWest One Insurance Services, Inc., Oskaloosa, Iowa. The Bank is also headquartered in Iowa City, Iowa, and provides services to individuals, businesses, governmental units and institutional customers through a total of 43 offices in central and east-central Iowa, the Twin Cities metro area in Minnesota and western Wisconsin. and Naples and Fort Myers, Florida. MidWest One Insurance Services, Inc. provides personal and business insurance services in Cedar Falls, Conrad, Melbourne, Oskaloosa, Parkersburg, and Pella, Iowa. The Bank is actively engaged in many areas of commercial banking, including: acceptance of demand, savings and time deposits; making commercial, real estate, agricultural and consumer loans, and other banking services tailored for its individual customers. The wealth management area of the Bank administers estates, personal trusts, and conservatorships accounts along with providing other management services to customers. On May 1, 2015, we consummated a merger with Central Bancshares, Inc., a Minnesota corporation. In connection with the merger, Central Bank, a Minnesota-chartered commercial bank and wholly-owned subsidiary of Central, became a wholly-owned subsidiary of MidWest One . Central Bank has operated, since 1988, as a community bank and has strong roots in the communities it serves. Per the merger agreement, each of the outstanding shares of Central common stock was converted into the pro rata portion of 2,723,083 shares of Company common stock and $64.0 million in cash. (See Note 2. “Business Combination” for additional information.) On April 2, 2016, Central Bank merged with and into the Bank. Accounting estimates : The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amount of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The U.S. economic environment in recent years has increased the degree of uncertainty inherent in these estimates. Certain significant estimates : The allowance for loan losses, fair value of assets acquired and liabilities assumed in a business combination, annual impairment testing of goodwill, and the fair values of investment securities and other financial instruments involve certain significant estimates made by management. These estimates are reviewed by management routinely, and it is reasonably possible that circumstances that exist may change in the near-term future and that the effect could be material to the consolidated financial statements. Principles of consolidation : The consolidated financial statements include the accounts of MidWest One Financial Group, Inc., a bank holding company, and its wholly-owned subsidiary MidWest One Bank, which is a state chartered bank whose primary federal regulator is the FDIC, and MidWest One Insurance Services, Inc. All significant inter-company accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior periods’ consolidated financial statements to present them on a basis comparable with the current period’s consolidated financial statements. Trust assets, other than cash deposits held by the Bank in a fiduciary or agency capacity for its customers, are not included in the accompanying consolidated financial statements because such accounts are not assets of the the Bank. In the normal course of business, the Company may enter into a transaction with a variable interest entity (“VIE”). VIEs are legal entities whose investors lack the ability to make decisions about the entity’s activities, or whose equity investors do not have the right to receive the residual returns of the entity. The applicable accounting guidance requires the Company to perform ongoing quantitative and qualitative analysis to determine whether it must consolidate any VIE. The Company does not have any ownership interest in or exert any control over any VIE, and thus no VIEs are included in the consolidated financial statements. Investments in non-marketable loan participation certificates for which the Company does not have the ability to exert significant influence are accounted for using the cost method. Presentation of cash flows : For purposes of reporting cash flows, cash and due from banks includes cash on hand, amounts due from banks, and federal funds sold. Cash flows from portfolio loans originated by the Bank, deposits, federal funds purchased, and securities sold under agreements to repurchase are reported net. Cash receipts and cash payments resulting from acquisitions and sales of loans originated for sale are classified as operating cash flows on a gross basis in the consolidated statements of cash flows. The nature of the Company’s business requires that it maintain amounts due from banks that, at times, may exceed federally insured limits. In the opinion of management, no material risk of loss exists due to the various correspondent banks financial condition and the fact that they are well capitalized. Investment securities : Certain debt securities that the Company has the positive intent and ability to hold to maturity are classified as held to maturity and recorded at amortized cost. Securities not classified as held to maturity, including equity securities with readily determinable fair values, are classified as available for sale and recorded at fair value, with unrealized gains and losses excluded from earnings and reported in other comprehensive income. The Company employs valuation techniques which utilize observable inputs when those inputs are available. These observable inputs reflect assumptions market participants would use in pricing the security, developed based on market data obtained from sources independent of the Company. When such information is not available, the Company employs valuation techniques which utilize unobservable inputs, or those which reflect the Company’s own assumptions about assumptions that market participants would use, based on the best information available in the circumstances. These valuation methods typically involve cash flow and other financial modeling techniques. Changes in underlying factors, assumptions, estimates, or other inputs to the valuation techniques could have a material impact on the Company’s future financial condition and results of operations. Fair value measurements are required to be classified as Level 1 (quoted prices), Level 2 (based on observable inputs) or Level 3 (based on unobservable inputs) discussed in more detail in Note 20 to the consolidated financial statements. Available for sale securities are recorded at fair value with unrealized gains and losses excluded from earnings and reported as a separate component of shareholders’ equity until realized. Purchase premiums and discounts are recognized in interest income using the interest method over the terms of the securities. Declines in the fair value of held to maturity and available for sale securities below their cost that are deemed to be other than temporary are reflected in earnings as realized losses. In determining whether other than temporary impairment exists, management considers whether: (1) we have the intent to sell the security; (2) it is more likely than not that we will be required to sell the security before recovery of the amortized cost basis; and (3) we do not expect to recover the entire amortized cost basis of the security. Gains and losses on the sale of securities are recorded on the trade date and are determined using the specific identification method. Loans : Loans are stated at the principal amount outstanding, net of deferred loan fees and costs and allowance for loan losses. Interest on loans is credited to income as earned based on the principal amount outstanding. Deferred loan fees and costs are amortized using the level yield method over the remaining maturities on the loans. The accrual of interest on mortgage and commercial loans is discontinued at the time the loan is 120 days past due, unless the credit is well secured and in process of collection. Credit card loans and other personal loans are typically charged off no later than 180 days past due. Past due status is based on contractual terms of the loan. In all cases, loans are placed on nonaccrual or charged off at an earlier date, if collection of principal or interest is considered doubtful. All interest accrued but not collected for loans that are placed on nonaccrual or charged off is reversed against interest income. The interest on these loans is accounted for on the cash-basis or cost-recovery method, until qualifying for return to accrual. Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured. Purchased loans : All purchased loans (nonimpaired and impaired) are initially measured at fair value as of the acquisition date in accordance with applicable authoritative accounting guidance. Credit discounts are included in the determination of fair value. An allowance for loan losses is not recorded at the acquisition date for loans purchased. Individual loans acquired through the completion of a transfer, including loans that have evidence of deterioration of credit quality since origination and for which it is probable, at acquisition, that the Company will be unable to collect all contractually required payments receivable, are referred to herein as “purchased credit impaired loans.” In determining the acquisition date fair value and estimated credit losses of purchased credit impaired loans, and in subsequent accounting, the Company accounts for loans individually. Contractually required payments for interest and principal that exceed the undiscounted cash flows expected at acquisition, or the “nonaccretable difference,” are not recognized as a yield adjustment or as a loss accrual or valuation allowance. Expected cash flows at the purchase date in excess of the fair value of loans, if any, are recorded as interest income over the expected life of the loans if the timing and amount of future cash flows are reasonably estimable. Subsequent to the purchase date, increases in cash flows over those expected at the purchase date are recognized as interest income prospectively. The present value of any decreases in expected cash flows after the purchase date is recognized by recording an allowance for loan losses and a provision for loan losses. If the Company does not have the information necessary to reasonably estimate cash flows to be expected, it may use the cost-recovery method or cash-basis method of income recognition. Subsequent to the purchase date, increases in cash flows over those expected at the purchase date are recognized as interest income prospectively. Subsequent to the purchase date, the methods utilized to estimate the required allowance for loan losses for these loans are similar to originated loans. The remaining differences between the purchase price and the unpaid balance at the date of acquisition are recorded in interest income over the life of the loan. Covered assets and indemnification asset : As part of the Central transaction, the Company assumed loss-share or similar credit protection agreements with the FDIC. Loans and other real estate owned covered under these agreements are reported respectively in loans or other real estate owned. The loss-share assets are measured separately from the loan portfolios because they are not contractually embedded in the loans and are not transferable with the loans should the Company choose to dispose of them. Fair values at the acquisition dates were estimated based on projected collections from the FDIC. When cash flow estimates are adjusted downward for a particular loan, the FDIC indemnification asset is increased and an allowance for loan losses is established . When cash flow estimates are adjusted upward for a particular loan, the FDIC indemnification asset is decreased, the Company accounts for the associated decrease in the indemnification asset by amortizing the change over the lesser of the contractual term of the indemnification agreement or the remaining life of the indemnified asset. When cash flow estimates are adjusted downward for covered foreclosed real estate, the FDIC indemnification asset is increased. When cash flow estimates are adjusted upward for covered foreclosed real estate, the FDIC indemnification asset is decreased. Any write-down after the transfer to covered foreclosed real estate is reversed. In applicable scenarios, the claw-back liability for amounts owed to the FDIC for better than expected performance will increase or decrease accordingly. The related FDIC indemnification assets are included in other assets, and there was no impairment recorded on such assets in 2016 . Loan Pool Participations: In 2010, the Company made the decision to exit the loan pool particpation line of business, and all remaining loan pool participations were sold in June 2015. Loans held for sale : Loans originated and intended for sale in the secondary market 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. Mortgage loans held for sale are generally sold with the mortgage servicing rights retained. Gains or losses on sales of mortgage loans are recognized based on the difference between the selling price plus the value of servicing rights, less the carrying value of the related mortgage loans sold. Allowance for loan losses : The allowance for loan losses is established through a provision for loan losses charged to earnings. Loan losses are charged against the allowance when management believes the uncollectibility of a loan balance is confirmed. Subsequent recoveries, if any, are credited to the allowance. The allowance for loan losses is evaluated on a quarterly basis by management and is based upon management’s periodic review of the collectiblity 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. The allowance consists of specific and general components. The specific component relates to loans that are classified as doubtful, substandard or special mention. For such loans that are also classified as impaired as well as any loan (regardless of classification) meeting the definition of a troubled debt restructuring, an allowance is established when the discounted cash flows (or collateral value or observable market price) of the impaired loan are lower than the carrying value of that loan. The general component covers loans not classified as impaired and is based on historical loss experience adjusted for qualitative factors. A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual 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. Impairment is measured on a loan-by-loan basis by either the present value of 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 loans (with individual balances less than $100,000) are not evaluated for impairment, but are collectively applied a standard allocation under ASC 450. Transfers of financial assets : Revenue from the origination and sale of loans in the secondary market is recognized upon the transfer of financial assets and accounted for as sales when control over the assets has been surrendered. The Company also sells participation interests in some large loans originated, to non-affiliated entities. Control over transferred assets is deemed to be surrendered when: (1) the assets have been isolated from the Company; (2) the transferee has 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 trivial 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. Revenue recognition : Trust fees, deposit account service charges and other fees are recognized when payment is received for the services (cash basis), which generally occurs at the time the services are provided. Credit-related financial instruments : In the ordinary course of business, the Company has entered into commitments to extend credit, including commitments under credit card arrangements, commercial letters of credit and standby letters of credit. Such financial instruments are recorded when they are funded. The Company records a liability to the extent losses on its commitments to lend are probable. Premises and equipment : Land is carried at cost. Premises and equipment are stated at cost less accumulated depreciation. The estimated useful lives and primary method of depreciation for the principal items are as follows: Years Type of Assets Minimum Maximum Depreciation Method Buildings and leasehold improvements 10 - 30 Straight-line Furniture and equipment 3 - 10 Straight-line Charges for maintenance and repairs are expensed as incurred. When assets are retired or disposed of the related cost and accumulated depreciation are removed from the respective accounts and the resulting gain or loss is recorded. Other real estate owned : Real estate properties acquired through or in lieu of foreclosure are initially recorded at fair value less estimated selling cost at the date of foreclosure, establishing a new cost basis. Fair value is determined by management by obtaining appraisals or other market value information at least annually. Any write-downs in value at the date of acquisition are charged to the allowance for loan losses. After foreclosure, valuations are periodically performed by management by obtaining updated appraisals or other market value information. Any subsequent write-downs are recorded as a charge to operations, if necessary, to reduce the carrying value of a property to the updated fair value less estimated selling cost. Net costs related to the holding of properties are included in noninterest expense. Goodwill and other intangibles : Goodwill is the excess of the purchase price over the fair value of identifiable net assets acquired in business combinations accounted for as purchases. Under ASC Topic 350, goodwill of a reporting unit is tested for impairment on an annual basis, or between annual tests if an event occurs or circumstances change that would reduce the fair value of a reporting unit below its carrying amount. The Company's annual assessment is done at the unit level. The Company did not recognize impairment losses during the year ended December 31, 2016 . Any future impairment will be recorded as noninterest expense in the period of assessment. Certain other intangible assets that have finite lives are amortized over the remaining useful lives. Mortgage servicing rights : Mortgage servicing rights are recorded at fair value based on assumptions through a third-party valuation service. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the servicing cost per loan, the discount rate, the escrow float rate, an inflation rate, ancillary income, prepayment speeds and default rates and losses. Bank-owned life insurance : Bank-owned life insurance is carried at cash surrender value, net of surrender and other charges, with increases/decreases reflected as income/expense in the consolidated statements of operations. Employee benefit plans: Deferred benefits under a salary continuation plan are charged to expense during the period in which the participating employees attain full eligibility. Stock-based compensation : Compensation expense for share based awards is recorded over the vesting period at the fair value of the award at the time of grant. The exercise price of options or fair value of nonvested shares granted under the Company’s incentive plans is equal to the fair market value of the underlying stock at the grant date. The Company assumes no projected forfeitures on its stock based compensation, since actual historical forfeiture rates on its stock-based incentive awards has been negligible. Income taxes : The Company and/or its subsidiaries currently file tax returns in all states and local taxing jurisdictions which impose corporate income, franchise or other taxes where it operates. The methods of filing and the methods for calculating taxable and apportionable income vary depending upon the laws of the taxing jurisdiction. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amount of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized. In accordance with ASC 740, Income Taxes , the Company recognizes a tax position as a benefit only if it is more likely than not that the tax position would be sustained in a tax examination, with a tax examination being presumed to occur. The amount recognized is the largest amount of tax benefit that is greater than 50% likely of being realized upon examination. For tax positions not meeting the more likely than not test, no tax benefit is recorded. The Company recognizes interest and/or penalties related to income tax matters in income tax expense. There were no material unrecognized tax benefits or any interest or penalties on any unrecognized tax benefits as of December 31, 2016 and 2015 . Common stock : On July 17, 2014 , the board of directors of the Company approved a new share repurchase program, allowing for the repurchase of up to $5.0 million of stock through December 31, 2016 . The new repurchase program replaced the Company's prior repurchase program, pursuant to which the Company had repurchased approximately $3.7 million of common stock since January 1, 2013. Pursuant to the new program, the Company could continue to repurchase shares from time to time in the open market, and the method, timing and amounts of repurchase were solely in the discretion of the Company's management. The repurchase program did not require the Company to acquire a specific number of shares. Therefore, the amount of shares repurchased pursuant to the program depended on several factors, including market conditions, capital and liquidity requirements, and alternative uses for cash available. In 2014, we repurchased 165,766 shares of common stock at a cost of $4.0 million . In 2015 we repurchased no shares of common stock. Of the $5.0 million of stock authorized under the repurchase plan, $3.8 million remained available for possible future repurchases as of December 31, 2015. No shares were repurchased under this plan during 2016. On July 21, 2016 , the board of directors of the Company approved a share repurchase program, allowing for the repurchase of up to $5.0 million of stock through December 31, 2018 . During 2016 the Company repurchased no common stock under this plan, thus, of the $5.0 million of stock authorized under the repurchase plan, $5.0 million remained available for possible future repurchases as of December 31, 2016 . On May 1, 2015, in connection with the Central merger, the Company issued 2,723,083 shares of its common stock. On June 22, 2015, the Company entered into a Securities Purchase Agreement with certain institutional accredited investors, pursuant to which, on June 23, 2015, the Company sold an aggregate of 300,000 newly issued shares of the Company’s common stock, at a purchase price of $28.00 per share. Each of the purchasers was an existing shareholder of the Company. Comprehensive income : Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income. Certain changes in assets and liabilities, such as unrealized gains and losses on available-for-sale securities, are reported as a separate component of shareholders’ equity on the consolidated balance sheets, and are disclosed in the consolidated statements of comprehensive income. The components of accumulated other comprehensive income, included in shareholders’ equity, net of tax, are as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Unrealized gains on securities available for sale, net of tax $ (1,133 ) $ 3,408 $ 5,322 Accumulated other comprehensive income, net of tax $ (1,133 ) $ 3,408 $ 5,322 Recent Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update No. 2014-09, Revenue from Contract with Customers (Topic 606). The guidance in this update affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets unless those contracts are within the scope of other standards (for example, insurance contracts or lease contracts). The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, an entity should apply the following five steps: 1) identify the contracts(s) with the customer; 2) identify the performance obligations in the contract; 3) determine the transaction price; 4) allocate the transaction price to the performance obligations in the contract; and 5) recognize revenue when (or as) the entity satisfies a performance obligation. The guidance also specifies the accounting for some costs to obtain or fulfill a contract with a customer. For a public entity, the amendments in this update are effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application is not permitted. The adoption of this amendment is not expected to have a significant effect on the Company’s consolidated financial statements. In August 2014, the FASB issued Accounting Standards Update No. 2014-15, Presentation of Financial Statements - Going Concern (Subtopic 205-40): Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The amendments in this update provide guidance in GAAP about management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. In doing so, the amendment should reduce diversity in the timing and content of footnote disclosures. Disclosures are required if it is probable an entity will be unable to meet its obligations within the look-forward period of twelve months after the financial statements are made available. Incremental substantial doubt disclosure is required if the probability is not mitigated by management’s plans. The new standard applies to all entities for the first annual period ending after December 15, 2016, and interim periods thereafter. The adoption of this standard is not expected to have a significant effect on the Company’s consolidated financial statements. In July 2015, the FASB announced a delay to the effective date of Accounting Standards Update No. 2015-09, Revenue from Contract with Customers (Topic 606). Reporting entities may choose to adopt the standard as of the original date, or take advantage of a one-year delay, which the Company intends to take advantage of. For a public entity, the revised effective date is for annual reporting periods beginning after December 15, 2017, including interim periods within that reporting period. Early application is not permitted prior to the original effective date. The adoption of this amendment is not expected to have a significant effect on the Company’s consolidated financial statements. In January 2016, the FASB issued Accounting Standards Update No. 2016-01, Financial Instruments-Overall: Recognition and Measurement of Financial Assets and Financial Liabilities. The guidance in this update makes changes to the current GAAP model primarily affecting the accounting for equity investments, financial liabilities under the fair value option, and the presentation and disclosure requirements for financial instruments. In addition, the FASB clarified guidance related to the valuation allowance assessment when recognizing deferred tax assets resulting from unrealized losses on available-for-sale debt securities. The accounting for other financial instruments, such as loans, investments in debt securities, and financial liabilities is largely unchanged. The treatment of gains and losses for all equity securities, including those without a readily determinable market value, is expected to result in additional volatility in the income statement, with the loss of mark to market via equity for these investments. Additionally, changes in the allowable method for determining the fair value of financial instruments in the financial statement footnotes (“exit price” only) will likely require changes to current methodologies of determining these values, and how they are disclosed in the financial statement footnotes. The new standard applies to public business entities in fiscal years beginning after December 15, 2017, including interim periods within those fiscal years, with early adoption permitted. The adoption of this amendment is not expected to have a significant effect on the Company’s consolidated financial statements. In February 2016, the FASB issued Accounting Standards Update No. 2016-02, Leases (Topic 842) . The guidance in this update is meant to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. The core principle of Topic 842 is that a lessee should recognize the assets and liabilities that arise from leases. All leases create an asset and a liability for the lessee in accordance with FASB Concepts Statement No. 6, Elements of Financial Statements , and, therefore, recognition of those lease assets and lease liabilities represents an improvement over previous GAAP, which did not re

Business Combination (Notes)

Business Combination (Notes)	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	Business Combination On May 1, 2015, the Company acquired all of the equity interests of Central, a bank holding company and the parent company of Central Bank, a commercial bank headquartered in Golden Valley, Minnesota, through the merger of Central with and into the Company. Among other things, this transaction provided the Company with the opportunity to expand the business into new markets and grow the size of the business. At the effective time of the merger, each share of common stock of Central converted into a pro rata portion of (1) 2,723,083 shares of common stock of the Company, and (2) $64.0 million in cash. This business combination was accounted for under the acquisition method of accounting. Accordingly, the results of operations of the acquired company have been included in the Company’s results of operations since the date of acquisition. Under this method of accounting, assets and liabilities acquired are recorded at their estimated fair values. The excess cost over fair value of net assets acquired is recorded as goodwill. As the consideration paid for Central exceeded the net assets acquired, provisional goodwill of $64.7 million has been recorded on the acquisition. Goodwill recorded in this transaction, which reflects the entry into the geographically new markets served by Central. Goodwill recorded in the transaction is not tax deductible. The amounts recognized for the business combination in the financial statements have been determined to be final as of March 31, 2016. Estimated fair values of assets acquired and liabilities assumed in the Central transaction, as of the closing date of the transaction, were as follows: (in thousands) May 1, 2015 ASSETS Cash and due from banks $ 28,404 Investment securities 160,775 Loans 916,973 Premises and equipment 27,908 Goodwill 64,654 Core deposit intangible 12,773 Trade name intangible 1,380 FDIC indemnification asset 3,753 Other real estate owned 8,420 Other assets 14,482 Total assets 1,239,522 LIABILITIES Deposits 1,049,167 Short-term borrowings 16,124 Junior subordinated notes issued to capital trusts 8,050 Subordinated notes payable 12,669 Accrued expenses and other liabilities 11,617 Total liabilities 1,097,627 Net assets 141,895 Consideration: Market value of common stock at $29.31 per share at May 1, 2015 (2,723,083 shares of common stock issued), net of stock illiquidity discount due to restrictions 77,895 Cash paid 64,000 Total fair value of consideration $ 141,895 Purchased loans acquired in a business combination are recorded and initially measured at their estimated fair value as of the acquisition date. Credit discounts are included in the determination of fair value. An allowance for loan losses is not carried over. These purchased loans are segregated into two types: purchased credit impaired loans and purchased non-credit impaired loans without evidence of significant credit deterioration. • Purchased credit impaired loans are accounted for in accordance with ASC 310-30 “Loans and Debt Securities Acquired with Deteriorated Credit Quality” as they display significant credit deterioration since origination and it is probable, as of the acquisition date, that the Company will be unable to collect all contractually required payments from the borrower. • Purchased non-credit impaired loans are accounted for in accordance with ASC 310-20 “ Nonrefundable Fees and Other Costs ” as these loans do not have evidence of significant credit deterioration since origination and it is probable all contractually required payments will be received from the borrower. For purchased non-credit impaired loans, the difference between the estimated fair value of the loans (computed on a loan-by-loan basis) and the principal outstanding is accreted over the remaining life of the loans. For purchased credit impaired loans the difference between contractually required payments at acquisition and the cash flows expected to be collected is referred to as the non-accretable difference. Further, any excess of cash flows expected at acquisition over the estimated fair value is referred to as the accretable yield and is recognized into interest income over the expected remaining life of the loan if the timing and amount of the future cash flows are reasonably estimable. Subsequent to the purchase date, increases in cash flows over those expected at the purchase date are recognized as interest income prospectively. The present value of any decreases in expected cash flows after the purchase date is recognized by recording an allowance for credit losses and a provision for loan losses. The following table presents the purchased loans as of the acquisition date: (in thousands) Purchased Credit Impaired Loans Purchased Non-Credit Impaired Loans Contractually required principal payments $ 36,886 $ 905,314 Nonaccretable difference (6,675 ) — Principal cash flows expected to be collected 30,211 905,314 Accretable discount (1) (1,882 ) (16,670 ) Fair value of acquired loans $ 28,329 $ 888,644 (1) Included in the accretable discount for Purchased Non-Credit Impaired Loans is approximately $10.4 million of estimated undiscounted principal losses. Disclosures required by ASC 805-20-50-1(a) concerning the FDIC indemnification assets have not been included due to the immateriality of the amount involved. See Note 4. “Loans Receivable and the Allowance for Loan Losses” to our consolidated financial statements for additional information related to the FDIC indemnification asset. ASC 805-30-30-7 requires that the consideration transfered in a business combination should be measured at fair value. Since the common shares issued as part of the consideration of the merger included a restriction on their sale, pledge or other disposition, an illiquidity discount has been assigned to the shares based upon the volatility of the underlying shares’ daily returns and the period of restriction. The Company recorded $4.6 million in pre-tax merger-related expenses for the year ended December 31, 2016 , including retention and severance compensation costs in the amount of $2.1 million , which are included in salaries and employee benefits in the consolidated statements of operations. The remainder of merger-related expenses consisted of data processing contract termination expenses in the amount of $1.9 million , which are included in data processing expense in the consolidated statement of operations, professional and legal fees of $0.3 million to directly consummate the merger, included in professional fees in the Company’s consolidated statements of operations and $0.3 million of miscellaneous costs, which are included in other operating expenses. The above expenses include those associated with the merger of Central Bank with and into MidWest One Bank, which was effective on April 2, 2016. During the year ended December 31, 2015 , the Company recorded $3.5 million in pre-tax merger-related expenses. These expenses primarily consisted of $1.9 million of professional and legal fees to directly consummate the merger, included in professional fees in the Company’s consolidated statements of operations, $0.6 million of retention and severance compensation costs which are included in salaries and employee benefits in the consolidated statements of operations, and $1.0 million of service contract termination and miscellaneous costs, which are included in other operating expenses. During the measurement period, specifically the three months ended March 31, 2016, the Company recognized adjustments to the provisional amounts reported at December 31, 2015, which reflect new information that existed as of May 1, 2015 that, if known, would have affected the measurement of the amounts recognized as of that date. In its interim financial statements for the quarter ended March 31, 2016, the Company adjusted the provisional amounts for deferred taxes. The results of this adjustment is reflected in the $0.1 million increase to goodwill during the quarter ended March 31, 2016. The provisional adjustments had no impact on earnings, and in accordance with ASU 2015-16 were recorded during the three months ending March 31, 2016. The following table provides the unaudited pro forma information for the results of operations for the year ended December 31, 2015, as if the acquisition had occurred January 1, 2015. The pro forma results combine the historical results of Central into the Company’s consolidated statement of income including the impact of certain purchase accounting adjustments, including loan discount accretion, investment securities discount accretion, intangible assets amortization, deposit premium accretion and borrowing discount amortization. The pro forma results have been prepared for comparative purposes only and are not necessarily indicative of the results that would have been obtained had the acquisition actually occurred on January 1, 2015. No assumptions have been applied to the pro forma results of operations regarding possible revenue enhancements, expense efficiencies or asset dispositions. Net income in the table below includes merger expenses. Year Ended December 31, (in thousands) 2015 Total revenues (net interest income plus noninterest income) $ 128,613 Net income $ 25,799 The pro forma information above excludes the impact of any provision recorded related to renewing Central loans. Revenues and earnings of the acquired company for the current period have not been disclosed as it is not practicable because Central Bank was merged into MidWest One Bank on April 1, 2016, and separate financial information is not readily available.

Investment Securities (Notes)

Investment Securities (Notes)	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]	Investment Securities The amortized cost and fair value of investment securities available for sale, with gross unrealized gains and losses, are as follows: Gross Gross Amortized Unrealized Unrealized Estimated Cost Gains Losses Fair Value (in thousands) December 31, 2016 U.S. Government agencies and corporations $ 5,895 $ 10 $ — $ 5,905 State and political subdivisions 162,145 3,545 418 165,272 Mortgage-backed securities 61,606 315 567 61,354 Collateralized mortgage obligations 175,506 148 4,387 171,267 Corporate debt securities 72,979 76 602 72,453 Total debt securities 478,131 4,094 5,974 476,251 Other equity securities 1,259 66 58 1,267 Total investment securities $ 479,390 $ 4,160 $ 6,032 $ 477,518 December 31, 2015 U.S. Treasury securities $ 6,931 $ — $ 21 $ 6,910 U.S. Government agencies and corporations 26,600 99 46 26,653 State and political subdivisions 176,794 6,662 72 183,384 Mortgage-backed securities 56,950 569 457 57,062 Collateralized mortgage obligations 107,613 321 1,530 106,404 Corporate debt securities 45,602 50 86 45,566 Total debt securities 420,490 7,701 2,212 425,979 Other equity securities 1,250 50 38 1,262 Total investment securities $ 421,740 $ 7,751 $ 2,250 $ 427,241 The amortized cost and fair value of investment securities held to maturity, with gross unrealized gains and losses, are as follows: Gross Gross Amortized Unrealized Unrealized Estimated Cost Gains Losses Fair Value (in thousands) December 31, 2016 State and political subdivisions $ 107,941 $ 156 $ 2,713 $ 105,384 Mortgage-backed securities 2,398 5 34 2,369 Collateralized mortgage obligations 26,036 — 598 25,438 Corporate debt securities 32,017 149 565 31,601 Total $ 168,392 $ 310 $ 3,910 $ 164,792 December 31, 2015 State and political subdivisions $ 66,454 $ 928 $ 110 $ 67,272 Mortgage-backed securities 3,920 4 38 3,886 Collateralized mortgage obligations 30,505 1 459 30,047 Corporate debt securities 17,544 — 515 17,029 Total $ 118,423 $ 933 $ 1,122 $ 118,234 Investment securities with a carrying value of $212.1 million and $321.6 million at December 31, 2016 and 2015 , respectively, were pledged on public deposits, securities sold under agreements to repurchase and for other purposes, as required or permitted by law. The summary of investment securities shows that some of the securities in the available for sale and held to maturity investment portfolios had unrealized losses, or were temporarily impaired, as of December 31, 2016 and December 31, 2015 . This temporary impairment represents the estimated amount of loss that would be realized if the securities were sold on the valuation date. The following tables present information pertaining to securities with gross unrealized losses as of December 31, 2016 and 2015 , aggregated by investment category and length of time that individual securities have been in a continuous loss position: As of December 31, 2016 Number of Securities Less than 12 Months 12 Months or More Total Available for Sale Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands, except number of securities) State and political subdivisions 63 $ 24,574 $ 389 $ 427 $ 29 $ 25,001 $ 418 Mortgage-backed securities 20 40,752 566 23 1 40,775 567 Collateralized mortgage obligations 29 140,698 3,544 16,776 843 157,474 4,387 Corporate debt securities 11 54,891 602 — — 54,891 602 Other equity securities 1 — — 942 58 942 58 Total 124 $ 260,915 $ 5,101 $ 18,168 $ 931 $ 279,083 $ 6,032 As of December 31, 2015 Number of Securities Less than 12 Months 12 Months or More Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands, except number of securities) U.S. Treasury securities 1 $ 6,910 $ 21 $ — $ — $ 6,910 $ 21 U.S. Government agencies and corporations 1 4,890 46 — — 4,890 46 State and political subdivisions 22 8,419 24 3,177 48 11,596 72 Mortgage-backed securities 27 37,753 457 — — 37,753 457 Collateralized mortgage obligations 23 56,447 420 31,253 1,110 87,700 1,530 Corporate debt securities 8 30,496 86 — — 30,496 86 Other equity securities 1 — — 962 38 962 38 Total 83 $ 144,915 $ 1,054 $ 35,392 $ 1,196 $ 180,307 $ 2,250 As of December 31, 2016 Number of Securities Less than 12 Months 12 Months or More Total Held to Maturity Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands, except number of securities) State and political subdivisions 180 $ 65,174 $ 2,713 $ — $ — $ 65,174 $ 2,713 Mortgage-backed securities 5 2,246 34 — — 2,246 34 Collateralized mortgage obligations 7 18,964 369 6,435 229 25,399 598 Corporate debt securities 11 19,198 187 2,512 378 21,710 565 Total 203 $ 105,582 $ 3,303 $ 8,947 $ 607 $ 114,529 $ 3,910 As of December 31, 2015 Number of Securities Less than 12 Months 12 Months or More Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands, except number of securities) State and political subdivisions 32 $ 9,345 $ 93 $ 2,040 $ 17 $ 11,385 $ 110 Mortgage-backed securities 5 3,723 38 — — 3,723 38 Collateralized mortgage obligations 7 22,571 320 7,416 139 29,987 459 Corporate debt securities 6 15,606 309 680 206 16,286 515 Total 50 $ 51,245 $ 760 $ 10,136 $ 362 $ 61,381 $ 1,122 The Company's assessment of OTTI is based on its reasonable judgment of the specific facts and circumstances impacting each individual security at the time such assessments are made. The Company reviews and considers factual information, including expected cash flows, the structure of the security, the creditworthiness of the issuer, the type of underlying assets and the current and anticipated market conditions. At December 31, 2016 and 2015 , the Company’s mortgage-backed securities and collateralized mortgage obligations portfolios consisted of securities predominantly backed by one- to four-family mortgage loans and underwritten to the standards of and guaranteed by the following government-sponsored agencies: the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and the Government National Mortgage Association. The receipt of principal, at par, and interest on mortgage-backed securities is guaranteed by the respective government-sponsored agency guarantor, such that the Company believes that its mortgage-backed securities and collateralized mortgage obligations do not expose the Company to credit-related losses and that these securities had no OTTI. At December 31, 2016 , approximately 58% of the municipal obligations held by the Company were Iowa-based, and approximately 21% were Minnesota-based. The Company does not intend to sell these municipal obligations, and it is more likely than not that the Company will not be required to sell them until the recovery of their cost. Due to the issuers’ continued satisfaction of their obligations under the securities in accordance with their contractual terms and the expectation that they will continue to do so, management’s intent and ability to hold these securities for a period of time sufficient to allow for any anticipated recovery in fair value, as well as the evaluation of the fundamentals of the issuers’ financial conditions and other objective evidence, the Company believes that the municipal obligations identified in the tables above were temporarily impaired as of December 31, 2016 and 2015 . At December 31, 2016 and 2015 , all but one of the Company’s corporate bonds held an investment grade rating from Moody’s, S&P or Kroll, or carried a guarantee from an agency of the US government. We have evaluated financial statements of the company issuing the non-investment grade bond and found the company’s earnings and equity position to be satisfactory and in line with industry norms. Therefore, we believe the low market value of this investment is temporary and expect to receive all contractual payments. The internal evaluation of the non-investment grade bond along with the investment grade ratings on the remainder of the corporate portfolio lead us to conclude that all of the corporate bonds in our portfolio will continue to pay according to their contractual terms. Since the Company has the ability and intent to hold securities until price recovery, we believe that there is no other-than-temporary-impairment of in the corporate bond portfolio. As of December 31, 2016 , the Company owned $0.3 million of equity securities in banks and financial service-related companies, and $0.9 million of mutual funds invested in debt securities and other debt instruments that will cause units of the fund to be deemed to be qualified under the Community Reinvestment Act. Equity securities are considered to have OTTI whenever they have been in a loss position, compared to current book value, for twelve consecutive months, and the Company does not expect them to recover to their original cost basis. For the years ended December 31, 2016 and 2015 , no impairment charges were recorded, as the affected equity securities were not deemed impaired due to stabilized market prices in relation to the Company’s original purchase price. It is reasonably possible that the fair values of the Company’s investment securities could decline in the future if interest rates increase or the overall economy or the financial conditions of the issuers deteriorate. As a result, there is a risk that OTTI may be recognized in the future, and any such amounts could be material to the Company’s consolidated statements of operations. The contractual maturity distribution of investment debt securities at December 31, 2016 , is summarized as follows: Available For Sale Held to Maturity Amortized Cost Fair Value Amortized Cost Fair Value (in thousands) Due in one year or less $ 11,422 $ 11,468 $ 2,385 $ 2,384 Due after one year through five years 122,263 123,237 9,780 9,700 Due after five years through ten years 95,598 97,246 72,063 71,314 Due after ten years 11,736 11,679 55,730 53,587 Debt securities without a single maturity date 237,112 232,621 28,434 27,807 Total $ 478,131 $ 476,251 $ 168,392 $ 164,792 Mortgage-backed securities and collateralized mortgage obligations are collateralized by mortgage loans and guaranteed by U.S. government agencies. Our experience has indicated that principal payments will be collected sooner than scheduled because of prepayments. Therefore, these securities are not scheduled in the maturity categories indicated above. Equity securities available for sale with an amortized cost of $1.3 million and a fair value of $1.3 million are also excluded from this table. Proceeds from the sales of investment securities available for sale during 2016 were $23.4 million . During 2015 there were $116.8 million sales of investment securities available for sale, while in 2014 there were $33.5 million sales of investment securities available for sale. Realized gains and losses on sales are determined on the basis of specific identification of investments based on the trade date. Realized gains (losses) on investments, including impairment losses for the years ended December 31, 2016 , 2015 and 2014 , were as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Available for sale fixed maturity securities: Gross realized gains $ 469 $ 1,265 $ 1,463 Gross realized losses (5 ) (442 ) (236 ) 464 823 1,227 Equity securities: Gross realized gains — 188 — Gross realized losses — — — — 188 — Total net realized gains and losses $ 464 $ 1,011 $ 1,227

Loans Receivable and the Allowa

Loans Receivable and the Allowance for Loan Losses (Notes)	12 Months Ended
	Dec. 31, 2016
Loans and Leases Receivable Disclosure [Abstract]
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]	Loans Receivable and the Allowance for Loan Losses The composition of allowance for loan losses and loans by portfolio segment and based on impairment method are as follows: Allowance for Loan Losses and Recorded Investment in Loan Receivables As of December 31, 2016 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Total Allowance for loan losses: Individually evaluated for impairment $ 62 $ 2,066 $ 1,924 $ 299 $ — $ 4,351 Collectively evaluated for impairment 1,941 4,199 7,692 2,791 255 16,878 Purchased credit impaired loans — 9 244 368 — 621 Total $ 2,003 $ 6,274 $ 9,860 $ 3,458 $ 255 $ 21,850 Loans receivable Individually evaluated for impairment $ 5,339 $ 11,434 $ 11,450 $ 3,955 $ — $ 32,178 Collectively evaluated for impairment 108,004 449,380 1,036,049 480,143 36,591 2,110,167 Purchased credit impaired loans — 156 16,744 5,898 — 22,798 Total $ 113,343 $ 460,970 $ 1,064,243 $ 489,996 $ 36,591 $ 2,165,143 As of December 31, 2015 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Unallocated Total Allowance for loan losses: Individually evaluated for impairment $ 51 $ 489 $ 2,786 $ 387 $ 1 $ — $ 3,714 Collectively evaluated for impairment 1,366 4,962 5,718 3,539 408 (374 ) 15,619 Purchased credit impaired loans — — 52 42 — — 94 Total $ 1,417 $ 5,451 $ 8,556 $ 3,968 $ 409 $ (374 ) $ 19,427 Loans receivable Individually evaluated for impairment $ 3,072 $ 7,718 $ 23,697 $ 5,725 $ 26 $ — $ 40,238 Collectively evaluated for impairment 118,642 461,275 950,207 517,482 38,506 — 2,086,112 Purchased credit impaired loans — 256 18,037 7,299 — — 25,592 Total $ 121,714 $ 469,249 $ 991,941 $ 530,506 $ 38,532 $ — $ 2,151,942 Included above are loans with a contractual balance of $74.9 million and a recorded balance of $72.4 million at December 31, 2016 , and with a contractual balance of $108.7 million and a recorded balance of $103.0 million at December 31, 2015 , which are covered under loss sharing agreements with the FDIC. The agreements cover certain losses and expenses and expire at various dates through October 7, 2021 . The related FDIC indemnification asset is reported separately in Note 7. “Other Assets.” As of December 31, 2016 , the purchased credit impaired loans included above were $26.2 million , net of a discount of $3.4 million . As of December 31, 2015 the purchased credit impaired loans included above were $33.0 million net of a discount of $7.4 million . Loans with unpaid principal in the amount of $498.3 million and $558.8 million at December 31, 2016 and December 31, 2015 , respectively, were pledged to the FHLB as collateral for borrowings. The changes in the allowance for loan losses by portfolio segment are as follows: Allowance for Loan Loss Activity For the Years Ended December 31, 2016, 2015, and 2014 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Unallocated Total 2016 Beginning balance $ 1,417 $ 5,451 $ 8,556 $ 3,968 $ 409 $ (374 ) $ 19,427 Charge-offs (1,204 ) (3,066 ) (931 ) (782 ) (98 ) — (6,081 ) Recoveries 33 124 192 157 15 — 521 Provision 1,757 3,765 2,043 115 (71 ) 374 7,983 Ending balance $ 2,003 $ 6,274 $ 9,860 $ 3,458 $ 255 $ — $ 21,850 2015 Beginning balance $ 1,506 $ 5,780 $ 4,399 $ 3,167 $ 323 $ 1,188 $ 16,363 Charge-offs (245 ) (692 ) (853 ) (740 ) (92 ) — (2,622 ) Recoveries 1 372 7 143 31 — 554 Provision 155 (9 ) 5,003 1,398 147 (1,562 ) 5,132 Ending balance $ 1,417 $ 5,451 $ 8,556 $ 3,968 $ 409 $ (374 ) $ 19,427 2014 Beginning balance $ 1,358 $ 4,980 $ 5,294 $ 3,185 $ 275 $ 1,087 $ 16,179 Charge-offs (26 ) (685 ) (165 ) (409 ) (76 ) — (1,361 ) Recoveries 10 217 61 22 35 — 345 Provision 164 1,268 (791 ) 369 89 101 1,200 Ending balance $ 1,506 $ 5,780 $ 4,399 $ 3,167 $ 323 $ 1,188 $ 16,363 Loan Portfolio Segment Risk Characteristics Agricultural - Agricultural loans, most of which are secured by crops, livestock, and machinery, are provided to finance capital improvements and farm operations as well as acquisitions of livestock and machinery. The ability of the borrower to repay may be affected by many factors outside of the borrower’s control including adverse weather conditions, loss of livestock due to disease or other factors, declines in market prices for agricultural products and the impact of government regulations. The ultimate repayment of agricultural loans is dependent upon the profitable operation or management of the agricultural entity. Collateral for these loans generally includes accounts receivable, inventory, equipment and real estate. However, depending on the overall financial condition of the borrower, some loans are made on an unsecured basis. The collateral securing these loans may depreciate over time, may be difficult to appraise and may fluctuate in value based on the success of the business. Commercial and Industrial - Commercial and industrial loans are primarily made based on the reported cash flow of the borrower and secondarily on the underlying collateral provided by the borrower. The collateral support provided by the borrower for most of these loans and the probability of repayment are based on the liquidation of the pledged collateral and enforcement of a personal guarantee, if any exists. The primary repayment risks of commercial and industrial loans are that the cash flows of the borrower may be unpredictable, and the collateral securing these loans may fluctuate in value. The size of the loans the Company can offer to commercial customers is less than the size of the loans that competitors with larger lending limits can offer. This may limit the Company’s ability to establish relationships with the largest businesses in the areas in which the Company operates. As a result, the Company may assume greater lending risks than financial institutions that have a lesser concentration of such loans and tend to make loans to larger businesses. Collateral for these loans generally includes accounts receivable, inventory, equipment and real estate. However, depending on the overall financial condition of the borrower, some loans are made on an unsecured basis. The collateral securing these loans may depreciate over time, may be difficult to appraise and may fluctuate in value based on the success of the business. In addition, a decline in the U.S. economy could harm or continue to harm the businesses of the Company’s commercial and industrial customers and reduce the value of the collateral securing these loans. Commercial Real Estate - The Company offers mortgage loans to commercial and agricultural customers for the acquisition of real estate used in their businesses, such as offices, warehouses and production facilities, and to real estate investors for the acquisition of apartment buildings, retail centers, office buildings and other commercial buildings. The market value of real estate securing commercial real estate loans can fluctuate significantly in a short period of time as a result of market conditions in the geographic area in which the real estate is located. Adverse developments affecting real estate values in one or more of the Company’s markets could increase the credit risk associated with its loan portfolio. Additionally, real estate lending typically involves higher loan principal amounts than other loans, and the repayment of the loans generally is dependent, in large part, on sufficient income from the properties securing the loans to cover operating expenses and debt service. Economic events or governmental regulations outside of the Company’s control or that of the borrower could negatively impact the future cash flow and market values of the affected properties. Residential Real Estate - The Company generally retains short-term residential mortgage loans that are originated for its own portfolio but sells most long-term loans to other parties while retaining servicing rights on the majority of those loans. The market value of real estate securing residential real estate loans can fluctuate as a result of market conditions in the geographic area in which the real estate is located. Adverse developments affecting real estate values in one or more of the Company’s markets could increase the credit risk associated with its loan portfolio. Additionally, real estate lending typically involves higher loan principal amounts than other loans, and the repayment of the loans generally is dependent, in large part, on the borrower’s continuing financial stability, and is therefore more likely to be affected by adverse personal circumstances. Consumer - Consumer loans typically have shorter terms, lower balances, higher yields and higher risks of default than real estate-related loans. Consumer loan collections are dependent on the borrower’s continuing financial stability, and are therefore more likely to be affected by adverse personal circumstances. Collateral for these loans generally includes automobiles, boats, recreational vehicles, mobile homes, and real estate. However, depending on the overall financial condition of the borrower, some loans are made on an unsecured basis. The collateral securing these loans may depreciate over time, may be difficult to recover and may fluctuate in value based on condition. In addition, a decline in the United States economy could result in reduced employment, impacting the ability of customers to repay their obligations. Purchased Loans Policy All purchased loans (nonimpaired and impaired) are initially measured at fair value as of the acquisition date in accordance with applicable authoritative accounting guidance. Credit discounts are included in the determination of fair value. An allowance for loan losses is not recorded at the acquisition date for loans purchased. Individual loans acquired through the completion of a transfer, including loans that have evidence of deterioration of credit quality since origination and for which it is probable, at acquisition, that the Company will be unable to collect all contractually required payments receivable, are referred to herein as “purchased credit impaired loans.” In determining the acquisition date fair value and estimated credit losses of purchased credit impaired loans, and in subsequent accounting, the Company accounts for loans individually. Contractually required payments for interest and principal that exceed the undiscounted cash flows expected at acquisition, or the “nonaccretable difference,” are not recognized as a yield adjustment or as a loss accrual or valuation allowance. Expected cash flows at the purchase date in excess of the fair value of loans, if any, are recorded as interest income over the expected life of the loans if the timing and amount of future cash flows are reasonably estimable. Subsequent to the purchase date, increases in cash flows over those expected at the purchase date are recognized as interest income prospectively. The present value of any decreases in expected cash flows after the purchase date is recognized by recording an allowance for loan losses and a provision for loan losses. If the Company does not have the information necessary to reasonably estimate cash flows to be expected, it may use the cost-recovery method or cash-basis method of income recognition. Charge-off Policy The Company requires a loan to be charged-off, in whole or in part, as soon as it becomes apparent that some loss will be incurred, or when its collectability is sufficiently questionable that it no longer is considered a bankable asset. The primary considerations when determining if and how much of a loan should be charged-off are as follows: (1) the potential for future cash flows; (2) the value of any collateral; and (3) the strength of any co-makers or guarantors. When it is determined that a loan requires a partial or full charge-off, a request for approval of a charge-off is submitted to the Company's President, Executive Vice President and Chief Credit Officer, and the Senior Regional Loan Officer. The Bank's board of directors formally approves all loan charge-offs. Once a loan is charged-off, it cannot be restructured and returned to the Company's books. The Allowance for Loan and Lease Losses The Company requires the maintenance of an adequate ALLL in order to cover estimated probable losses without eroding the Company’s capital base. Calculations are done at each quarter end, or more frequently if warranted, to analyze the collectability of loans and to ensure the adequacy of the allowance. In line with FDIC directives, the ALLL calculation does not include consideration of loans held for sale or off-balance-sheet credit exposures (such as unfunded letters of credit). Determining the appropriate level for the ALLL relies on the informed judgment of management, and as such, is subject to inexactness. Given the inherently imprecise nature of calculating the necessary ALLL, the Company’s policy permits the actual ALLL to be between 20% above and 5% below the “indicated reserve.” As part of the merger between MidWest One Bank and Central Bank, management developed a single methodology for determining the amount of the ALLL that would be needed at the combined bank. The new methodology is a hybrid of the methods used at MidWest One Bank and Central Bank prior to the bank merger. The refined allowance calculation allocates the portion of allowance that was previously deemed to be unallocated to instead be included in management’s determination of appropriate qualitative factors. These qualitative factors include (i) national and local economic conditions, (ii) the quality and experience of lending staff and management, (iii) changes in lending policies and procedures, (iv) changes in volume and severity of past due loans, classified loans and non-performing loans, (v) potential impact of any concentrations of credit, (vi) changes in the nature and terms of loans such as growth rates and utilization rates, (vii) changes in the value of underlying collateral for collateral-dependent loans, considering the Company’s disposition bias, and (viii) the effect of other external factors such as the legal and regulatory environment. The Company may also consider other qualitative factors for additional allowance allocations, including changes in the Company’s loan review process. Changes in the criteria used in this evaluation or the availability of new information could cause the allowance to be increased or decreased in future periods. In addition, bank regulatory agencies, as part of their examination process, may require adjustments to the allowance for loan losses based on their judgments and estimates. Loans Reviewed Individually for Impairment The Company identifies loans to be reviewed and evaluated individually for impairment based on current information and events and the probability that the borrower will be unable to repay all amounts due according to the contractual terms of the loan agreement. Specific areas of consideration include: size of credit exposure, risk rating, delinquency, nonaccrual status, and loan classification. The level of individual impairment is measured using one of the following methods: (1) the fair value of the collateral less costs to sell; (2) the present value of expected future cash flows, discounted at the loan's effective interest rate; or (3) the loan's observable market price. Loans that are deemed fully collateralized or have been charged down to a level corresponding with any of the three measurements require no assignment of reserves from the ALLL. A loan modification is a change in an existing loan contract that has been agreed to by the borrower and the Bank, which may or may not be a troubled debt restructure or “TDR.” All loans deemed TDR are considered impaired. A loan is considered a TDR when, for economic or legal reasons related to a borrower’s financial difficulties, a concession is granted to the borrower that would not otherwise be considered. Both financial distress on the part of the borrower and the Bank’s granting of a concession, which are detailed further below, must be present in order for the loan to be considered a TDR. All of the following factors are indicators that the debtor is experiencing financial difficulties (one or more items may be present): • The debtor is currently in default on any of its debt. • The debtor has declared or is in the process of declaring bankruptcy. • There is significant doubt as to whether the debtor will continue to be a going concern. • Currently, the debtor has securities being held as collateral that have been delisted, are in the process of being delisted, or are under threat of being delisted from an exchange. • Based on estimates and projections that only encompass the current business capabilities, the debtor forecasts that its entity-specific cash flows will be insufficient to service the debt (both interest and principal) in accordance with the contractual terms of the existing agreement through maturity. • Absent the current modification, the debtor cannot obtain funds from sources other than the existing creditors at an effective interest rate equal to the current market interest rate for similar debt for a non-troubled debtor. The following factors are potential indicators that a concession has been granted (one or multiple items may be present): • The borrower receives a reduction of the stated interest rate for the remaining original life of the debt. • The borrower receives an extension of the maturity date or dates at a stated interest rate lower that the current market interest rate for new debt with similar risk characteristics. • The borrower receives a reduction of the face amount or maturity amount of the debt as stated in the instrument or other agreement. • The borrower receives a deferral of required payments (principal and/or interest). • The borrower receives a reduction of the accrued interest. The following table sets forth information on the Company's TDRs by class of financing receivable occurring during the stated periods. TDRs may include multiple concessions, and the disclosure classifications in the table are based on the primary concession provided to the borrower. For the Year Ended December 31, 2016 2015 2014 Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment (dollars in thousands) Troubled Debt Restructurings: Agricultural Extended maturity date 1 25 25 0 — — 0 — — Commercial and industrial Extended maturity date 0 — — 0 — — 1 1,405 1,405 Commercial real estate: Commercial real estate-other Other 1 1,000 700 0 — — 0 — — Residential real estate: One- to four- family first liens Interest rate reduction 2 394 394 1 151 151 1 285 292 One- to four- family junior liens Interest rate reduction 1 71 71 0 — — 0 — — Total 5 $ 1,490 $ 1,190 1 $ 151 $ 151 2 $ 1,690 $ 1,697 Loans by class of financing receivable modified as TDRs within the previous 12 months and for which there was a payment default during the stated periods were: For the Year Ended December 31, 2016 2015 2014 Number of Contracts Recorded Investment Number of Contracts Recorded Investment Number of Contracts Recorded Investment (dollars in thousands) Troubled Debt Restructurings That Subsequently Defaulted: Total 0 $ — 0 $ — 0 $ — Loans Reviewed Collectively for Impairment All loans not evaluated individually for impairment will be separated into homogeneous pools to be collectively evaluated. Loans will be first grouped into the various loan types (i.e. commercial, agricultural, consumer, etc.) and further segmented within each subset by risk classification (i.e. pass, special mention/watch, and substandard). Homogeneous loans past due 60-89 days and 90 days and over are classified special mention/watch and substandard, respectively, for allocation purposes. The Company's historical loss experience for each loan type is calculated using the fiscal quarter-end data for the most recent 20 quarters as a starting point for estimating losses. In addition, other prevailing qualitative or environmental factors likely to cause probable losses to vary from historical data are incorporated in the form of adjustments to increase or decrease the loss rate applied to each group. These adjustments are documented and fully explain how the current information, events, circumstances, and conditions impact the historical loss measurement assumptions. Although not a comprehensive list, the following are considered key factors and are evaluated with each calculation of the ALLL to determine if adjustments to historical loss rates are warranted: • Changes in national and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments. • Changes in the quality and experience of lending staff and management. • Changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses. • Changes in the volume and severity of past due loans, classified loans and non-performing loans. • The existence and potential impact of any concentrations of credit. • Changes in the nature and terms of loans such as growth rates and utilization rates. • Changes in the value of underlying collateral for collateral-dependent loans, considering the Company’s disposition bias. • The effect of other external factors such as the legal and regulatory environment. The items listed above are used to determine the pass percentage for loans evaluated under ASC 450, and as such, are applied to the loans risk rated pass. Due to the inherent risks associated with special mention/watch risk rated loans (i.e. early stages of financial deterioration, technical exceptions, etc.), this subset is reserved at a level that will cover losses above a pass allocation for loans that had a loss in the last 20 quarters in which the loan was risk rated special mention/watch at the time of the loss. Substandard loans carry greater risk than special mention/watch loans, and as such, this subset is reserved at a level that will cover losses above a pass allocation for loans that had a loss in the last 20 quarters in which the loan was risk rated substandard at the time of the loss. Ongoing analysis will be performed to support these factor multiples. The following table sets forth the risk category of loans by class of loans and credit quality indicator based on the most recent analysis performed, as of December 31, 2016 and 2015 : Pass Special Mention/Watch Substandard Doubtful Loss Total (in thousands) 2016 Agricultural $ 95,103 $ 14,089 $ 4,151 $ — $ — $ 113,343 Commercial and industrial 429,392 11,065 19,016 8 — 459,481 Credit cards 1,489 — — — — 1,489 Commercial real estate: Construction & development 121,982 2,732 1,971 — — 126,685 Farmland 83,563 8,986 2,430 — — 94,979 Multifamily 134,975 548 480 — — 136,003 Commercial real estate-other 666,767 20,955 18,854 — — 706,576 Total commercial real estate 1,007,287 33,221 23,735 — — 1,064,243 Residential real estate: One- to four- family first liens 359,029 2,202 11,002 — — 372,233 One- to four- family junior liens 114,233 1,628 1,902 — — 117,763 Total residential real estate 473,262 3,830 12,904 — — 489,996 Consumer 36,419 1 134 37 — 36,591 Total $ 2,042,952 $ 62,206 $ 59,940 $ 45 $ — $ 2,165,143 2015 Agricultural $ 111,361 $ 8,536 $ 1,817 $ — $ — $ 121,714 Commercial and industrial 436,857 12,893 17,652 10 — 467,412 Credit cards 1,354 19 4 — — 1,377 Overdrafts 1,168 100 215 — — 1,483 Commercial real estate: Construction & development 114,640 2,406 3,707 — — 120,753 Farmland 82,442 2,408 4,234 — — 89,084 Multifamily 119,139 371 2,253 — — 121,763 Commercial real estate-other 609,651 19,402 31,288 — — 660,341 Total commercial real estate 925,872 24,587 41,482 — — 991,941 Residential real estate: One- to four- family first liens 410,143 4,813 13,042 235 — 428,233 One- to four- family junior liens 96,223 1,782 4,209 59 — 102,273 Total residential real estate 506,366 6,595 17,251 294 — 530,506 Consumer 37,184 6 278 41 — 37,509 Total $ 2,020,162 $ 52,736 $ 78,699 $ 345 $ — $ 2,151,942 Included within the special mention, substandard, and doubtful categories at December 31, 2016 and 2015 were purchased credit impaired loans totaling $15.3 million and $23.7 million , respectively. Special Mention/Watch - A special mention/watch asset has potential weaknesses that deserve management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects for the asset or in the Company’s credit position at some future date. Special mention/watch assets are not adversely classified and do not expose the Company to sufficient risk to warrant adverse classification. Substandard - Substandard loans are inadequately protected by the current net worth and paying capacity of the obligor or of the collateral pledged, if any. Loans so classified 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. Doubtful - Loans classified as doubtful have all the weaknesses inherent in those classified as substandard with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently known facts, conditions and values, highly questionable and improbable. Loss - Loans classified as loss are considered uncollectible and of such little value that their continuance as bankable assets is not warranted. This classification does not mean that the loan has absolutely no recovery or salvage value but rather it is not practical or desirable to defer writing off this basically worthless asset even though partial recovery may be effected in the future. The following table presents loans individually evaluated for impairment, excluding purchased credit impaired loans, by class of loan, as of December 31, 2016 and 2015 : As of December 31, 2016 2015 Recorded Investment Unpaid Principal Balance Related Allowance Recorded Investment Unpaid Principal Balance Related Allowance (in thousands) With no related allowance recorded: Agricultural $ 3,673 $ 4,952 $ — $ 1,512 $ 2,084 $ — Commercial and industrial 6,211 6,259 — 6,487 6,752 — Credit cards — — — — — — Commercial real estate: Construction & development 445 1,170 — 321 448 — Farmland 2,230 2,380 — 2,711 2,870 — Multifamily — — — 1,632 1,798 — Commercial real estate-other 2,224 2,384 — 12,230 12,642 — Total commercial real estate 4,899 5,934 — 16,894 17,758 — Residential real estate: One- to four- family first liens 2,429 2,442 — 2,494 2,533 — One- to four- family junior liens — — — 1,297 1,308 — Total residential real estate 2,429 2,442 — 3,791 3,841 — Consumer — — — 17 33 — Total $ 17,212 $ 19,587 $ — $ 28,701 $ 30,468 $ — With an allowance recorded: Agricultural $ 1,666 $ 1,669 $ 62 $ 1,560 $ 1,560 $ 51 Commercial and industrial 5,223 5,223 2,066 1,231 1,258 489 Credit cards — — — — — — Commercial real estate: Construction & development 263 270 21 34 34 34 Farmland — — — 69 69 3 Multifamily — — — 224 224 73 Commercial real estate-other 6,288 6,344 1,903 6,476 6,478 2,676 Total commercial real estate 6,551 6,614 1,924 6,803 6,805 2,786 Residential real estate: One- to four- family first liens 1,526 1,526 299 1,919 2,056 383 One- to four- family junior liens — — — 15 15 4 Total residential real estate 1,526 1,526 299 1,934 2,071 387 Consumer — — — 9 9 1 Total $ 14,966 $ 15,032 $ 4,351 $ 11,537 $ 11,703 $ 3,714 Total: Agricultural $ 5,339 $ 6,621 $ 62 $ 3,072 $ 3,644 $ 51 Commercial and industrial 11,434 11,482 2,066 7,718 8,010 489 Credit cards — — — — — — Commercial real estate: Construction & development 708 1,440 21 355 482 34 Farmland 2,230 2,380 — 2,780 2,939 3 Multifamily — — — 1,856 2,022 73 Commercial real estate-other 8,512 8,728 1,903 18,706 19,120 2,676 Total commercial real estate 11,450 12,548 1,924 23,697 24,563 2,786 Residential real estate: One- to four- family first liens 3,955 3,968 299 4,413 4,589 383 One- to four- family junior liens — — — 1,312 1,323 4 Total residential real estate 3,955 3,968 299 5,725 5,912 387 Consumer — — — 26 42 1 Total $ 32,178 $ 34,619 $ 4,351 $ 40,238 $ 42,171 $ 3,714 The following table presents the average recorded investment and interest income recognized for loans individually evaluated for impairment, excluding purchased credit impaired loans, by class of loan, during the stated periods: For the Year Ended December 31, 2016 2015 2014 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized (in thousands) With no related allowance recorded: Agricultural $ 3,815 $ 88 $ 1,533 $ 58 $ 1,413 $ 211 Commercial and industrial 6,540 79 6,769 424 2,234 160 Credit cards — — — — — — Commercial real estate: Construction & development 390 54 325 7 49 — Farmland 2,389 97 2,743 128 2,288 456 Multifamily — — 1,833 68 — — Commercial real estate-other 2,243 60 12,772 446 975 — Total commercial real estate 5,022 211 17,673 649 3,312 456 Residential real estate: One- to four- family first liens 2,430 101 2,469 81 547 32 One- to four- family junior liens — — 1,313 42 134 6 Total residential real estate 2,430 101 3,782 123 681 38 Consumer — — 21 2 8 — Total $ 17,807 $ 479 $ 29,778 $ 1,256 $ 7,648 $ 865 With an allowance recorded: Agricultural $ 1,678 $ 46 $ 1,572 $ 48 $ 1,627 $ 203 Commercial and industrial 5,277 74 1,313 67 1,044 104 Credit cards — — — — — — Commercial real estate: Construction & development 263 3 34 — 35 3 Farmland — — 70 2 74 3 Multifamily — — 226 6 — — Commercial real estate-other 6,515 — 6,528 344 551 43 Total commercial real estate 6,778 3 6,858 352 660 49 Residential real estate: One- to four- family first liens 1,559 41 1,928 44 2,612 203 One- to four- family junior liens — — 15 — 74 — Total residential real estate 1,559 41 1,943 44 2,686 203 Consumer — — 9 — 31 5 Total $ 15,292 $ 164 $ 11,695 $ 511 $ 6,048 $ 564 Total: Agricultural $ 5,493 $ 134 $ 3,105 $ 106 $ 3,040 $ 414 Commercial and industrial 11,817 153 8,082 491 3,278 264 Credit cards — — — — — — Commercial real estate: Construction & development 653 57 359 7 84 3 Farmland 2,389 97 2,813 130 2,362 459 Multifamily — — 2,059 74 — — Commercial real estate-other 8,758 60 19,300 790 1,526 43 Total commercial real estate 11,800 214 24,531 1,001 3,972 505 Residential real estate: One- to four- family first liens 3,989 142 4,397 125 3,159 235 One- to four- family junior liens — — 1,328 42 208 6 Total residential real estate 3,989 142 5,725 167 3,367 241 Consumer — — 30 2 39 5 Total $ 33,099 $ 643 $ 41,473 $ 1,767 $ 13,696 $ 1,429 The following table presents the contractual aging of the recorded investment in past due loans by class of loans at December 31, 2016 and 2015 : 30 - 59 Days Past Due 60 - 89 Days Past Due 90 Days or More Past Due Total Past Due Current Total Loans Receivable (in thousands) 2016 Agricultural $ 44 $ — $ 399 $ 443 $ 112,900 $ 113,343 Commercial and industrial 2,615 293 9,654 12,562 446,919 459,481 Credit cards — — — — 1,489 1,489 Commercial real estate: Construction & development 630 — 297 927 125,758 126,685 Farmland 373 — 91 464 94,515 94,979 Multifamily — 129 — 129 135,874 136,003 Commercial real estate-other 1,238 763 6,655 8,656 697,920 706,576 Total commercial real estate 2,241 892 7,043 10,176 1,054,067 1,064,243 Residential real estate: One- to four- family first liens 2,851 1,143 1,328 5,322 366,911 372,233 One- to four- family junior liens 437 151 150 738 117,025 117,763 Total residential real estate 3,288 1,294 1,478 6,060 483,936 489,996 Consumer 50 23 33 106 36,485 36,591 Total $ 8,238 $ 2,502 $ 18,607 $ 29,347 $ 2,135,796 $ 2,165,143 Included in the totals above are the following purchased credit impaired loans $ 965 $ 489 $ 549 $ 2,003 $ 20,795 $ 22,798 2015 Agricultural $ 19 $ 190 $ 169 $ 378 $ 121,336 $ 121,714 Commercial and industrial 1,046 710 644 2,400 465,012 467,412 Credit cards 2 17 4 23 1,354 1,377 Overdrafts 175 8 31 214 1,269 1,483 Commercial real estate: Construction & development — — 415 415 120,338 120,753 Farmland 120 — 80 200 88,884 89,084 Multifamily — — 224 224 121,539 121,763

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment Disclosure [Text Block]	Premises and Equipment Premises and equipment as of December 31, 2016 and 2015 were as follows: As of December 31, 2016 2015 (in thousands) Land $ 12,970 $ 13,270 Buildings and leasehold improvements 68,405 60,871 Furniture and equipment 15,851 17,160 Construction in process 1,439 10,972 Premises and equipment 98,665 102,273 Accumulated depreciation and amortization 23,622 26,071 Premises and equipment, net $ 75,043 $ 76,202 Premises and equipment depreciation and amortization expense for the years ended December 31, 2016 , 2015 and 2014 was $4.6 million , $3.3 million and $2.2 million , respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets Disclosure [Text Block]	Goodwill and Intangible Assets The excess of the cost of an acquisition over the fair value of the net assets acquired, including core deposit, trade name, and client relationship intangibles, consists of goodwill. Under ASC Topic 350, goodwill and the non-amortizing portion of the trade name intangible are subject to at least annual assessments for impairment by applying a fair value based test. The Company reviews goodwill and the non-amortizing portion of the trade name intangible at the reporting unit level to determine potential impairment annually on October 1, or more frequently if events or changes in circumstances indicate that the carrying value may not be recoverable, by comparing the carrying value of the reporting unit with the fair value of the reporting unit. No impairment was recorded on either the goodwill or the trade name intangible assets in 2016 , 2015 , or 2014 . The carrying amount of goodwill was $64.7 million at December 31, 2016 and $64.6 million at December 31, 2015 . The increase of $0.1 million in goodwill was due to the finalization of accounting related to the Central merger. In addition to goodwill, the Company recognized a $12.8 million core deposit intangible and a $1.4 million trade name intangible in 2015 due to the Central merger. Amortization of intangible assets is recorded using an accelerated method based on the estimated useful life of insurance agency intangible, the core deposit intangible, the amortizing portion of the trade name intangible, and the customer list intangible. Projections of amortization expense are based on existing asset balances and the remaining useful lives. The following table presents the changes in the carrying amount of intangibles (excluding goodwill), gross carrying amount, accumulated amortization, net book value, and weighted average life as of December 31, 2016 and 2015 : Insurance Agency Intangible Core Deposit Intangible Indefinite-Lived Trade Name Intangible Finite-Lived Trade Name Intangible Customer List Intangible Total (dollars in thousands) December 31, 2016 Balance, beginning of period $ 275 $ 10,480 $ 7,040 $ 1,203 $ 143 $ 19,141 Amortization expense (72 ) (3,634 ) — (243 ) (21 ) (3,970 ) Balance at end of period $ 203 $ 6,846 $ 7,040 $ 960 $ 122 $ 15,171 Gross carrying amount $ 1,320 $ 18,206 $ 7,040 $ 1,380 $ 330 $ 28,276 Accumulated amortization (1,117 ) (11,360 ) — (420 ) (208 ) (13,105 ) Net book value $ 203 $ 6,846 $ 7,040 $ 960 $ 122 $ 15,171 Remaining weighted average useful life (years) 7 5 8 7 Insurance Agency Intangible Core Deposit Intangible Indefinite-Lived Trade Name Intangible Finite-Lived Trade Name Intangible Customer List Intangible Total (dollars in thousands) December 31, 2015 Balance, beginning of period $ 364 $ 691 $ 7,040 $ — $ 164 $ 8,259 Additions from business combination — 12,773 — 1,380 — 14,153 Amortization expense (89 ) (2,984 ) — (177 ) (21 ) (3,271 ) Balance at end of period $ 275 $ 10,480 $ 7,040 $ 1,203 $ 143 $ 19,141 Gross carrying amount $ 1,320 $ 18,206 $ 7,040 $ 1,380 $ 330 $ 28,276 Accumulated amortizations (1,045 ) (7,726 ) — (177 ) (187 ) (9,135 ) Net book value $ 275 $ 10,480 $ 7,040 $ 1,203 $ 143 $ 19,141 Remaining weighted average useful life (years) 7 6 9 8 The following table summarizes future amortization expense of intangible assets: Insurance Core Trade Customer Agency Deposit Name List Intangible Premium Intangible Intangible Totals (in thousands) Year ending December 31, 2017 $ 55 $ 2,835 $ 216 $ 19 $ 3,125 2018 38 2,037 188 18 2,281 2019 21 1,312 161 17 1,511 2020 20 613 133 16 782 2021 19 49 106 15 189 Thereafter 50 — 156 37 243 Total $ 203 $ 6,846 $ 960 $ 122 $ 8,131

Other Assets

Other Assets	12 Months Ended
	Dec. 31, 2016
Other Assets [Abstract]
Other Assets Disclosure [Text Block]	Other Assets The components of the Company’s other assets as of December 31, 2016 and 2015 were as follows: As of December 31, 2016 2015 (in thousands) Federal Home Loan Bank Stock $ 12,800 $ 9,832 FDIC indemnification asset, net 479 4,274 Prepaid expenses 1,760 2,271 Mortgage servicing rights 1,951 2,249 Federal and state taxes, current — 1,079 Accounts receivable & other miscellaneous assets 1,323 2,104 $ 18,313 $ 21,809 The Bank is a member of the FHLB of Des Moines, and ownership of FHLB stock is a requirement for such membership. The amount of FHLB stock the Bank is required to hold is directly related to the amount of FHLB advances borrowed. Because this security is not readily marketable and there are no available market values, this security is carried at cost and evaluated for potential impairment each quarter. No impairment was recorded on FHLB stock in 2016 or 2015 . Redemption of this investment is at the option of the FHLB. As part of the Central merger, the Company became a party to certain loss-share agreements with the FDIC from previous Central-related acquisitions. These agreements cover realized losses on loans and foreclosed real estate for specified periods. These loss-share assets are measured separately from the loan portfolios because they are not contractually embedded in the loans and are not transferable with the loans should the Company choose to dispose of them. Fair values of the loss share assets at the acquisition dates were estimated based on projected cash flows available for loss-share based on the credit adjustments estimated for each loan. Mortgage servicing rights are recorded at fair value based on assumptions provided by a third-party valuation service. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the servicing cost per loan, the discount rate, the escrow float rate, an inflation rate, ancillary income, prepayment speeds and default rates and losses.

Loans Serviced for Others

Loans Serviced for Others	12 Months Ended
	Dec. 31, 2016
Loans Serviced for Others [Abstract]
Loans Serviced For Others [Text Block]	Loans Serviced for Others Loans serviced for others are not included in the accompanying consolidated balance sheets. The unpaid principal balances of mortgage and other loans serviced for others were $391.8 million and $362.3 million at December 31, 2016 and 2015 , 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 fair value adjustments to capitalized mortgage servicing rights.

Time Deposits

Time Deposits	12 Months Ended
	Dec. 31, 2016
Deposits [Abstract]
Deposit Liabilities Disclosures [Text Block]	Time Deposits Time deposits that meet or exceed the FDIC insurance limit of $250,000 at December 31, 2016 and December 31, 2015 were $177.9 million and $162.5 million , respectively. At December 31, 2016 , the scheduled maturities of certificates of deposits were as follows: (in thousands) 2017 $ 402,316 2018 100,028 2019 81,325 2020 27,050 2021 40,410 Thereafter 753 Total $ 651,882 The Company had $2.6 million and $2.8 million in brokered time deposits through the CDARS program as of December 31, 2016 and December 31, 2015 , respectively. The CDARS program coordinates, on a reciprocal basis, a network of banks to spread deposits exceeding the FDIC insurance coverage limits out to numerous institutions in order to provide insurance coverage for all participating deposits.

Short-Term Borrowings

Short-Term Borrowings	12 Months Ended
	Dec. 31, 2016
Short-term Debt [Abstract]
Debt Disclosure [Text Block]	Short-Term Borrowings Short-term borrowings were as follows as of December 31, 2016 and December 31, 2015 : December 31, 2016 December 31, 2015 (dollars in thousands) Weighted Average Cost Balance Weighted Average Cost Balance Federal funds purchased 0.83 35,684 0.34 1,500 Securities sold under agreements to repurchase 0.22 82,187 0.31 67,463 Total 0.40 % $ 117,871 0.31 % $ 68,963 At December 31, 2016 and 2015 , the Company had no borrowings through the Federal Reserve Discount Window, while the borrowing capacity at December 31, 2016 and 2015 was $11.5 million and $11.8 million , respectively. As of December 31, 2016 and December 31, 2015 , the Bank had municipal securities with a market value of $12.8 million and $13.1 million , respectively, pledged to the Federal Reserve to secure potential borrowings. The Company also has various other unsecured federal funds agreements with correspondent banks. As of December 31, 2016 and 2015 there were $35.7 million and $1.5 million of borrowings through these correspondent bank federal funds agreements, respectively. Securities sold under agreements to repurchase are agreements in which the Company acquires funds by selling assets to another party under a simultaneous agreement to repurchase the same assets at a specified price and date. The Company enters into repurchase agreements and also offers a demand deposit account product to customers that sweeps their balances in excess of an agreed upon target amount into overnight repurchase agreements. All securities sold under agreements to repurchase are recorded on the face of the balance sheet. On April 30, 2015 , the Company entered into a $5.0 million unsecured line of credit with a correspondent bank. Interest is payable at a rate of one-month LIBOR + 2.00% . The line is scheduled to mature on April 27, 2017 . The Company had no balance outstanding under this agreement as of December 31, 2016 .

Subordinated Notes Payable (Not

Subordinated Notes Payable (Notes)	12 Months Ended
	Dec. 31, 2016
Junior Subordinated Notes [Abstract]
Subordinated Borrowings Disclosure [Text Block]	Subordinated Notes Payable The Company has established three statutory business trusts under the laws of the state of Delaware: Central Bancshares Capital Trust II, Barron Investment Capital Trust I, and MidWestOne Statutory Trust II. The trusts exist for the exclusive purposes of (i) issuing trust securities representing undivided beneficial interests in the assets of the respective trust; (ii) investing the gross proceeds of the trust securities in junior subordinated deferrable interest debentures (junior subordinated notes); and (iii) engaging in only those activities necessary or incidental thereto. For regulatory capital purposes, these trust securities qualify as a component of Tier 1 capital. The table below summarizes the outstanding junior subordinated notes and the related trust preferred securities issued by each trust as of as of December 31, 2016 and December 31, 2015 : Face Value Book Value Interest Rate Year-end Interest Rate Maturity Date Callable Date (in thousands) 2016 Central Bancshares Capital Trust II (1) (2) $ 7,217 $ 6,614 Three-month LIBOR + 3.50% 4.46 % 03/15/2038 03/15/2013 Barron Investment Capital Trust I (1) (2) 2,062 1,614 Three-month LIBOR + 2.15% 3.15 % 09/23/2036 09/23/2011 MidWestOne Statutory Trust II (1) 15,464 15,464 Three-month LIBOR + 1.59% 2.55 % 12/15/2037 12/15/2012 Total $ 24,743 $ 23,692 2015 Central Bancshares Capital Trust II (1) (2) $ 7,217 $ 6,552 Three-month LIBOR + 3.50% 4.01 % 3/15/2038 3/15/2013 Barron Investment Capital Trust I (1) (2) 2,062 1,571 Three-month LIBOR + 2.15% 2.74 % 9/23/2036 9/23/2011 MidWestOne Statutory Trust II (1) 15,464 15,464 Three-month LIBOR + 1.59% 2.10 % 12/15/2037 12/15/2012 Total $ 24,743 $ 23,587 (1) All distributions are cumulative and paid in cash quarterly. (2) Central Bancshares Capital Trust II was established by Central and Barron Investment Capital Trust I was acquired by Central, prior to the Company’s merger with Central, and the obligations under the junior subordinated notes issued by Central to these trusts were assumed by the Company. The trust preferred securities are subject to mandatory redemption, in whole or in part, upon repayment of the junior subordinated notes at the stated maturity date or upon redemption of the junior subordinated notes. 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 obligation under the junior subordinated notes and other relevant trust agreements, in aggregate, constitutes 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 and, therefore, distributions on the trust preferred securities, for up to five years , but not beyond the stated maturity date in the table above. During any such deferral period the Company may not pay cash dividends on its stock and generally may not repurchase its stock. The Company assumed a subordinated note held by 1907 EJF Fund, LTD, which was issued by Central prior to the Company’s merger on May 1, 2015, with a face value of $12.3 million . On June 23, 2015 the Company redeemed the subordinated note.

Long-Term Borrowings

Long-Term Borrowings	12 Months Ended
	Dec. 31, 2016
Long-term Debt, by Type, Current and Noncurrent [Abstract]
Long-term Debt [Text Block]	Long-Term Borrowings Long-term borrowings were as follows as of December 31, 2016 and December 31, 2015 : December 31, 2016 December 31, 2015 (dollars in thousands) Weighted Average Cost Balance Weighted Average Cost Balance FHLB Borrowings 1.56 % $ 115,000 1.64 % $ 87,000 Note payable to unaffiliated bank 2.52 17,500 2.17 22,500 Total 1.69 % $ 132,500 1.75 % $ 109,500 The Company utilizes FHLB borrowings as a supplement to customer deposits to fund earning assets and to assist in managing interest rate risk. As a member of the Federal Home Loan Bank of Des Moines, the Bank may borrow funds from the FHLB in amounts up to 35% of the Bank’s total assets, provided the Bank is able to pledge an adequate amount of qualified assets to secure the borrowings. Advances from the FHLB are collateralized primarily by one- to four-family residential, commercial and agricultural real estate first mortgages equal to various percentages of the total outstanding notes. See Note 4 “Loans Receivable and the Allowance for Loan Losses” of the notes to the consolidated financial statements. As of December 31, 2016 and 2015 , FHLB borrowings were as follows: Rates Amount Minimum Maximum 2016 2015 (dollars in thousands) Due in 2016 0.50 % to 2.46 % $ — $ 22,000 Due in 2017 0.79 % to 2.78 % 30,000 10,000 Due in 2018 1.30 % to 1.60 % 19,000 19,000 Due in 2019 1.42 % to 1.85 % 27,000 17,000 Due in 2020 1.52 % to 2.25 % 32,000 12,000 Due in 2021 1.93 % to 1.93 % 7,000 7,000 Total $ 115,000 $ 87,000 On April 30, 2015 , the Company entered into a $35.0 million unsecured note payable with a correspondent bank with a maturity date of June 30, 2020 . The Company drew $25.0 million on the note prior to June 30, 2015, at which time the ability to obtain additional advances ceased. Payments of principal and interest are payable quarterly beginning September 30, 2015 . As of December 31, 2016 , $17.5 million of that note was outstanding. The note contains certain requirements, covenants and restrictions that we view to be customary for such a transaction, including those that place restrictions on additional debt and stipulate minimum capital and various operating ratios.

Income Taxes (Notes)

Income Taxes (Notes)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	Income Taxes Income taxes for the years ended December 31, 2016 , 2015 and 2014 are summarized as follows: December 31, 2016 2015 2014 (in thousands) Current: Federal $ 7,410 $ 6,147 $ 3,573 State 2,303 372 956 Deferred (2,853 ) 1,300 2,502 Total income tax provision $ 6,860 $ 7,819 $ 7,031 The income tax provisions for the years ended December 31, 2016 , 2015 and 2014 were less than the amounts computed by applying the maximum effective federal income tax rate of 35% for the years ended December 31, 2016 , 2015 , and 2014 , to the income before income taxes because of the following items: 2016 2015 2014 (dollars in thousands) Amount % of Pretax Income Amount % of Pretax Income Amount % of Pretax Income Expected provision $ 9,538 35.0 % $ 11,528 35.0 % $ 8,943 35.0 % Tax-exempt interest (3,011 ) (11.0 ) (2,817 ) (8.6 ) (2,520 ) (9.9 ) Bank-owned life insurance (477 ) (1.8 ) (438 ) (1.3 ) (385 ) (1.5 ) State income taxes, net of federal income tax benefit 1,257 4.6 333 1.0 798 3.1 Non-deductible acquisition expenses 83 0.3 691 2.1 261 1.0 General business credits (537 ) (2.0 ) (1,225 ) (3.7 ) — — Other 7 0.1 (253 ) (0.8 ) (66 ) (0.3 ) Total income tax provision $ 6,860 25.2 % $ 7,819 23.7 % $ 7,031 27.4 % Net deferred tax assets as of December 31, 2016 and 2015 consisted of the following components: December 31, 2016 2015 (in thousands) Deferred income tax assets: Allowance for loan losses $ 8,585 $ 7,449 Deferred compensation 1,982 1,909 Net operating losses (state net operating loss carryforwards) 3,838 3,560 Unrealized losses on investment securities 738 — Other real estate owned 283 146 Other 3,012 1,934 Gross deferred tax assets 18,438 14,998 Deferred income tax liabilities: Premises and equipment depreciation and amortization 4,092 3,658 Federal Home Loan Bank stock 137 133 Purchase accounting adjustments 2,352 2,717 Mortgage servicing rights 766 853 Prepaid expenses 289 194 Unrealized gains on investment securities — 2,091 Deferred loan fees 225 261 Other 216 584 Gross deferred tax liabilities 8,077 10,491 Net deferred income tax asset 10,361 4,507 Valuation allowance 3,838 3,560 Net deferred tax asset $ 6,523 $ 947 The Company has recorded a deferred tax asset for the future tax benefits of Iowa net operating loss carryforwards. The Iowa net operating loss carryforwards amounting to approximately $47.8 million will expire in various amounts from 2018 to 2037 . As of December 31, 2016 and 2015 , the Company believed it was more likely than not that all temporary differences associated with the Iowa corporate tax return would not be fully realized. Accordingly, the Company has recorded a valuation allowance to reduce the net operating loss carryforward. A valuation allowance related to the remaining deferred tax assets has not been provided because management believes it is more likely than not that the results of future operations will generate sufficient taxable income to realize the deferred tax assets. The Company had no material unrecognized tax benefits as of December 31, 2016 and 2015 .

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2016
Employee Benefit Plans [Abstract]
Compensation and Employee Benefit Plans [Text Block]	Employee Benefit Plans The Company has a salary reduction profit-sharing 401(k) plan covering all employees fulfilling minimum age and service requirements. Employee contributions to the plan are optional. Employer contributions are discretionary and may be made to the plan in an amount equal to a percentage of each participating employee’s salary. The 401(k) contribution expense for this plan totaled $1.3 million , $1.2 million and $0.7 million for the years ended December 31, 2016 , 2015 and 2014 , respectively. The Company has an employee stock ownership plan (ESOP) covering all employees fulfilling minimum age and service requirements. Employer contributions are discretionary and may be made to the plan in an amount equal to a percentage of each participating employee’s salary. The ESOP contribution expense for this plan totaled $0.8 million , $1.0 million and $0.5 million for the years ended December 31, 2016 , 2015 and 2014 , respectively. The Company has a salary continuation plan for several officers and directors. These plans provide annual payments of various amounts upon retirement or death. The Company accrues the expense for these benefits by charges to operating expense during the period the respective officer or director attains full eligibility. The amount charged to operating expense during the years ended December 31, 2016 , 2015 and 2014 totaled $0.4 million , $0.4 million and $0.3 million , respectively. To provide the retirement benefits, the Company carries life insurance policies which had cash values totaling $16.4 million , $14.7 million and $14.3 million at December 31, 2016 , 2015 and 2014 , respectively.

Stock Compensation Plans

Stock Compensation Plans	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]	Stock Compensation Plans The Company maintains the MidWest One Financial Group, Inc. 2008 Equity Incentive Plan (the “Plan”) as a means to attract, retain and reward certain designated employees and directors of, and service providers to, the Company and its subsidiaries. Under the terms of the Plan, the Company may grant a total of 750,000 total shares of the Company’s common stock as stock options, stock appreciation rights or stock awards (including restricted stock units) and may also grant cash incentive awards to eligible individuals. As of December 31, 2016 and 2015 , 431,828 and 460,757 shares, respectively, of the Company’s common stock remained available for future awards under the Plan. During 2016 , the Company recognized $731,000 of stock based compensation expense, which consisted of $731,000 of expense related to restricted stock unit grants and no expense related to stock option grants. In comparison, during 2015 , the Company recognized $634,000 of stock-based compensation expense, which consisted of $634,000 for restricted stock unit grants and no expense related to stock option grants, while total stock-based compensation expense in 2014 was $493,000 which consisted of $493,000 for restricted stock unit grants and no expense related to stock option grants. Incentive Stock Options: The Company is required to estimate the fair value of share-based payment awards on the date of grant using an option-pricing model. The value of the portion of the award that is ultimately expected to vest is recognized as compensation expense in the Company’s consolidated statements of operations over the requisite service periods using a straight-line method. The Company assumes no projected forfeitures on its stock-based compensation, since actual historical forfeiture rates on its stock-based incentive awards have been negligible. The stock options have a maximum term of ten years, an exercise price equal to the fair market value of a share of stock on the date of grant and vest 25% per year over four years , with the first vesting date being the one-year anniversary of the grant date. The following is a summary of stock option activity for the year ended December 31, 2016 : Weighted- Average Weighted- Remaining Aggregate Average Contractual Intrinsic Exercise Term in Value Shares Price Years ($000) Outstanding at December 31, 2015 22,300 $ 13.51 Granted — — Exercised (2,900 ) 18.25 Forfeited — — Expired (950 ) 20.08 Outstanding at December 31, 2016 18,450 $ 12.42 1.76 $ 465 Exercisable at December 31, 2016 18,450 $ 12.42 1.76 $ 465 During 2016 , the Company received $53,000 of cash from the exercise of stock option awards and recorded a $5,000 tax benefit from these exercises. Plan participants realized an intrinsic value of $26,000 from the exercise of these stock options during 2016 . In comparison, Plan participants realized an intrinsic value of $119,000 and $109,000 from the exercise of stock options during 2015 and 2014 , respectively. As of December 31, 2016 , there were no remaining compensation costs related to nonvested stock options that have not yet been recognized. There were no stock option awards granted in 2016 , 2015 , or 2014 . Value Information: The risk-free interest rate assumption is based upon observed interest rates for the expected term of the Company’s stock options. The expected volatility input into the model takes into account the historical volatility of the Company’s stock over the period that it has been publicly traded or the expected term of the option. The expected dividend yield assumption is based upon the Company’s historical dividend payout determined at the date of grant, if any. Restricted Stock Units: Under the Plan, the Company may grant restricted stock unit awards that vest upon the completion of future service requirements or specified performance criteria. The fair value of these awards is equal to the market price of the common stock at the date of the grant. The Company recognizes stock-based compensation expense for these awards over the vesting period, using the straight-line method, based upon the number of awards ultimately expected to vest. Each restricted stock unit entitles the recipient to receive one share of stock on the vesting date. Generally, for employee awards, the restricted stock units vest 25% per year over four years , with the first vesting date being the one-year anniversary of the grant date, or 100% upon the death or disability of the recipient, or upon change of control (as defined in the Plan) of the Company. Awards granted to directors vest 100% one year from the date of the award. If a participant terminates employment or service prior to the end of the continuous service period, the unearned portion of the stock unit award may be forfeited, at the discretion of the Company’s Compensation Committee. The Company may also issue awards that vest upon satisfaction of specified performance criteria. For these types of awards, the final measure of compensation cost is based upon the number of shares that ultimately vest considering the performance criteria. The following is a summary of nonvested restricted stock unit activity for the year ended December 31, 2016 : Weighted- Average Grant-Date Shares Fair Value Nonvested at December 31, 2015 60,858 $ 26.46 Granted 38,200 27.03 Vested (26,133 ) 25.47 Forfeited (6,875 ) 27.85 Nonvested at December 31, 2016 66,050 $ 27.04 The fair value of restricted stock unit awards that vested during 2016 was $983,000 , compared to $703,000 and $792,000 during the years ended December 31, 2015 and 2014 , respectively. As of December 31, 2016 , the total compensation costs related to nonvested restricted stock units that have not yet been recognized totaled $1,205,000 , and the weighted average period over which these costs are expected to be recognized is approximately 2.5 years .

Earnings per Share (Notes)

Earnings per Share (Notes)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Share Disclosure [Text Block]	Earnings per Share Basic per-share amounts are computed by dividing net income (the numerator) by the weighted-average number of common shares outstanding (the denominator). Diluted per-share amounts assume issuance of all common stock issuable upon conversion or exercise of other securities, unless the effect is to reduce the loss or increase the income per common share from continuing operations. Following are the calculations for basic and diluted earnings per common share: Year Ended December 31, 2016 2015 2014 (dollars in thousands, except per share amounts) Basic earnings per common share computation Numerator: Net income $ 20,391 $ 25,118 $ 18,522 Denominator: Weighted average shares outstanding 11,430,087 10,362,929 8,405,284 Basic earnings per common share $ 1.78 $ 2.42 $ 2.20 Diluted earnings per common share computation Numerator: Net income $ 20,391 $ 25,118 $ 18,522 Denominator: Weighted average shares outstanding, included all dilutive potential shares 11,456,324 10,391,323 8,433,296 Diluted earnings per common share $ 1.78 $ 2.42 $ 2.19

Regulatory Capital Requirements

Regulatory Capital Requirements and Restrictions on Subsidiary Cash	12 Months Ended
	Dec. 31, 2016
Regulatory Capital Requirements [Abstract]
Regulatory Capital Requirements under Banking Regulations [Text Block]	Regulatory Capital Requirements and Restrictions on Subsidiary Cash The Company (on a consolidated basis) and the Bank are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s and the Bank’s financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Company and the Bank must meet specific capital guidelines that involve quantitative measures of their assets, liabilities and certain off-balance-sheet items as calculated under regulatory accounting practices. The capital amounts and classifications are also subject to qualitative judgments by the regulators about components, risk weightings and other factors. Prompt corrective action provisions are not applicable to bank holding companies. Quantitative measures established by the regulations in effect on December 31, 2015, to ensure capital adequacy require the Company and the Bank to maintain minimum amounts and ratios (set forth in the table below) of total, Tier 1 capital (as defined in the regulations) and Common Equity Tier 1 Capital (as defined) to risk-weighted assets (as defined) and of Tier 1 capital (as defined) to average assets (as defined). Management believes, as of December 31, 2016 and 2015 , that the Company and the Bank met all capital adequacy requirements to which they were subject. As of December 31, 2016 , the most recent notification from the FDIC categorized the Bank as “well capitalized” under the regulatory framework for prompt corrective action then in effect. To be categorized as well capitalized under those requirements, an institution had to maintain minimum total risk-based, Tier 1 risk-based, Common Equity Tier 1 risk-based and Tier 1 leverage ratios as set forth in the table below. There are no conditions or events since the notification that management believes have changed the Bank’s category. Notwithstanding its compliance with the specified regulatory thresholds, however, the Bank’s board of directors, subsequent to December 31, 2008 , adopted a capital policy pursuant to which it will maintain a ratio of Tier 1 capital to total assets of 8% or greater, which ratio is greater than the ratio required to be well capitalized under the regulatory framework for prompt corrective action. This capital policy also provides that the Bank will maintain a ratio of total capital to total risk-weighted assets of at least 10% , which is equal to the threshold for being well capitalized under the regulatory framework for prompt corrective action. A comparison of the Company’s and the Banks’ capital with the corresponding minimum regulatory requirements in effect as of December 31, 2016 and December 31, 2015 , is presented below: Actual For Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio (dollars in thousands) At December 31, 2016: Consolidated: Total capital/risk weighted assets $ 280,396 11.65 % $ 207,661 8.625 % N/A N/A Tier 1 capital/risk weighted assets 258,304 10.73 159,508 6.625 N/A N/A Common equity tier 1 capital/risk weighted assets 234,638 9.75 123,393 5.125 N/A N/A Tier 1 leverage capital/average assets 258,304 8.75 118,040 4.000 N/A N/A MidWest One Bank: Total capital/risk weighted assets $ 286,959 11.96 % $ 206,892 8.625 % $ 239,875 10.00 % Tier 1 capital/risk weighted assets 264,871 11.04 158,917 6.625 191,900 8.00 Common equity tier 1 capital/risk weighted assets 264,871 11.04 122,936 5.125 155,919 6.50 Tier 1 leverage capital/average assets 264,871 8.98 118,000 4.000 147,500 5.00 At December 31, 2015: Consolidated: Total capital/risk weighted assets $ 263,717 11.48 % $ 183,718 8.00 % N/A N/A Tier 1 capital/risk weighted assets 244,154 10.63 137,789 6.00 N/A N/A Common equity tier 1 capital/risk weighted assets 220,567 9.60 103,342 4.50 N/A N/A Tier 1 leverage capital/average assets 244,154 8.34 117,123 4.00 N/A N/A MidWest One Bank: Total capital/risk weighted assets $ 171,583 12.53 % $ 109,578 8.00 % $ 136,972 10.00 % Tier 1 capital/risk weighted assets 154,726 11.30 82,183 6.00 109,578 8.00 Common equity tier 1 capital/risk weighted assets 154,726 11.30 61,638 4.50 89,032 6.50 Tier 1 leverage capital/average assets 154,726 8.90 69,501 4.00 86,876 5.00 Central Bank Total capital/risk weighted assets $ 102,718 11.14 % $ 73,792 8.00 % $ 92,240 10.00 % Tier 1 capital/risk weighted assets 100,017 10.84 55,344 6.00 73,792 8.00 Common equity tier 1 capital/risk weighted assets 100,017 10.84 41,508 4.50 59,956 6.50 Tier 1 leverage capital/average assets 100,017 8.44 47,412 4.00 59,265 5.00 The ability of the Company to pay dividends to its shareholders is dependent upon dividends paid by the Bank to the Company. The Bank is subject to certain statutory and regulatory restrictions on the amount of dividends it may pay. In addition, as previously noted, subsequent to December 31, 2008 , the Bank’s board of directors adopted a capital policy requiring it to maintain a ratio of Tier 1 capital to total assets of at least 8% and a ratio of total capital to risk-based capital of at least 10% . Failure to maintain these ratios also could limit the ability of the Bank to pay dividends to the Company. The Bank is required to maintain reserve balances in cash on hand or on deposit with Federal Reserve Banks. Reserve balances totaled $6.8 million and $2.0 million as of December 31, 2016 and 2015 , respectively.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure [Text Block]	Commitments and Contingencies Financial instruments with off-balance sheet risk : The Bank is a party to 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. These instruments involve, to varying degrees, elements of credit risk in excess of the amount recognized in the balance sheets. The Bank uses the same credit policies in making commitments and conditional obligations as it does for on-balance-sheet instruments. A summary of the Bank’s commitments at December 31, 2016 and 2015 , is as follows: December 31, 2016 2015 (in thousands) Commitments to extend credit $ 473,725 $ 417,927 Commitments to sell loans 4,241 3,187 Standby letters of credit 9,320 16,146 Total $ 487,286 $ 437,260 The Bank’s exposure to credit loss in the event of nonperformance by the counterparty to the financial instrument for commitments to extend credit is represented by the contractual amount of those instruments. Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Bank evaluates each customer’s creditworthiness on a case-by-case basis. The amount of collateral obtained, if deemed necessary by the Bank upon extension of credit, is based on management’s credit evaluation of the party. Collateral held varies, but may include accounts receivable, crops, livestock, inventory, property and equipment, residential real estate and income-producing commercial properties. Commitments to sell loans are agreements to sell loans held for sale to third parties at an agreed upon price. Standby letters of credit are conditional commitments issued to guarantee the performance of a customer to a third party. Those guarantees are primarily issued to support public and private borrowing arrangements and, generally, 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 Bank holds collateral, which may include accounts receivable, inventory, property, equipment and income-producing properties, that support 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 Bank would be required to fund the commitment. The maximum potential amount of future payments the Bank could be required to make is represented by the contractual amount shown in the summary above. If the commitment is funded, the Bank would be entitled to seek recovery from the customer. At both December 31, 2016 and 2015 , the amount recorded as liabilities for the Bank’s potential obligations under these guarantees was $0.2 million . Contingencies : In the normal course of business, the Bank is involved in various legal proceedings. In the opinion of management, any liability resulting from such proceedings would not have a material adverse effect on the accompanying consolidated financial statements. Concentrations of credit risk : Substantially all of the Bank’s loans, commitments to extend credit and standby letters of credit have been granted to customers in the Bank’s market areas. Although the loan portfolio of the Bank is diversified, approximately 72% of the loans are real estate loans and approximately 10% are agriculturally related. The concentrations of credit by type of loan are set forth in Note 4 “Loans Receivable and the Allowance for Loan Losses”. Commitments to extend credit are primarily related to commercial loans and home equity loans. Standby letters of credit were granted primarily to commercial borrowers. Investments in securities issued by state and political subdivisions involve certain governmental entities within Iowa and Minnesota. The carrying value of investment securities of Iowa and Minnesota political subdivisions totaled $155.6 million and $57.5 million , respectively, as of December 31, 2016 . The amount of investment securities issued by one individual municipality did not exceed $5.0 million .

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	Related Party Transactions Certain directors of the Company and certain principal officers are customers of, and have banking transactions with, the Bank in the ordinary course of business. Such indebtedness has been incurred on substantially the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with unrelated persons. The following is an analysis of the changes in the loans to related parties during the years ended December 31, 2016 and 2015 : Year Ended December 31, 2016 2015 (in thousands) Balance, beginning $ 10,247 $ 11,655 Net decrease due to change in related parties (906 ) (284 ) Advances 2,834 3,919 Collections (1,319 ) (5,043 ) Balance, ending $ 10,856 $ 10,247 None of these loans are past due, nonaccrual or restructured to provide a reduction or deferral of interest or principal because of deterioration in the financial position of the borrower. Deposits from these related parties totaled $8.3 million and $8.5 million as of December 31, 2016 and 2015 , respectively. Deposits from related parties are accepted subject to the same interest rates and terms as those from nonrelated parties. The Company has from time to time engaged Neumann Monson, P.C. (“Neumann Monson”), an architectural services firm headquartered in Iowa City for which Kevin Monson, Chairman of the Company, is President, Managing Partner and majority owner, to perform architectural and design services with respect to the Company's offices. During 2016 and 2015 , the Company paid Neumann Monson $77,000 and $254,000 , respectively, for such services. The engagement of Neumann Monson to provide the services described was reviewed by our Audit Committee, which also monitors the level of services by Neumann Monson on a periodic basis. Apart from the approval and monitoring process involving the Audit Committee, Neumann Monson was retained in the ordinary course of business, and the Company believes that such services are provided to the Company on terms no less favorable than those that would have been realized in transactions with unaffiliated parties.

Estimated Fair Value of Financi

Estimated Fair Value of Financial Instruments and Fair Value Measurements (Notes)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Disclosures [Text Block]	Estimated Fair Value of Financial Instruments and Fair Value Measurements Fair value is the price that would be received in selling an asset or paid in transferring a liability in an orderly transaction between market participants. A fair value measurement assumes that the transaction to sell the asset or transfer the liability occurs in the principal market for the asset or liability or, in the absence of a principal market, the most advantageous market for the asset or liability. The price in the principal (or most advantageous) market used to measure the fair value of the asset or liability is not adjusted for transaction costs. An orderly transaction is a transaction that assumes exposure to the market for a period prior to the measurement date to allow for marketing activities that are usual and customary for transactions involving such assets and liabilities; it is not a forced transaction. Market participants are buyers and sellers in the principal market that are (1) independent, (2) knowledgeable, (3) able to transact and (4) willing to transact. GAAP requires the use of valuation techniques that are consistent with the market approach, the income approach and/or the cost approach. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets and liabilities. The income approach uses valuation techniques to convert future amounts, such as cash flows or earnings, to a single present amount on a discounted basis. The cost approach is based on the amount that currently would be required to replace the service capacity of an asset (replacement cost). Valuation techniques should be consistently applied. Inputs to valuation techniques refer to the assumptions that market participants would use in pricing the asset or liability. Inputs may be observable, meaning those that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from independent sources, or unobservable, meaning those that reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability developed based on the best information available in the circumstances. In that regard, GAAP 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 for identical assets or liabilities in active markets that the reporting entity 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 (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 an entity’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities. It is the Company’s policy to maximize the use of observable inputs and minimize the use of unobservable inputs when developing fair value measurements. The Company is required to use observable inputs, to the extent available, in the fair value estimation process unless that data results from forced liquidations or distressed sales. 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. V aluation methods for instruments measured at fair value on a recurring basis Securities Available for Sale - The Company’s investment securities classified as available for sale include: debt securities issued by the U.S. Treasury and other U.S. Government agencies and corporations, debt securities issued by state and political subdivisions, mortgage-backed securities, collateralized mortgage obligations, corporate debt securities, and equity securities. Quoted exchange prices are available for equity securities, which are classified as Level 1. The Company utilizes an independent pricing service to obtain the fair value of debt securities. On a quarterly basis, the Company selects a sample of 30 securities from its primary pricing service and compares them to a secondary independent pricing service to validate value. In addition, the Company periodically reviews the pricing methodology utilized by the primary independent service for reasonableness. Debt securities issued by the U.S. Treasury and other U.S. Government agencies and corporations and mortgage-backed obligations are priced utilizing industry-standard models that consider various assumptions, including time value, yield curves, volatility factors, prepayment speeds, default rates, loss severity, current market and contractual prices for the underlying financial instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace, can be derived from observable data, or are supported by observable levels at which transactions are executed in the marketplace and are classified as Level 2. Municipal securities are valued using a type of matrix, or grid, pricing in which securities are benchmarked against the treasury rate based on credit rating. These model and matrix measurements are classified as Level 2 in the fair value hierarchy. On an annual basis, a group of selected municipal securities are priced by a securities dealer and that price is used to verify the primary independent service’s valuation. The following table summarizes assets measured at fair value on a recurring basis as of December 31, 2016 and 2015 . There were no liabilities subject to fair value measurement on a recurring basis as of these dates. The assets are segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value: Fair Value Measurement at December 31, 2016 Using (in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Significant Unobservable Inputs (Level 3) Assets: Available for sale debt securities: U.S. Government agencies and corporations $ 5,905 $ — $ 5,905 $ — State and political subdivisions 165,272 — 165,272 — Mortgage-backed securities 61,354 — 61,354 — Collateralized mortgage obligations 171,267 — 171,267 — Corporate debt securities 72,453 — 72,453 — Total available for sale debt securities 476,251 — 476,251 — Other equity securities 1,267 1,267 — — Total securities available for sale $ 477,518 $ 1,267 $ 476,251 $ — Fair Value Measurement at December 31, 2015 Using (in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Available for sale debt securities: U.S. Treasury securities $ 6,910 $ — $ 6,910 $ — U.S. Government agencies and corporations 26,653 — 26,653 — State and political subdivisions 183,384 — 183,384 — Mortgage-backed securities 57,062 — 57,062 — Collateralized mortgage obligations 106,404 — 106,404 — Corporate debt securities 45,566 — 45,566 — Total available for sale debt securities 425,979 — 425,979 — Other equity securities 1,262 1,262 — — Total securities available for sale $ 427,241 $ 1,262 $ 425,979 $ — There were no transfers of assets between levels of the fair value hierarchy during the years ended December 31, 2016 and 2015 . There have been no changes in valuation techniques used for any assets measured at fair value during the year ended December 31, 2016 . Changes in the fair value of available for sale securities are included in other comprehensive income to the extent the changes are not considered OTTI. OTTI tests are performed on a quarterly basis and any decline in the fair value of an individual security below its cost that is deemed to be other-than-temporary results in a write-down that is reflected directly in the Company’s consolidated statements of operations. Valuation methods for instruments measured at fair value on a nonrecurring basis Collateral Dependent Impaired Loans - From time to time, a loan is considered impaired and an allowance for credit losses is established. The specific reserves for collateral dependent impaired loans are based on the fair value of the collateral less estimated costs to sell. The fair value of collateral is determined based on appraisals. In some cases, adjustments are made to the appraised values due to various factors, including age of the appraisal, age of comparables included in the appraisal, and known changes in the market and in the collateral. Because many of these inputs are unobservable, the valuations are classified as Level 3. Other Real Estate Owned (“OREO”) - OREO represents property acquired through foreclosures and settlements of loans. Property acquired through or in lieu of foreclosure are initially recorded at fair value less estimated selling cost at the date of foreclosure, establishing a new cost basis. The Company considers third party appraisals as well as independent fair value assessments from real estate brokers or persons involved in selling OREO in determining the fair value of particular properties. Accordingly, the valuation of OREO is subject to significant external and internal judgment. The Company also periodically reviews OREO to determine whether the property continues to be carried at the lower of its recorded book value or fair value of the property, less disposal costs. Because many of these inputs are unobservable, the valuations are classified as Level 3. The following table discloses the Company’s estimated fair value amounts of its assets recorded at fair value on a nonrecurring basis. It is management’s belief that the fair values presented below are reasonable based on the valuation techniques and data available to the Company as of December 31, 2016 and 2015 , as more fully described above. Fair Value Measurement at December 31, 2016 Using (in thousands) Total Quoted Prices in Significant Other Significant Unobservable Inputs (Level 3) Assets: Collateral dependent impaired loans $ 8,774 $ — $ — $ 8,774 Other real estate owned $ 2,097 $ — $ — $ 2,097 Fair Value Measurement at December 31, 2015 Using (in thousands) Total Quoted Prices in Significant Other Significant Assets: Collateral dependent impaired loans $ 23,812 $ — $ — $ 23,812 Other real estate owned $ 8,834 $ — $ — $ 8,834 The following presents the carrying amount and estimated fair value of the financial instruments held by the Company at December 31, 2016 and 2015 . The information presented is subject to change over time based on a variety of factors. The operations of the Company are managed on a going concern basis and not a liquidation basis. As a result, the ultimate value realized from the financial instruments presented could be substantially different when actually recognized over time through the normal course of operations. Additionally, a substantial portion of the Company’s inherent value is the capitalization and franchise value of the Bank. Neither of these components has been given consideration in the presentation of fair values below. December 31, 2016 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Financial assets: Cash and cash equivalents $ 43,228 $ 43,228 $ 43,228 $ — $ — Investment securities: Available for sale 477,518 477,518 1,267 476,251 — Held to maturity 168,392 164,792 — 164,792 — Total investment securities 645,910 642,310 1,267 641,043 — Loans held for sale 4,241 4,286 — — 4,286 Loans, net 2,143,293 2,138,252 — 2,138,252 — Accrued interest receivable 13,871 13,871 13,871 — — Federal Home Loan Bank stock 12,800 12,800 — 12,800 — Financial liabilities: Deposits: Non-interest-bearing demand 494,586 494,586 494,586 — — Interest-bearing checking 1,136,282 1,136,282 1,136,282 — — Savings 197,698 197,698 197,698 — — Certificates of deposit under $100,000 326,832 324,978 — 324,978 — Certificates of deposit $100,000 and over 325,050 324,060 — 324,060 — Total deposits 2,480,448 2,477,604 1,828,566 649,038 — Federal funds purchased and securities sold under agreements to repurchase 117,871 117,871 117,871 — — Federal Home Loan Bank borrowings 115,000 114,590 — 114,590 — Junior subordinated notes issued to capital trusts 23,692 19,248 — 19,248 — Long-term debt 17,500 17,500 — 17,500 — Accrued interest payable 1,472 1,472 1,472 — — December 31, 2015 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Financial assets: Cash and cash equivalents $ 47,097 $ 47,097 $ 47,097 $ — $ — Investment securities: Available for sale 427,241 427,241 1,262 425,979 — Held to maturity 118,423 118,234 — 118,234 — Total investment securities 545,664 545,475 1,262 544,213 — Loans held for sale 3,187 3,262 — — 3,262 Loans, net 2,132,515 2,132,009 — 2,132,009 — Accrued interest receivable 13,736 13,736 13,736 — — Federal Home Loan Bank stock 9,832 9,832 — 9,832 — Financial liabilities: Deposits: Non-interest bearing demand 559,586 559,586 559,586 — — Interest-bearing checking 1,064,350 1,064,350 1,064,350 — — Savings 189,489 189,489 189,489 — — Certificates of deposit under $100,000 348,268 346,875 — 346,875 — Certificates of deposit $100,000 and over 301,828 301,521 — 301,521 — Total deposits 2,463,521 2,461,821 1,813,425 648,396 — Federal funds purchased and securities sold under agreements to repurchase 68,963 68,963 68,963 — — Federal Home Loan Bank borrowings 87,000 86,817 — 86,817 — Junior subordinated notes issued to capital trusts 23,587 18,611 — 18,611 — Long-term debt 22,500 22,500 — 22,500 — Accrued interest payable 1,507 1,507 1,507 — — • Cash and cash equivalents, federal funds purchased, securities sold under repurchase agreements, and accrued interest are instruments with carrying values that approximate fair value. • Investment securities available for sale are measured at fair value on a recurring basis. Held to maturity securities are carried at amortized cost. Fair value is based upon quoted prices, if available. If a quoted price is not available, the fair value is obtained from benchmarking the security against similar securities by using a third-party pricing service. • Loans held for sale are carried at the lower of cost or fair value, with fair value being based on recent observable loan sales. The portfolio has historically consisted primarily of residential real estate loans. • For variable-rate loans that reprice frequently and with no significant change in credit risk, fair values are based on carrying values. The fair values for other loans are determined using estimated future cash flows, discounted at the interest rates currently being offered for loans with similar terms to borrowers with similar credit quality. The Company does record nonrecurring fair value adjustments to loans to reflect (1) partial write-downs and allowances that are based on the observable market price or appraised value of the collateral or (2) the full charge-off of the loan carrying value. • The fair value of FHLB stock is estimated at its carrying value and redemption price of $100 per share. • Deposit liabilities are carried at historical cost. The fair value of non-interest bearing demand deposits, savings accounts and certain interest-bearing checking deposits is the amount payable on demand at the reporting date. The fair value of fixed maturity certificates of deposit is estimated using the rates currently offered for deposits of similar remaining maturities. If the fair value of the fixed maturity certificates of deposit is calculated at less than the carrying amount, the carrying value of these deposits is reported as the fair value. • FHLB borrowings, junior subordinated notes issued to capital trusts, and long-term debt are recorded at historical cost. The fair value of these items is estimated using discounted cash flow analysis, based on the Company’s current incremental borrowing rates for similar types of borrowing arrangements. The following presents the valuation technique(s), observable inputs, and quantitative information about the unobservable inputs used for fair value measurements of the financial instruments held by the Company at December 31, 2016 , categorized within Level 3 of the fair value hierarchy: Quantitative Information About Level 3 Fair Value Measurements (dollars in thousands) Fair Value at December 31, 2016 Valuation Techniques(s) Unobservable Input Range of Inputs Weighted Average Collateral dependent impaired loans $ 8,774 Modified appraised value Third party appraisal NM * NM * NM * Appraisal discount NM * NM * NM * Other real estate owned $ 2,097 Modified appraised value Third party appraisal NM * NM * NM * Appraisal discount NM * NM * NM * * Not Meaningful. Third party appraisals are obtained as to the value of the underlying asset, but disclosure of this information would not provide meaningful information, as the range will vary widely from loan to loan. Types of discounts considered include age of the appraisal, local market conditions, current condition of the property, and estimated sales costs. These discounts will also vary from loan to loan, thus providing a range would not be meaningful. Changes in assumptions or estimation methodologies may have a material effect on these estimated fair values.

Variable Interest Entities (Not

Variable Interest Entities (Notes)	12 Months Ended
	Dec. 31, 2016
Variable Interest Entity, Not Primary Beneficiary, Disclosures [Abstract]
Variable Interest Entity [Text Block]	Variable Interest Entities The Company had invested in certain participation certificates of loan pools which were purchased, held and serviced by a third-party independent servicing corporation. The Company's portfolio held approximately 95% of the participation interests in the pools of loans owned and serviced by States Resources Corporation (“SRC”), a third-party loan servicing organization located in Omaha, Nebraska, in which the Company participated. SRC's owner held the remaining interest. The Company did not have any ownership interest in or exert any control over SRC, and thus it was not included in the consolidated financial statements. The Company exited this line of business in June 2015. These pools of loans were purchased from large nonaffiliated banking organizations and from the FDIC acting as receiver of failed banks and savings associations. As loan pools were put out for bid (generally in a sealed bid auction), SRC’s due diligence teams evaluated the loans and determined their interest in bidding on the pool. After the due diligence, the Company’s management reviewed the status and decided if it wished to continue in the process. If the decision to consider a bid was made, SRC conducted additional analysis to determine the appropriate bid price. This analysis involved discounting loan cash flows with adjustments made for expected losses, changes in collateral values as well as targeted rates of return. A cost or investment basis was assigned to each individual loan on a cents-per-dollar (discounted price) basis based on SRC’s assessment of the recovery potential of each loan. Once a bid was awarded to SRC, the Company assumed the risk of profit or loss, but did so on a non-recourse basis so the risk was limited to its initial investment. The extent of the risk was also dependent upon: the debtor or guarantor’s financial condition, the possibility that a debtor or guarantor may file for bankruptcy protection, SRC’s ability to locate any collateral and obtain possession, the value of such collateral, and the length of time it took to realize the recovery either through collection procedures, legal process, or resale of the loans after a restructure. Loan pool participations were shown on the Company’s consolidated balance sheets as a separate asset category. The original carrying value or investment basis of loan pool participations was the discounted price paid by the Company to acquire its interests, which, as noted, was less than the face amount of the underlying loans. The Company’s investment basis was reduced as SRC recovered principal on the loans and remitted its share to the Company or as loan balances were written off as uncollectible.

Operating Segments (Notes)

Operating Segments (Notes)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Segment Reporting Disclosure [Text Block]	Operating Segments The Company’s activities are considered to be a single industry segment for financial reporting purposes. The Company is engaged in the business of commercial and retail banking, investment management and insurance services with operations throughout central and eastern Iowa, the Twin Cities area of Minnesota and Wisconsin, and Florida. Substantially all income is derived from a diverse base of commercial, mortgage and retail lending activities, and investments.

Branch Sales (Notes)

Branch Sales (Notes)	12 Months Ended
	Dec. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Disposal Groups, Including Discontinued Operations, Disclosure [Text Block]	Branch Sales On September 10, 2015, MidWestOne Bank, a wholly owned subsidiary of the Company, entered into an agreement to sell its Ottumwa, Iowa branch to Peoples State Bank headquartered in Albia, Iowa, a unit of Peoples Tri-County BanCorp. Peoples State Bank assumed approximately $33.0 million in deposits and $17.1 million in loans on the sale completion date of December 4, 2015, and the Company realized a net gain of $0.7 million , which is included on the Consolidated Statements of Operation in Other gain. On September 24, 2015, Central Bank, a wholly owned subsidiary of the Company, entered into an agreement to sell its Barron and Rice Lake, Wisconsin branches to Citizens Community Federal Bank headquartered in Altoona, Wisconsin, a unit of Citizens Community Bancorp, Inc. of Eau Claire, Wisconsin. Citizens Community Federal Bank assumed approximately $27.6 million in deposits and $14.2 million in loans. The transaction was completed on February 5, 2016, and the Company realized a net gain of $0.7 million , which is included on the Consolidated Statements of Operations in Other gain. On May 9, 2016, the Bank entered into an agreement to sell its Davenport, Iowa branch to CBI Bank and Trust (“CBI Bank”) headquartered in Muscatine, Iowa, a unit of Central Bancshares, Inc. of Muscatine, Iowa. CBI Bank assumed approximately $12.0 million in deposits and $33.0 million in loans on the sale completion date of August 5, 2016, and the Company realized a net gain of $0.7 million , which is included on the Consolidated Statements of Operations in Other gain.

Parent Company Only Financial I

Parent Company Only Financial Information	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Financial Information of Parent Company Only Disclosure [Text Block]	Parent Company Only Financial Information The following is condensed financial information of MidWest One Financial Group, Inc. as of December 31, 2016 and 2015 (parent company only): As of December 31, 2016 2015 (in thousands) Balance Sheets Assets Cash $ 2,621 $ 4,489 Investment in subsidiaries 336,937 331,612 Investment securities available for sale 326 300 Investment securities held to maturity 743 743 Income tax receivable 1,479 571 Other assets 4,947 4,976 Total assets $ 347,053 $ 342,691 Liabilities and Shareholders’ Equity Liabilities: Junior subordinated notes issued to capital trusts $ 23,692 $ 23,587 Long-term debt 17,500 22,500 Deferred income taxes 84 113 Other liabilities 321 313 Total liabilities 41,597 46,513 Shareholders’ equity: Capital stock, preferred — — Capital stock, common 11,713 11,713 Additional paid-in capital 163,667 163,487 Treasury stock (5,766 ) (6,331 ) Retained earnings 136,975 123,901 Accumulated other comprehensive income (1,133 ) 3,408 Total shareholders’ equity 305,456 296,178 Total liabilities and shareholders’ equity $ 347,053 $ 342,691 The following is condensed financial information of MidWest One Financial Group, Inc.for the years ended December 31, 2016 , 2015 , and 2014 (parent company only): Year Ended December 31, 2016 2015 2014 (in thousands) Statements of Income Dividends received from subsidiaries $ 12,508 $ 53,511 $ 8,500 Interest income and dividends on investment securities 31 30 49 Interest and discount on loan pool participations — (69 ) (293 ) Investment securities gains — 188 — Loss on sale of loan pool participations — (455 ) — Interest on debt (1,305 ) (1,135 ) (281 ) Operating expenses (1,966 ) (5,233 ) (2,351 ) Income before income taxes and equity in subsidiaries’ undistributed income 9,268 46,837 5,624 Income tax benefit (1,245 ) (1,951 ) (807 ) Income before equity in subsidiaries’ undistributed income 10,513 48,788 6,431 Equity in subsidiaries’ undistributed income 9,878 (23,670 ) 12,091 Net income $ 20,391 $ 25,118 $ 18,522 The following is condensed financial information of MidWest One Financial Group, Inc. for the years ended December 31, 2016 , 2015 , and 2014 (parent company only): Year Ended December 31, 2016 2015 2014 (in thousands) Statements of Cash Flows Cash flows from operating activities: Net income $ 20,391 $ 25,118 $ 18,522 Adjustments to reconcile net income to net cash provided by operating activities: Undistributed (earnings) loss of subsidiaries, net of dividends and distributions (9,878 ) 23,670 (12,091 ) Amortization of premium on junior subordinated notes issued to capital trusts 105 73 — Deferred income taxes (35 ) 617 330 Investment securities gain — (188 ) — Stock based compensation 731 634 493 (Increase) decrease in other assets (879 ) 518 (488 ) Increase (decrease) in other liabilities 8 (907 ) 550 Net cash provided by operating activities 10,443 49,535 7,316 Cash flows from investing activities Proceeds from sales of available for sale securities 1 1,173 2 Purchase of available for sale securities (9 ) (14 ) (29 ) Proceeds from maturities and calls of held to maturity securities — 246 — Loan participation pools, net — 1,964 1,445 Net cash acquired in business combination — (62,902 ) — Investment in subsidiary - Central Bank — (3,000 ) — Net cash provided by (used in) investing activities (8 ) (62,533 ) 1,418 Cash flows from financing activities: Stock options exercised 14 158 282 Repurchase of common stock — — (3,987 ) Redemption of subordinated note payable — (12,669 ) — Proceeds from long-term debt — 25,000 — Payments on long-term debt (5,000 ) (2,500 ) — Issuance of common stock, net of expenses — 7,900 — Dividends paid (7,317 ) (6,344 ) (4,868 ) Net cash provided by (used in) financing activities (12,303 ) 11,545 (8,573 ) Increase (decrease) in cash (1,868 ) (1,453 ) 161 Cash Balance: Beginning 4,489 5,942 5,781 Ending $ 2,621 $ 4,489 $ 5,942

Subsequent Events (Notes)

Subsequent Events (Notes)	12 Months Ended
	Dec. 31, 2016
Subsequent Events [Abstract]
Subsequent Events [Text Block]	Subsequent Events Management evaluated subsequent events through the date the consolidated financial statements were issued. Events or transactions occurring after December 31, 2016 , but prior to the date the consolidated financial statements were issued, that provided additional evidence about conditions that existed at December 31, 2016 have been recognized in the consolidated financial statements for the period ended December 31, 2016 . Events or transactions that provided evidence about conditions that did not exist at December 31, 2016 , but arose before the consolidated financial statements were issued, have not been recognized in the consolidated financial statements for the period ended December 31, 2016 . On January 25, 2017 , the board of directors of the Company declared a cash dividend of $0.165 per share payable on March 15, 2017 to shareholders of record as of the close of business on March 1, 2017 . On February 17, 2017 the Company announced its plans to expand into the Denver, Colorado market area through the hiring of four bankers and the establishment of a full-service branch in Denver. The Company expects its first Denver-area full service bank office will open in late spring of 2017 once all arrangements and regulatory approvals are secured.

Quarterly Results of Operations

Quarterly Results of Operations (unaudited)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information [Text Block]	Quarterly Results of Operations (unaudited) Three Months Ended December 31 September 30 June 30 March 31 (in thousands, except per share amounts) 2016 Interest income $ 27,914 $ 27,891 $ 28,038 $ 28,485 Interest expense 3,384 3,310 3,098 2,930 Net interest income 24,530 24,581 24,940 25,555 Provision for loan losses 4,742 1,005 1,171 1,065 Noninterest income 5,720 5,714 5,595 6,405 Noninterest expense 21,106 20,439 22,815 23,446 Income before income taxes 4,402 8,851 6,549 7,449 Income tax expense 532 2,629 1,794 1,905 Net income $ 3,870 $ 6,222 $ 4,755 $ 5,544 Net income per common share - basic $ 0.34 $ 0.54 $ 0.42 $ 0.49 Net income per common share - diluted $ 0.34 $ 0.54 $ 0.42 $ 0.48 2015 Interest income $ 29,044 $ 29,989 $ 25,185 $ 16,482 Interest expense 2,716 3,230 2,462 2,240 Net interest income 26,328 26,759 22,723 14,242 Provision for loan losses 1,490 2,141 901 600 Noninterest income 6,638 5,460 5,087 4,008 Noninterest expense 21,809 20,342 19,846 11,179 Income before income taxes 9,667 9,736 7,063 6,471 Income tax expense 1,429 2,121 2,594 1,675 Net income $ 8,238 $ 7,615 $ 4,469 $ 4,796 Net income per common share - basic $ 0.72 $ 0.67 $ 0.43 $ 0.57 Net income per common share - diluted $ 0.72 $ 0.67 $ 0.42 $ 0.57

Significant Accounting Policies

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Use of Estimates, Policy [Policy Text Block]	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amount of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The U.S. economic environment in recent years has increased the degree of uncertainty inherent in these estimates. Certain significant estimates : The allowance for loan losses, fair value of assets acquired and liabilities assumed in a business combination, annual impairment testing of goodwill, and the fair values of investment securities and other financial instruments involve certain significant estimates made by management. These estimates are reviewed by management routinely, and it is reasonably possible that circumstances that exist may change in the near-term future and that the effect could be material to the consolidated financial statements.
Consolidation, Policy [Policy Text Block]	The consolidated financial statements include the accounts of MidWest One Financial Group, Inc., a bank holding company, and its wholly-owned subsidiary MidWest One Bank, which is a state chartered bank whose primary federal regulator is the FDIC, and MidWest One Insurance Services, Inc. All significant inter-company accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior periods’ consolidated financial statements to present them on a basis comparable with the current period’s consolidated financial statements. Trust assets, other than cash deposits held by the Bank in a fiduciary or agency capacity for its customers, are not included in the accompanying consolidated financial statements because such accounts are not assets of the the Bank. In the normal course of business, the Company may enter into a transaction with a variable interest entity (“VIE”). VIEs are legal entities whose investors lack the ability to make decisions about the entity’s activities, or whose equity investors do not have the right to receive the residual returns of the entity. The applicable accounting guidance requires the Company to perform ongoing quantitative and qualitative analysis to determine whether it must consolidate any VIE. The Company does not have any ownership interest in or exert any control over any VIE, and thus no VIEs are included in the consolidated financial statements. Investments in non-marketable loan participation certificates for which the Company does not have the ability to exert significant influence are accounted for using the cost method.
Cash and Cash Equivalents, Policy [Policy Text Block]	For purposes of reporting cash flows, cash and due from banks includes cash on hand, amounts due from banks, and federal funds sold. Cash flows from portfolio loans originated by the Bank, deposits, federal funds purchased, and securities sold under agreements to repurchase are reported net.
Marketable Securities, Policy [Policy Text Block]	Certain debt securities that the Company has the positive intent and ability to hold to maturity are classified as held to maturity and recorded at amortized cost. Securities not classified as held to maturity, including equity securities with readily determinable fair values, are classified as available for sale and recorded at fair value, with unrealized gains and losses excluded from earnings and reported in other comprehensive income. The Company employs valuation techniques which utilize observable inputs when those inputs are available. These observable inputs reflect assumptions market participants would use in pricing the security, developed based on market data obtained from sources independent of the Company. When such information is not available, the Company employs valuation techniques which utilize unobservable inputs, or those which reflect the Company’s own assumptions about assumptions that market participants would use, based on the best information available in the circumstances. These valuation methods typically involve cash flow and other financial modeling techniques. Changes in underlying factors, assumptions, estimates, or other inputs to the valuation techniques could have a material impact on the Company’s future financial condition and results of operations. Fair value measurements are required to be classified as Level 1 (quoted prices), Level 2 (based on observable inputs) or Level 3 (based on unobservable inputs) discussed in more detail in Note 20 to the consolidated financial statements. Available for sale securities are recorded at fair value with unrealized gains and losses excluded from earnings and reported as a separate component of shareholders’ equity until realized. Purchase premiums and discounts are recognized in interest income using the interest method over the terms of the securities. Declines in the fair value of held to maturity and available for sale securities below their cost that are deemed to be other than temporary are reflected in earnings as realized losses. In determining whether other than temporary impairment exists, management considers whether: (1) we have the intent to sell the security; (2) it is more likely than not that we will be required to sell the security before recovery of the amortized cost basis; and (3) we do not expect to recover the entire amortized cost basis of the security. Gains and losses on the sale of securities are recorded on the trade date and are determined using the specific identification method.
Finance, Loan and Lease Receivables, Held-for-investment, Policy [Policy Text Block]	Loans are stated at the principal amount outstanding, net of deferred loan fees and costs and allowance for loan losses. Interest on loans is credited to income as earned based on the principal amount outstanding. Deferred loan fees and costs are amortized using the level yield method over the remaining maturities on the loans. The accrual of interest on mortgage and commercial loans is discontinued at the time the loan is 120 days past due, unless the credit is well secured and in process of collection. Credit card loans and other personal loans are typically charged off no later than 180 days past due. Past due status is based on contractual terms of the loan. In all cases, loans are placed on nonaccrual or charged off at an earlier date, if collection of principal or interest is considered doubtful. All interest accrued but not collected for loans that are placed on nonaccrual or charged off is reversed against interest income. The interest on these loans is accounted for on the cash-basis or cost-recovery method, until qualifying for return to accrual. Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured.
Loans Acquired in Transfer, Policy [Policy Text Block]	All purchased loans (nonimpaired and impaired) are initially measured at fair value as of the acquisition date in accordance with applicable authoritative accounting guidance. Credit discounts are included in the determination of fair value. An allowance for loan losses is not recorded at the acquisition date for loans purchased. Individual loans acquired through the completion of a transfer, including loans that have evidence of deterioration of credit quality since origination and for which it is probable, at acquisition, that the Company will be unable to collect all contractually required payments receivable, are referred to herein as “purchased credit impaired loans.” In determining the acquisition date fair value and estimated credit losses of purchased credit impaired loans, and in subsequent accounting, the Company accounts for loans individually. Contractually required payments for interest and principal that exceed the undiscounted cash flows expected at acquisition, or the “nonaccretable difference,” are not recognized as a yield adjustment or as a loss accrual or valuation allowance. Expected cash flows at the purchase date in excess of the fair value of loans, if any, are recorded as interest income over the expected life of the loans if the timing and amount of future cash flows are reasonably estimable. Subsequent to the purchase date, increases in cash flows over those expected at the purchase date are recognized as interest income prospectively. The present value of any decreases in expected cash flows after the purchase date is recognized by recording an allowance for loan losses and a provision for loan losses. If the Company does not have the information necessary to reasonably estimate cash flows to be expected, it may use the cost-recovery method or cash-basis method of income recognition. Subsequent to the purchase date, increases in cash flows over those expected at the purchase date are recognized as interest income prospectively. Subsequent to the purchase date, the methods utilized to estimate the required allowance for loan losses for these loans are similar to originated loans. The remaining differences between the purchase price and the unpaid balance at the date of acquisition are recorded in interest income over the life of the loan.
FDIC Indemnification Asset [Policy Text Block]	As part of the Central transaction, the Company assumed loss-share or similar credit protection agreements with the FDIC. Loans and other real estate owned covered under these agreements are reported respectively in loans or other real estate owned. The loss-share assets are measured separately from the loan portfolios because they are not contractually embedded in the loans and are not transferable with the loans should the Company choose to dispose of them. Fair values at the acquisition dates were estimated based on projected collections from the FDIC. When cash flow estimates are adjusted downward for a particular loan, the FDIC indemnification asset is increased and an allowance for loan losses is established . When cash flow estimates are adjusted upward for a particular loan, the FDIC indemnification asset is decreased, the Company accounts for the associated decrease in the indemnification asset by amortizing the change over the lesser of the contractual term of the indemnification agreement or the remaining life of the indemnified asset. When cash flow estimates are adjusted downward for covered foreclosed real estate, the FDIC indemnification asset is increased. When cash flow estimates are adjusted upward for covered foreclosed real estate, the FDIC indemnification asset is decreased. Any write-down after the transfer to covered foreclosed real estate is reversed. In applicable scenarios, the claw-back liability for amounts owed to the FDIC for better than expected performance will increase or decrease accordingly. The related FDIC indemnification assets are included in other assets, and there was no impairment recorded on such assets in 2016 .
Finance, Loan and Lease Receivables, Held-for-sale, Policy [Policy Text Block]	Loans originated and intended for sale in the secondary market 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. Mortgage loans held for sale are generally sold with the mortgage servicing rights retained. Gains or losses on sales of mortgage loans are recognized based on the difference between the selling price plus the value of servicing rights, less the carrying value of the related mortgage loans sold.
Loans and Leases Receivable, Allowance for Loan Losses Policy [Policy Text Block]	The allowance for loan losses is established through a provision for loan losses charged to earnings. Loan losses are charged against the allowance when management believes the uncollectibility of a loan balance is confirmed. Subsequent recoveries, if any, are credited to the allowance. The allowance for loan losses is evaluated on a quarterly basis by management and is based upon management’s periodic review of the collectiblity 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. The allowance consists of specific and general components. The specific component relates to loans that are classified as doubtful, substandard or special mention. For such loans that are also classified as impaired as well as any loan (regardless of classification) meeting the definition of a troubled debt restructuring, an allowance is established when the discounted cash flows (or collateral value or observable market price) of the impaired loan are lower than the carrying value of that loan. The general component covers loans not classified as impaired and is based on historical loss experience adjusted for qualitative factors. A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual 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. Impairment is measured on a loan-by-loan basis by either the present value of 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 loans (with individual balances less than $100,000) are not evaluated for impairment The Allowance for Loan and Lease Losses The Company requires the maintenance of an adequate ALLL in order to cover estimated probable losses without eroding the Company’s capital base. Calculations are done at each quarter end, or more frequently if warranted, to analyze the collectability of loans and to ensure the adequacy of the allowance. In line with FDIC directives, the ALLL calculation does not include consideration of loans held for sale or off-balance-sheet credit exposures (such as unfunded letters of credit). Determining the appropriate level for the ALLL relies on the informed judgment of management, and as such, is subject to inexactness. Given the inherently imprecise nature of calculating the necessary ALLL, the Company’s policy permits the actual ALLL to be between 20% above and 5% below the “indicated reserve.”
Transfers and Servicing of Financial Assets, Servicing of Financial Assets, Policy [Policy Text Block]	Revenue from the origination and sale of loans in the secondary market is recognized upon the transfer of financial assets and accounted for as sales when control over the assets has been surrendered. The Company also sells participation interests in some large loans originated, to non-affiliated entities. Control over transferred assets is deemed to be surrendered when: (1) the assets have been isolated from the Company; (2) the transferee has 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 trivial 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.
Revenue Recognition, Sales of Services [Policy Text Block]	Trust fees, deposit account service charges and other fees are recognized when payment is received for the services (cash basis), which generally occurs at the time the services are provided.
Off-Balance-Sheet Credit Exposure, Policy [Policy Text Block]	In the ordinary course of business, the Company has entered into commitments to extend credit, including commitments under credit card arrangements, commercial letters of credit and standby letters of credit. Such financial instruments are recorded when they are funded. The Company records a liability to the extent losses on its commitments to lend are probable.
Property, Plant and Equipment, Policy [Policy Text Block]	Land is carried at cost. Premises and equipment are stated at cost less accumulated depreciation. The estimated useful lives and primary method of depreciation for the principal items are as follows: Years Type of Assets Minimum Maximum Depreciation Method Buildings and leasehold improvements 10 - 30 Straight-line Furniture and equipment 3 - 10 Straight-line Charges for maintenance and repairs are expensed as incurred. When assets are retired or disposed of the related cost and accumulated depreciation are removed from the respective accounts and the resulting gain or loss is recorded.
Loans and Leases Receivable, Real Estate Acquired Through Foreclosure, Policy [Policy Text Block]	Real estate properties acquired through or in lieu of foreclosure are initially recorded at fair value less estimated selling cost at the date of foreclosure, establishing a new cost basis. Fair value is determined by management by obtaining appraisals or other market value information at least annually. Any write-downs in value at the date of acquisition are charged to the allowance for loan losses. After foreclosure, valuations are periodically performed by management by obtaining updated appraisals or other market value information. Any subsequent write-downs are recorded as a charge to operations, if necessary, to reduce the carrying value of a property to the updated fair value less estimated selling cost. Net costs related to the holding of properties are included in noninterest expense.
Goodwill and Intangible Assets, Policy [Policy Text Block]	Goodwill and other intangibles : Goodwill is the excess of the purchase price over the fair value of identifiable net assets acquired in business combinations accounted for as purchases. Under ASC Topic 350, goodwill of a reporting unit is tested for impairment on an annual basis, or between annual tests if an event occurs or circumstances change that would reduce the fair value of a reporting unit below its carrying amount. The Company's annual assessment is done at the unit level. The Company did not recognize impairment losses during the year ended December 31, 2016 . Any future impairment will be recorded as noninterest expense in the period of assessment. Certain other intangible assets that have finite lives are amortized over the remaining useful lives.
Transfers and Servicing of Financial Assets, Servicing of Financial Assets, Policy [Policy Text Block]	Mortgage servicing rights are recorded at fair value based on assumptions through a third-party valuation service. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the servicing cost per loan, the discount rate, the escrow float rate, an inflation rate, ancillary income, prepayment speeds and default rates and losses.
Bank Owned Life Insurance [Policy Text Block]	Bank-owned life insurance is carried at cash surrender value, net of surrender and other charges, with increases/decreases reflected as income/expense in the consolidated statements of operations.
Pension and Other Postretirement Plans, Pensions, Policy [Policy Text Block]	Deferred benefits under a salary continuation plan are charged to expense during the period in which the participating employees attain full eligibility.
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	Compensation expense for share based awards is recorded over the vesting period at the fair value of the award at the time of grant. The exercise price of options or fair value of nonvested shares granted under the Company’s incentive plans is equal to the fair market value of the underlying stock at the grant date. The Company assumes no projected forfeitures on its stock based compensation, since actual historical forfeiture rates on its stock-based incentive awards has been negligible.
Income Tax, Policy [Policy Text Block]	The Company and/or its subsidiaries currently file tax returns in all states and local taxing jurisdictions which impose corporate income, franchise or other taxes where it operates. The methods of filing and the methods for calculating taxable and apportionable income vary depending upon the laws of the taxing jurisdiction. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amount of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized. In accordance with ASC 740, Income Taxes , the Company recognizes a tax position as a benefit only if it is more likely than not that the tax position would be sustained in a tax examination, with a tax examination being presumed to occur. The amount recognized is the largest amount of tax benefit that is greater than 50% likely of being realized upon examination. For tax positions not meeting the more likely than not test, no tax benefit is recorded. The Company recognizes interest and/or penalties related to income tax matters in income tax expense. There were no material unrecognized tax benefits or any interest or penalties on any unrecognized tax benefits as of December 31, 2016 and 2015 .
Stockholders' Equity, Policy [Policy Text Block]	On July 17, 2014 , the board of directors of the Company approved a new share repurchase program, allowing for the repurchase of up to $5.0 million of stock through December 31, 2016 . The new repurchase program replaced the Company's prior repurchase program, pursuant to which the Company had repurchased approximately $3.7 million of common stock since January 1, 2013. Pursuant to the new program, the Company could continue to repurchase shares from time to time in the open market, and the method, timing and amounts of repurchase were solely in the discretion of the Company's management. The repurchase program did not require the Company to acquire a specific number of shares. Therefore, the amount of shares repurchased pursuant to the program depended on several factors, including market conditions, capital and liquidity requirements, and alternative uses for cash available. In 2014, we repurchased 165,766 shares of common stock at a cost of $4.0 million . In 2015 we repurchased no shares of common stock. Of the $5.0 million of stock authorized under the repurchase plan, $3.8 million remained available for possible future repurchases as of December 31, 2015. No shares were repurchased under this plan during 2016. On July 21, 2016 , the board of directors of the Company approved a share repurchase program, allowing for the repurchase of up to $5.0 million of stock through December 31, 2018 . During 2016 the Company repurchased no common stock under this plan, thus, of the $5.0 million of stock authorized under the repurchase plan, $5.0 million remained available for possible future repurchases as of December 31, 2016 . On May 1, 2015, in connection with the Central merger, the Company issued 2,723,083 shares of its common stock. On June 22, 2015, the Company entered into a Securities Purchase Agreement with certain institutional accredited investors, pursuant to which, on June 23, 2015, the Company sold an aggregate of 300,000 newly issued shares of the Company’s common stock, at a purchase price of $28.00 per share. Each of the purchasers was an existing shareholder of the Company.
Comprehensive Income, Policy [Policy Text Block]	Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income. Certain changes in assets and liabilities, such as unrealized gains and losses on available-for-sale securities, are reported as a separate component of shareholders’ equity on the consolidated balance sheets, and are disclosed in the consolidated statements of comprehensive income. The components of accumulated other comprehensive income, included in shareholders’ equity, net of tax, are as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Unrealized gains on securities available for sale, net of tax $ (1,133 ) $ 3,408 $ 5,322 Accumulated other comprehensive income, net of tax $ (1,133 ) $ 3,408 $ 5,322
New Accounting Pronouncements, Policy [Policy Text Block]	In May 2014, the FASB issued Accounting Standards Update No. 2014-09, Revenue from Contract with Customers (Topic 606). The guidance in this update affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets unless those contracts are within the scope of other standards (for example, insurance contracts or lease contracts). The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve that core principle, an entity should apply the following five steps: 1) identify the contracts(s) with the customer; 2) identify the performance obligations in the contract; 3) determine the transaction price; 4) allocate the transaction price to the performance obligations in the contract; and 5) recognize revenue when (or as) the entity satisfies a performance obligation. The guidance also specifies the accounting for some costs to obtain or fulfill a contract with a customer. For a public entity, the amendments in this update are effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application is not permitted. The adoption of this amendment is not expected to have a significant effect on the Company’s consolidated financial statements. In August 2014, the FASB issued Accounting Standards Update No. 2014-15, Presentation of Financial Statements - Going Concern (Subtopic 205-40): Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The amendments in this update provide guidance in GAAP about management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. In doing so, the amendment should reduce diversity in the timing and content of footnote disclosures. Disclosures are required if it is probable an entity will be unable to meet its obligations within the look-forward period of twelve months after the financial statements are made available. Incremental substantial doubt disclosure is required if the probability is not mitigated by management’s plans. The new standard applies to all entities for the first annual period ending after December 15, 2016, and interim periods thereafter. The adoption of this standard is not expected to have a significant effect on the Company’s consolidated financial statements. In July 2015, the FASB announced a delay to the effective date of Accounting Standards Update No. 2015-09, Revenue from Contract with Customers (Topic 606). Reporting entities may choose to adopt the standard as of the original date, or take advantage of a one-year delay, which the Company intends to take advantage of. For a public entity, the revised effective date is for annual reporting periods beginning after December 15, 2017, including interim periods within that reporting period. Early application is not permitted prior to the original effective date. The adoption of this amendment is not expected to have a significant effect on the Company’s consolidated financial statements. In January 2016, the FASB issued Accounting Standards Update No. 2016-01, Financial Instruments-Overall: Recognition and Measurement of Financial Assets and Financial Liabilities. The guidance in this update makes changes to the current GAAP model primarily affecting the accounting for equity investments, financial liabilities under the fair value option, and the presentation and disclosure requirements for financial instruments. In addition, the FASB clarified guidance related to the valuation allowance assessment when recognizing deferred tax assets resulting from unrealized losses on available-for-sale debt securities. The accounting for other financial instruments, such as loans, investments in debt securities, and financial liabilities is largely unchanged. The treatment of gains and losses for all equity securities, including those without a readily determinable market value, is expected to result in additional volatility in the income statement, with the loss of mark to market via equity for these investments. Additionally, changes in the allowable method for determining the fair value of financial instruments in the financial statement footnotes (“exit price” only) will likely require changes to current methodologies of determining these values, and how they are disclosed in the financial statement footnotes. The new standard applies to public business entities in fiscal years beginning after December 15, 2017, including interim periods within those fiscal years, with early adoption permitted. The adoption of this amendment is not expected to have a significant effect on the Company’s consolidated financial statements. In February 2016, the FASB issued Accounting Standards Update No. 2016-02, Leases (Topic 842) . The guidance in this update is meant to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. The core principle of Topic 842 is that a lessee should recognize the assets and liabilities that arise from leases. All leases create an asset and a liability for the lessee in accordance with FASB Concepts Statement No. 6, Elements of Financial Statements , and, therefore, recognition of those lease assets and lease liabilities represents an improvement over previous GAAP, which did not require lease assets and lease liabilities to be recognized for most leases. Disclosures are required by lessees and lessors to meet the objective of enabling users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. To meet that objective, qualitative disclosures along with specific quantitative disclosures are required. The new standard applies to public business entities in fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. The Company is still evaluating the effect of this guidance on the Company’s consolidated financial statements, and is currently gathering all leases for analysis. In March 2016, the FASB issued Accounting Standards Update No. 2016-09, Compensation - Stock Compensation (Topic 718) . The guidance involves several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The new standard applies to public business entities for annual periods beginning after December 15, 2016, including interim periods within those annual periods, with early adoption permitted. An entity that elects early adoption must adopt all of the amendments in the same period. The adoption of this amendment is not expected to have a significant effect on the Company’s consolidated financial statements. In June 2016, the FASB issued Accounting Standards Update No. 2016-13, Financial Instruments-Credit Losses (Topic 326) - Measurement of Credit Losses on Financial Instruments . The new guidance introduces an approach based on expected losses to estimate credit losses on certain types of financial instruments. It also modifies the impairment model for available-for-sale debt securities and provides for a simplified accounting model for purchased financial assets with credit deterioration since their origination. The amendment requires the use of a new model covering current expected credit losses (CECL), which will apply to: (1) financial assets subject to credit losses and measured at amortized cost, and (2) certain off-balance sheet credit exposures. Upon initial recognition of the exposure, the CECL model requires an entity to estimate the credit losses expected over the life of an exposure (or pool of exposures). The estimate of expected credit losses (ECL) should consider historical information, current information, and reasonable and supportable forecasts, including estimates of prepayments. The new guidance also amends the current available for sale (AFS) security OTTI model for debt securities. The new model will require an estimate of ECL only when the fair value is below the amortized cost of the asset. The length of time the fair value of an AFS debt security has been below the amortized cost will no longer impact the determination of whether a credit loss exists. As such, it is no longer an other-than-temporary model. Finally, the purchased financial assets with credit deterioration (PCD) model applies to purchased financial assets (measured at amortized cost or fair value) that have experienced more than insignificant credit deterioration since origination. This represents a change from the scope of what are considered purchased credit-impaired assets under today’s model. Different than the accounting for originated or purchased assets that do not qualify as PCD, the initial estimate of expected credit losses for a PCD would be recognized through an allowance for loan and lease losses with an offset to the cost basis of the related financial asset at acquisition. The new standard applies to public business entities that are SEC filers in fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, with early adoption permitted for fiscal years beginning after December 31, 2018, including interim periods within those fiscal years. The Company is still evaluating the effect of this guidance on the Company’s consolidated financial statements, and is in the process of organizing working groups to analyze the various components of the ASU. In August 2016, the FASB issued Accounting Standards Update No. 2016-15, Statement of Cash Flows (Topic 230) - Classification of Certain Cash Receipts and Cash Payments, a consensus of the FASB Emerging Issues Task Force . The new guidance addresses diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows under Topic 230, Statement of Cash Flows, and other topics. This update addresses eight specific cash flow issues with the objective of reducing the existing diversity in practice. The amendments in this update apply to all entities, including both business entities and not-for-profit entities that are required to present a statement of cash flows under Topic 230. The update applies to public business entities in fiscal years beginning after December 15, 2017, including interim periods within those fiscal years, with early adoption permitted, and the Company has elected to adopt the guidance effective September 30, 2016, and did not have a significant effect on the Company’s consolidated financial statements. In January 2017, the FASB issued Accounting Standards Update No. 2017-04, Intangibles-Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment. The new guidance removes Step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. A goodwill impairment will now be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. All other goodwill impairment guidance will remain largely unchanged. The update applies to public business entities that are SEC filers in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The adoption of this amendment is not expected to have a significant effect on the Company’s consolidated financial statements.
Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts [Policy Text Block]	Charge-off Policy The Company requires a loan to be charged-off, in whole or in part, as soon as it becomes apparent that some loss will be incurred, or when its collectability is sufficiently questionable that it no longer is considered a bankable asset. The primary considerations when determining if and how much of a loan should be charged-off are as follows: (1) the potential for future cash flows; (2) the value of any collateral; and (3) the strength of any co-makers or guarantors. When it is determined that a loan requires a partial or full charge-off, a request for approval of a charge-off is submitted to the Company's President, Executive Vice President and Chief Credit Officer, and the Senior Regional Loan Officer. The Bank's board of directors formally approves all loan charge-offs. Once a loan is charged-off, it cannot be restructured and returned to the Company's books.
Loans and Leases Receivable, Troubled Debt Restructuring Policy [Policy Text Block]	Loans Reviewed Individually for Impairment The Company identifies loans to be reviewed and evaluated individually for impairment based on current information and events and the probability that the borrower will be unable to repay all amounts due according to the contractual terms of the loan agreement. Specific areas of consideration include: size of credit exposure, risk rating, delinquency, nonaccrual status, and loan classification. The level of individual impairment is measured using one of the following methods: (1) the fair value of the collateral less costs to sell; (2) the present value of expected future cash flows, discounted at the loan's effective interest rate; or (3) the loan's observable market price. Loans that are deemed fully collateralized or have been charged down to a level corresponding with any of the three measurements require no assignment of reserves from the ALLL. A loan modification is a change in an existing loan contract that has been agreed to by the borrower and the Bank, which may or may not be a troubled debt restructure or “TDR.” All loans deemed TDR are considered impaired. A loan is considered a TDR when, for economic or legal reasons related to a borrower’s financial difficulties, a concession is granted to the borrower that would not otherwise be considered. Both financial distress on the part of the borrower and the Bank’s granting of a concession, which are detailed further below, must be present in order for the loan to be considered a TDR. All of the following factors are indicators that the debtor is experiencing financial difficulties (one or more items may be present): • The debtor is currently in default on any of its debt. • The debtor has declared or is in the process of declaring bankruptcy. • There is significant doubt as to whether the debtor will continue to be a going concern. • Currently, the debtor has securities being held as collateral that have been delisted, are in the process of being delisted, or are under threat of being delisted from an exchange. • Based on estimates and projections that only encompass the current business capabilities, the debtor forecasts that its entity-specific cash flows will be insufficient to service the debt (both interest and principal) in accordance with the contractual terms of the existing agreement through maturity. • Absent the current modification, the debtor cannot obtain funds from sources other than the existing creditors at an effective interest rate equal to the current market interest rate for similar debt for a non-troubled debtor. The following factors are potential indicators that a concession has been granted (one or multiple items may be present): • The borrower receives a reduction of the stated interest rate for the remaining original life of the debt. • The borrower receives an extension of the maturity date or dates at a stated interest rate lower that the current market interest rate for new debt with similar risk characteristics. • The borrower receives a reduction of the face amount or maturity amount of the debt as stated in the instrument or other agreement. • The borrower receives a deferral of required payments (principal and/or interest). • The borrower receives a reduction of the accrued interest.
Loans and Leases Receivable, Past Due Status, Policy [Policy Text Block]	Non-accrual and Delinquent Loans Loans are placed on non-accrual when (1) payment in full of principal and interest is no longer expected or (2) principal or interest has been in default for 120 days or more (unless there is both a defined source of repayment and it is well secured). All loans rated doubtful or worse, and certain loans rated substandard, are placed on non-accrual. A non-accrual asset may be restored to an accrual status when (1) all past due principal and interest has been paid (excluding renewals and modifications that involve the capitalizing of interest) or (2) the loan becomes well secured with marketable collateral and is in the process of collection. An established track record of performance is also considered when determining accrual status. Delinquency status of a loan is determined by the number of days that have elapsed past the loan’s payment due date, using the following classification groupings: 30-59 days, 60-89 days and 90 days or more.
Subsequent Events, Policy [Policy Text Block]	Management evaluated subsequent events through the date the consolidated financial statements were issued. Events or transactions occurring after December 31, 2016 , but prior to the date the consolidated financial statements were issued, that provided additional evidence about conditions that existed at December 31, 2016 have been recognized in the consolidated financial statements for the period ended December 31, 2016 . Events or transactions that provided evidence about conditions that did not exist at December 31, 2016 , but arose before the consolidated financial statements were issued, have not been recognized in the consolidated financial statements for the period ended December 31, 2016 .

Nature of Business and Signif36

Nature of Business and Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Property, Plant and Equipment [Table Text Block]	Land is carried at cost. Premises and equipment are stated at cost less accumulated depreciation. The estimated useful lives and primary method of depreciation for the principal items are as follows: Years Type of Assets Minimum Maximum Depreciation Method Buildings and leasehold improvements 10 - 30 Straight-line Furniture and equipment 3 - 10 Straight-line
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	The components of accumulated other comprehensive income, included in shareholders’ equity, net of tax, are as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Unrealized gains on securities available for sale, net of tax $ (1,133 ) $ 3,408 $ 5,322 Accumulated other comprehensive income, net of tax $ (1,133 ) $ 3,408 $ 5,322

Business Combination (Tables)

Business Combination (Tables)	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	Estimated fair values of assets acquired and liabilities assumed in the Central transaction, as of the closing date of the transaction, were as follows: (in thousands) May 1, 2015 ASSETS Cash and due from banks $ 28,404 Investment securities 160,775 Loans 916,973 Premises and equipment 27,908 Goodwill 64,654 Core deposit intangible 12,773 Trade name intangible 1,380 FDIC indemnification asset 3,753 Other real estate owned 8,420 Other assets 14,482 Total assets 1,239,522 LIABILITIES Deposits 1,049,167 Short-term borrowings 16,124 Junior subordinated notes issued to capital trusts 8,050 Subordinated notes payable 12,669 Accrued expenses and other liabilities 11,617 Total liabilities 1,097,627 Net assets 141,895 Consideration: Market value of common stock at $29.31 per share at May 1, 2015 (2,723,083 shares of common stock issued), net of stock illiquidity discount due to restrictions 77,895 Cash paid 64,000 Total fair value of consideration $ 141,895
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Table Text Block]	The following table presents the purchased loans as of the acquisition date: (in thousands) Purchased Credit Impaired Loans Purchased Non-Credit Impaired Loans Contractually required principal payments $ 36,886 $ 905,314 Nonaccretable difference (6,675 ) — Principal cash flows expected to be collected 30,211 905,314 Accretable discount (1) (1,882 ) (16,670 ) Fair value of acquired loans $ 28,329 $ 888,644 (1) Included in the accretable discount for Purchased Non-Credit Impaired Loans is approximately $10.4 million of estimated undiscounted principal losses. Changes in accretable yield on the loan pool participations that met the level-yield income recognition criteria under ASC Topic 310 were as follows: Accretable Yield December 31, 2015 (in thousands) Balance at beginning of year $ 1,579 Additions — Accretions (1,579 ) Reclassifications to nonaccretable differences — Balance at end of year $ — Cash flows expected to be collected at acquisition $ — Basis in acquired loans at acquisition $ —
Business Acquisition, Pro Forma Information [Table Text Block]	The following table provides the unaudited pro forma information for the results of operations for the year ended December 31, 2015, as if the acquisition had occurred January 1, 2015. The pro forma results combine the historical results of Central into the Company’s consolidated statement of income including the impact of certain purchase accounting adjustments, including loan discount accretion, investment securities discount accretion, intangible assets amortization, deposit premium accretion and borrowing discount amortization. The pro forma results have been prepared for comparative purposes only and are not necessarily indicative of the results that would have been obtained had the acquisition actually occurred on January 1, 2015. No assumptions have been applied to the pro forma results of operations regarding possible revenue enhancements, expense efficiencies or asset dispositions. Net income in the table below includes merger expenses. Year Ended December 31, (in thousands) 2015 Total revenues (net interest income plus noninterest income) $ 128,613 Net income $ 25,799

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Schedule of Available-for-sale Securities Reconciliation [Table Text Block]	The amortized cost and fair value of investment securities available for sale, with gross unrealized gains and losses, are as follows: Gross Gross Amortized Unrealized Unrealized Estimated Cost Gains Losses Fair Value (in thousands) December 31, 2016 U.S. Government agencies and corporations $ 5,895 $ 10 $ — $ 5,905 State and political subdivisions 162,145 3,545 418 165,272 Mortgage-backed securities 61,606 315 567 61,354 Collateralized mortgage obligations 175,506 148 4,387 171,267 Corporate debt securities 72,979 76 602 72,453 Total debt securities 478,131 4,094 5,974 476,251 Other equity securities 1,259 66 58 1,267 Total investment securities $ 479,390 $ 4,160 $ 6,032 $ 477,518 December 31, 2015 U.S. Treasury securities $ 6,931 $ — $ 21 $ 6,910 U.S. Government agencies and corporations 26,600 99 46 26,653 State and political subdivisions 176,794 6,662 72 183,384 Mortgage-backed securities 56,950 569 457 57,062 Collateralized mortgage obligations 107,613 321 1,530 106,404 Corporate debt securities 45,602 50 86 45,566 Total debt securities 420,490 7,701 2,212 425,979 Other equity securities 1,250 50 38 1,262 Total investment securities $ 421,740 $ 7,751 $ 2,250 $ 427,241
Held-to-maturity Securities [Table Text Block]	The amortized cost and fair value of investment securities held to maturity, with gross unrealized gains and losses, are as follows: Gross Gross Amortized Unrealized Unrealized Estimated Cost Gains Losses Fair Value (in thousands) December 31, 2016 State and political subdivisions $ 107,941 $ 156 $ 2,713 $ 105,384 Mortgage-backed securities 2,398 5 34 2,369 Collateralized mortgage obligations 26,036 — 598 25,438 Corporate debt securities 32,017 149 565 31,601 Total $ 168,392 $ 310 $ 3,910 $ 164,792 December 31, 2015 State and political subdivisions $ 66,454 $ 928 $ 110 $ 67,272 Mortgage-backed securities 3,920 4 38 3,886 Collateralized mortgage obligations 30,505 1 459 30,047 Corporate debt securities 17,544 — 515 17,029 Total $ 118,423 $ 933 $ 1,122 $ 118,234
Schedule of Temporary Impairment Losses, Investments [Table Text Block]	The following tables present information pertaining to securities with gross unrealized losses as of December 31, 2016 and 2015 , aggregated by investment category and length of time that individual securities have been in a continuous loss position: As of December 31, 2016 Number of Securities Less than 12 Months 12 Months or More Total Available for Sale Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands, except number of securities) State and political subdivisions 63 $ 24,574 $ 389 $ 427 $ 29 $ 25,001 $ 418 Mortgage-backed securities 20 40,752 566 23 1 40,775 567 Collateralized mortgage obligations 29 140,698 3,544 16,776 843 157,474 4,387 Corporate debt securities 11 54,891 602 — — 54,891 602 Other equity securities 1 — — 942 58 942 58 Total 124 $ 260,915 $ 5,101 $ 18,168 $ 931 $ 279,083 $ 6,032 As of December 31, 2015 Number of Securities Less than 12 Months 12 Months or More Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands, except number of securities) U.S. Treasury securities 1 $ 6,910 $ 21 $ — $ — $ 6,910 $ 21 U.S. Government agencies and corporations 1 4,890 46 — — 4,890 46 State and political subdivisions 22 8,419 24 3,177 48 11,596 72 Mortgage-backed securities 27 37,753 457 — — 37,753 457 Collateralized mortgage obligations 23 56,447 420 31,253 1,110 87,700 1,530 Corporate debt securities 8 30,496 86 — — 30,496 86 Other equity securities 1 — — 962 38 962 38 Total 83 $ 144,915 $ 1,054 $ 35,392 $ 1,196 $ 180,307 $ 2,250 As of December 31, 2016 Number of Securities Less than 12 Months 12 Months or More Total Held to Maturity Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands, except number of securities) State and political subdivisions 180 $ 65,174 $ 2,713 $ — $ — $ 65,174 $ 2,713 Mortgage-backed securities 5 2,246 34 — — 2,246 34 Collateralized mortgage obligations 7 18,964 369 6,435 229 25,399 598 Corporate debt securities 11 19,198 187 2,512 378 21,710 565 Total 203 $ 105,582 $ 3,303 $ 8,947 $ 607 $ 114,529 $ 3,910 As of December 31, 2015 Number of Securities Less than 12 Months 12 Months or More Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses (in thousands, except number of securities) State and political subdivisions 32 $ 9,345 $ 93 $ 2,040 $ 17 $ 11,385 $ 110 Mortgage-backed securities 5 3,723 38 — — 3,723 38 Collateralized mortgage obligations 7 22,571 320 7,416 139 29,987 459 Corporate debt securities 6 15,606 309 680 206 16,286 515 Total 50 $ 51,245 $ 760 $ 10,136 $ 362 $ 61,381 $ 1,122
Investments Classified by Contractual Maturity Date [Table Text Block]	The contractual maturity distribution of investment debt securities at December 31, 2016 , is summarized as follows: Available For Sale Held to Maturity Amortized Cost Fair Value Amortized Cost Fair Value (in thousands) Due in one year or less $ 11,422 $ 11,468 $ 2,385 $ 2,384 Due after one year through five years 122,263 123,237 9,780 9,700 Due after five years through ten years 95,598 97,246 72,063 71,314 Due after ten years 11,736 11,679 55,730 53,587 Debt securities without a single maturity date 237,112 232,621 28,434 27,807 Total $ 478,131 $ 476,251 $ 168,392 $ 164,792
Schedule of Realized Gain (Loss) [Table Text Block]	Realized gains and losses on sales are determined on the basis of specific identification of investments based on the trade date. Realized gains (losses) on investments, including impairment losses for the years ended December 31, 2016 , 2015 and 2014 , were as follows: Year Ended December 31, 2016 2015 2014 (in thousands) Available for sale fixed maturity securities: Gross realized gains $ 469 $ 1,265 $ 1,463 Gross realized losses (5 ) (442 ) (236 ) 464 823 1,227 Equity securities: Gross realized gains — 188 — Gross realized losses — — — — 188 — Total net realized gains and losses $ 464 $ 1,011 $ 1,227

Loans Receivable and the Allo39

Loans Receivable and the Allowance for Loan Losses (Tables)	12 Months Ended
	Dec. 31, 2016
Loans and Leases Receivable Disclosure [Abstract]
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]	: Allowance for Loan Losses and Recorded Investment in Loan Receivables As of December 31, 2016 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Total Allowance for loan losses: Individually evaluated for impairment $ 62 $ 2,066 $ 1,924 $ 299 $ — $ 4,351 Collectively evaluated for impairment 1,941 4,199 7,692 2,791 255 16,878 Purchased credit impaired loans — 9 244 368 — 621 Total $ 2,003 $ 6,274 $ 9,860 $ 3,458 $ 255 $ 21,850 Loans receivable Individually evaluated for impairment $ 5,339 $ 11,434 $ 11,450 $ 3,955 $ — $ 32,178 Collectively evaluated for impairment 108,004 449,380 1,036,049 480,143 36,591 2,110,167 Purchased credit impaired loans — 156 16,744 5,898 — 22,798 Total $ 113,343 $ 460,970 $ 1,064,243 $ 489,996 $ 36,591 $ 2,165,143 As of December 31, 2015 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Unallocated Total Allowance for loan losses: Individually evaluated for impairment $ 51 $ 489 $ 2,786 $ 387 $ 1 $ — $ 3,714 Collectively evaluated for impairment 1,366 4,962 5,718 3,539 408 (374 ) 15,619 Purchased credit impaired loans — — 52 42 — — 94 Total $ 1,417 $ 5,451 $ 8,556 $ 3,968 $ 409 $ (374 ) $ 19,427 Loans receivable Individually evaluated for impairment $ 3,072 $ 7,718 $ 23,697 $ 5,725 $ 26 $ — $ 40,238 Collectively evaluated for impairment 118,642 461,275 950,207 517,482 38,506 — 2,086,112 Purchased credit impaired loans — 256 18,037 7,299 — — 25,592 Total $ 121,714 $ 469,249 $ 991,941 $ 530,506 $ 38,532 $ — $ 2,151,942
Allowance for Credit Losses on Financing Receivables [Table Text Block]	Allowance for Loan Loss Activity For the Years Ended December 31, 2016, 2015, and 2014 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Unallocated Total 2016 Beginning balance $ 1,417 $ 5,451 $ 8,556 $ 3,968 $ 409 $ (374 ) $ 19,427 Charge-offs (1,204 ) (3,066 ) (931 ) (782 ) (98 ) — (6,081 ) Recoveries 33 124 192 157 15 — 521 Provision 1,757 3,765 2,043 115 (71 ) 374 7,983 Ending balance $ 2,003 $ 6,274 $ 9,860 $ 3,458 $ 255 $ — $ 21,850 2015 Beginning balance $ 1,506 $ 5,780 $ 4,399 $ 3,167 $ 323 $ 1,188 $ 16,363 Charge-offs (245 ) (692 ) (853 ) (740 ) (92 ) — (2,622 ) Recoveries 1 372 7 143 31 — 554 Provision 155 (9 ) 5,003 1,398 147 (1,562 ) 5,132 Ending balance $ 1,417 $ 5,451 $ 8,556 $ 3,968 $ 409 $ (374 ) $ 19,427 2014 Beginning balance $ 1,358 $ 4,980 $ 5,294 $ 3,185 $ 275 $ 1,087 $ 16,179 Charge-offs (26 ) (685 ) (165 ) (409 ) (76 ) — (1,361 ) Recoveries 10 217 61 22 35 — 345 Provision 164 1,268 (791 ) 369 89 101 1,200 Ending balance $ 1,506 $ 5,780 $ 4,399 $ 3,167 $ 323 $ 1,188 $ 16,363
Troubled Debt Restructurings on Financing Receivables [Table Text Block]	The following table sets forth information on the Company's TDRs by class of financing receivable occurring during the stated periods. TDRs may include multiple concessions, and the disclosure classifications in the table are based on the primary concession provided to the borrower. For the Year Ended December 31, 2016 2015 2014 Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment (dollars in thousands) Troubled Debt Restructurings: Agricultural Extended maturity date 1 25 25 0 — — 0 — — Commercial and industrial Extended maturity date 0 — — 0 — — 1 1,405 1,405 Commercial real estate: Commercial real estate-other Other 1 1,000 700 0 — — 0 — — Residential real estate: One- to four- family first liens Interest rate reduction 2 394 394 1 151 151 1 285 292 One- to four- family junior liens Interest rate reduction 1 71 71 0 — — 0 — — Total 5 $ 1,490 $ 1,190 1 $ 151 $ 151 2 $ 1,690 $ 1,697 Loans by class of financing receivable modified as TDRs within the previous 12 months and for which there was a payment default during the stated periods were: For the Year Ended December 31, 2016 2015 2014 Number of Contracts Recorded Investment Number of Contracts Recorded Investment Number of Contracts Recorded Investment (dollars in thousands) Troubled Debt Restructurings That Subsequently Defaulted: Total 0 $ — 0 $ — 0 $ —
Financing Receivable Credit Quality Indicators [Table Text Block]	December 31, 2016 and 2015 : Pass Special Mention/Watch Substandard Doubtful Loss Total (in thousands) 2016 Agricultural $ 95,103 $ 14,089 $ 4,151 $ — $ — $ 113,343 Commercial and industrial 429,392 11,065 19,016 8 — 459,481 Credit cards 1,489 — — — — 1,489 Commercial real estate: Construction & development 121,982 2,732 1,971 — — 126,685 Farmland 83,563 8,986 2,430 — — 94,979 Multifamily 134,975 548 480 — — 136,003 Commercial real estate-other 666,767 20,955 18,854 — — 706,576 Total commercial real estate 1,007,287 33,221 23,735 — — 1,064,243 Residential real estate: One- to four- family first liens 359,029 2,202 11,002 — — 372,233 One- to four- family junior liens 114,233 1,628 1,902 — — 117,763 Total residential real estate 473,262 3,830 12,904 — — 489,996 Consumer 36,419 1 134 37 — 36,591 Total $ 2,042,952 $ 62,206 $ 59,940 $ 45 $ — $ 2,165,143 2015 Agricultural $ 111,361 $ 8,536 $ 1,817 $ — $ — $ 121,714 Commercial and industrial 436,857 12,893 17,652 10 — 467,412 Credit cards 1,354 19 4 — — 1,377 Overdrafts 1,168 100 215 — — 1,483 Commercial real estate: Construction & development 114,640 2,406 3,707 — — 120,753 Farmland 82,442 2,408 4,234 — — 89,084 Multifamily 119,139 371 2,253 — — 121,763 Commercial real estate-other 609,651 19,402 31,288 — — 660,341 Total commercial real estate 925,872 24,587 41,482 — — 991,941 Residential real estate: One- to four- family first liens 410,143 4,813 13,042 235 — 428,233 One- to four- family junior liens 96,223 1,782 4,209 59 — 102,273 Total residential real estate 506,366 6,595 17,251 294 — 530,506 Consumer 37,184 6 278 41 — 37,509 Total $ 2,020,162 $ 52,736 $ 78,699 $ 345 $ — $ 2,151,942
Impaired Financing Receivables [Table Text Block]	December 31, 2016 and 2015 : As of December 31, 2016 2015 Recorded Investment Unpaid Principal Balance Related Allowance Recorded Investment Unpaid Principal Balance Related Allowance (in thousands) With no related allowance recorded: Agricultural $ 3,673 $ 4,952 $ — $ 1,512 $ 2,084 $ — Commercial and industrial 6,211 6,259 — 6,487 6,752 — Credit cards — — — — — — Commercial real estate: Construction & development 445 1,170 — 321 448 — Farmland 2,230 2,380 — 2,711 2,870 — Multifamily — — — 1,632 1,798 — Commercial real estate-other 2,224 2,384 — 12,230 12,642 — Total commercial real estate 4,899 5,934 — 16,894 17,758 — Residential real estate: One- to four- family first liens 2,429 2,442 — 2,494 2,533 — One- to four- family junior liens — — — 1,297 1,308 — Total residential real estate 2,429 2,442 — 3,791 3,841 — Consumer — — — 17 33 — Total $ 17,212 $ 19,587 $ — $ 28,701 $ 30,468 $ — With an allowance recorded: Agricultural $ 1,666 $ 1,669 $ 62 $ 1,560 $ 1,560 $ 51 Commercial and industrial 5,223 5,223 2,066 1,231 1,258 489 Credit cards — — — — — — Commercial real estate: Construction & development 263 270 21 34 34 34 Farmland — — — 69 69 3 Multifamily — — — 224 224 73 Commercial real estate-other 6,288 6,344 1,903 6,476 6,478 2,676 Total commercial real estate 6,551 6,614 1,924 6,803 6,805 2,786 Residential real estate: One- to four- family first liens 1,526 1,526 299 1,919 2,056 383 One- to four- family junior liens — — — 15 15 4 Total residential real estate 1,526 1,526 299 1,934 2,071 387 Consumer — — — 9 9 1 Total $ 14,966 $ 15,032 $ 4,351 $ 11,537 $ 11,703 $ 3,714 Total: Agricultural $ 5,339 $ 6,621 $ 62 $ 3,072 $ 3,644 $ 51 Commercial and industrial 11,434 11,482 2,066 7,718 8,010 489 Credit cards — — — — — — Commercial real estate: Construction & development 708 1,440 21 355 482 34 Farmland 2,230 2,380 — 2,780 2,939 3 Multifamily — — — 1,856 2,022 73 Commercial real estate-other 8,512 8,728 1,903 18,706 19,120 2,676 Total commercial real estate 11,450 12,548 1,924 23,697 24,563 2,786 Residential real estate: One- to four- family first liens 3,955 3,968 299 4,413 4,589 383 One- to four- family junior liens — — — 1,312 1,323 4 Total residential real estate 3,955 3,968 299 5,725 5,912 387 Consumer — — — 26 42 1 Total $ 32,178 $ 34,619 $ 4,351 $ 40,238 $ 42,171 $ 3,714 The following table presents the average recorded investment and interest income recognized for loans individually evaluated for impairment, excluding purchased credit impaired loans, by class of loan, during the stated periods: For the Year Ended December 31, 2016 2015 2014 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized (in thousands) With no related allowance recorded: Agricultural $ 3,815 $ 88 $ 1,533 $ 58 $ 1,413 $ 211 Commercial and industrial 6,540 79 6,769 424 2,234 160 Credit cards — — — — — — Commercial real estate: Construction & development 390 54 325 7 49 — Farmland 2,389 97 2,743 128 2,288 456 Multifamily — — 1,833 68 — — Commercial real estate-other 2,243 60 12,772 446 975 — Total commercial real estate 5,022 211 17,673 649 3,312 456 Residential real estate: One- to four- family first liens 2,430 101 2,469 81 547 32 One- to four- family junior liens — — 1,313 42 134 6 Total residential real estate 2,430 101 3,782 123 681 38 Consumer — — 21 2 8 — Total $ 17,807 $ 479 $ 29,778 $ 1,256 $ 7,648 $ 865 With an allowance recorded: Agricultural $ 1,678 $ 46 $ 1,572 $ 48 $ 1,627 $ 203 Commercial and industrial 5,277 74 1,313 67 1,044 104 Credit cards — — — — — — Commercial real estate: Construction & development 263 3 34 — 35 3 Farmland — — 70 2 74 3 Multifamily — — 226 6 — — Commercial real estate-other 6,515 — 6,528 344 551 43 Total commercial real estate 6,778 3 6,858 352 660 49 Residential real estate: One- to four- family first liens 1,559 41 1,928 44 2,612 203 One- to four- family junior liens — — 15 — 74 — Total residential real estate 1,559 41 1,943 44 2,686 203 Consumer — — 9 — 31 5 Total $ 15,292 $ 164 $ 11,695 $ 511 $ 6,048 $ 564 Total: Agricultural $ 5,493 $ 134 $ 3,105 $ 106 $ 3,040 $ 414 Commercial and industrial 11,817 153 8,082 491 3,278 264 Credit cards — — — — — — Commercial real estate: Construction & development 653 57 359 7 84 3 Farmland 2,389 97 2,813 130 2,362 459 Multifamily — — 2,059 74 — — Commercial real estate-other 8,758 60 19,300 790 1,526 43 Total commercial real estate 11,800 214 24,531 1,001 3,972 505 Residential real estate: One- to four- family first liens 3,989 142 4,397 125 3,159 235 One- to four- family junior liens — — 1,328 42 208 6 Total residential real estate 3,989 142 5,725 167 3,367 241 Consumer — — 30 2 39 5 Total $ 33,099 $ 643 $ 41,473 $ 1,767 $ 13,696 $ 1,429
Past Due Loan Receivables [Table Text Block]	December 31, 2016 and 2015 : 30 - 59 Days Past Due 60 - 89 Days Past Due 90 Days or More Past Due Total Past Due Current Total Loans Receivable (in thousands) 2016 Agricultural $ 44 $ — $ 399 $ 443 $ 112,900 $ 113,343 Commercial and industrial 2,615 293 9,654 12,562 446,919 459,481 Credit cards — — — — 1,489 1,489 Commercial real estate: Construction & development 630 — 297 927 125,758 126,685 Farmland 373 — 91 464 94,515 94,979 Multifamily — 129 — 129 135,874 136,003 Commercial real estate-other 1,238 763 6,655 8,656 697,920 706,576 Total commercial real estate 2,241 892 7,043 10,176 1,054,067 1,064,243 Residential real estate: One- to four- family first liens 2,851 1,143 1,328 5,322 366,911 372,233 One- to four- family junior liens 437 151 150 738 117,025 117,763 Total residential real estate 3,288 1,294 1,478 6,060 483,936 489,996 Consumer 50 23 33 106 36,485 36,591 Total $ 8,238 $ 2,502 $ 18,607 $ 29,347 $ 2,135,796 $ 2,165,143 Included in the totals above are the following purchased credit impaired loans $ 965 $ 489 $ 549 $ 2,003 $ 20,795 $ 22,798 2015 Agricultural $ 19 $ 190 $ 169 $ 378 $ 121,336 $ 121,714 Commercial and industrial 1,046 710 644 2,400 465,012 467,412 Credit cards 2 17 4 23 1,354 1,377 Overdrafts 175 8 31 214 1,269 1,483 Commercial real estate: Construction & development — — 415 415 120,338 120,753 Farmland 120 — 80 200 88,884 89,084 Multifamily — — 224 224 121,539 121,763 Commercial real estate-other 1,190 754 1,636 3,580 656,761 660,341 Total commercial real estate 1,310 754 2,355 4,419 987,522 991,941 Residential real estate: One- to four- family first liens 2,611 1,293 1,772 5,676 422,557 428,233 One- to four- family junior liens 168 120 317 605 101,668 102,273 Total residential real estate 2,779 1,413 2,089 6,281 524,225 530,506 Consumer 62 6 17 85 37,424 37,509 Total $ 5,393 $ 3,098 $ 5,309 $ 13,800 $ 2,138,142 $ 2,151,942 Included in the totals above are the following purchased credit impaired loans 473 799 989 2,261 23,331 25,592
Schedule of Financing Receivables, Non Accrual Status [Table Text Block]	December 31, 2016 and 2015 : As of December 31, 2016 2015 Non-Accrual Loans Past Due 90 Days or More and Still Accruing Non-Accrual Loans Past Due 90 Days or More and Still Accruing (in thousands) Agricultural $ 2,690 $ — $ 172 $ — Commercial and industrial 8,358 — 575 — Credit cards — — — — Commercial real estate: Construction & development 780 95 95 — Farmland 227 — 20 80 Multifamily — — 224 — Commercial real estate-other 7,360 — 1,452 — Total commercial real estate 8,367 95 1,791 80 Residential real estate: One- to four- family first liens 1,127 375 1,182 199 One- to four- family junior liens 116 15 281 — Total residential real estate 1,243 390 1,463 199 Consumer 10 — 11 5 Total $ 20,668 $ 485 $ 4,012 $ 284
Schedule of Changes in Accretable Yield for Purchased Credit Impaired Loans [Table Text Block]	Changes in the accretable yield for loans acquired and accounted for under ASC 310-30 were as follows for the year ended December 31, 2016 and 2015 : For the Year Ended December 31, 2016 2015 (in thousands) Balance at beginning of period $ 1,446 $ — Purchases — 1,882 Accretion (3,287 ) (666 ) Reclassification from nonaccretable difference (1) 3,802 230 Balance at end of period $ 1,961 $ 1,446
Loan Pool Participations [Table Text Block]	A summary of the changes in the carrying value of loan pool participations for the year ended December 31, 2015 , is as follows: For the Year Ended December 31, 2015 (in thousands) Balance at beginning of year $ 19,332 Principal payments and sale proceeds (18,823 ) Net charge-offs (509 ) Balance at end of year $ — Total face value at end of year $ —
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Table Text Block]	The following table presents the purchased loans as of the acquisition date: (in thousands) Purchased Credit Impaired Loans Purchased Non-Credit Impaired Loans Contractually required principal payments $ 36,886 $ 905,314 Nonaccretable difference (6,675 ) — Principal cash flows expected to be collected 30,211 905,314 Accretable discount (1) (1,882 ) (16,670 ) Fair value of acquired loans $ 28,329 $ 888,644 (1) Included in the accretable discount for Purchased Non-Credit Impaired Loans is approximately $10.4 million of estimated undiscounted principal losses. Changes in accretable yield on the loan pool participations that met the level-yield income recognition criteria under ASC Topic 310 were as follows: Accretable Yield December 31, 2015 (in thousands) Balance at beginning of year $ 1,579 Additions — Accretions (1,579 ) Reclassifications to nonaccretable differences — Balance at end of year $ — Cash flows expected to be collected at acquisition $ — Basis in acquired loans at acquisition $ —

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment [Table Text Block]	Premises and equipment as of December 31, 2016 and 2015 were as follows: As of December 31, 2016 2015 (in thousands) Land $ 12,970 $ 13,270 Buildings and leasehold improvements 68,405 60,871 Furniture and equipment 15,851 17,160 Construction in process 1,439 10,972 Premises and equipment 98,665 102,273 Accumulated depreciation and amortization 23,622 26,071 Premises and equipment, net $ 75,043 $ 76,202

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Goodwill [Table Text Block]	The following table presents the changes in the carrying amount of intangibles (excluding goodwill), gross carrying amount, accumulated amortization, net book value, and weighted average life as of December 31, 2016 and 2015 : Insurance Agency Intangible Core Deposit Intangible Indefinite-Lived Trade Name Intangible Finite-Lived Trade Name Intangible Customer List Intangible Total (dollars in thousands) December 31, 2016 Balance, beginning of period $ 275 $ 10,480 $ 7,040 $ 1,203 $ 143 $ 19,141 Amortization expense (72 ) (3,634 ) — (243 ) (21 ) (3,970 ) Balance at end of period $ 203 $ 6,846 $ 7,040 $ 960 $ 122 $ 15,171 Gross carrying amount $ 1,320 $ 18,206 $ 7,040 $ 1,380 $ 330 $ 28,276 Accumulated amortization (1,117 ) (11,360 ) — (420 ) (208 ) (13,105 ) Net book value $ 203 $ 6,846 $ 7,040 $ 960 $ 122 $ 15,171 Remaining weighted average useful life (years) 7 5 8 7 Insurance Agency Intangible Core Deposit Intangible Indefinite-Lived Trade Name Intangible Finite-Lived Trade Name Intangible Customer List Intangible Total (dollars in thousands) December 31, 2015 Balance, beginning of period $ 364 $ 691 $ 7,040 $ — $ 164 $ 8,259 Additions from business combination — 12,773 — 1,380 — 14,153 Amortization expense (89 ) (2,984 ) — (177 ) (21 ) (3,271 ) Balance at end of period $ 275 $ 10,480 $ 7,040 $ 1,203 $ 143 $ 19,141 Gross carrying amount $ 1,320 $ 18,206 $ 7,040 $ 1,380 $ 330 $ 28,276 Accumulated amortizations (1,045 ) (7,726 ) — (177 ) (187 ) (9,135 ) Net book value $ 275 $ 10,480 $ 7,040 $ 1,203 $ 143 $ 19,141 Remaining weighted average useful life (years) 7 6 9 8
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	The following table summarizes future amortization expense of intangible assets: Insurance Core Trade Customer Agency Deposit Name List Intangible Premium Intangible Intangible Totals (in thousands) Year ending December 31, 2017 $ 55 $ 2,835 $ 216 $ 19 $ 3,125 2018 38 2,037 188 18 2,281 2019 21 1,312 161 17 1,511 2020 20 613 133 16 782 2021 19 49 106 15 189 Thereafter 50 — 156 37 243 Total $ 203 $ 6,846 $ 960 $ 122 $ 8,131

Other Assets (Tables)

Other Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Other Assets [Abstract]
Schedule of Other Assets [Table Text Block]	The components of the Company’s other assets as of December 31, 2016 and 2015 were as follows: As of December 31, 2016 2015 (in thousands) Federal Home Loan Bank Stock $ 12,800 $ 9,832 FDIC indemnification asset, net 479 4,274 Prepaid expenses 1,760 2,271 Mortgage servicing rights 1,951 2,249 Federal and state taxes, current — 1,079 Accounts receivable & other miscellaneous assets 1,323 2,104 $ 18,313 $ 21,809

Time Deposits (Tables)

Time Deposits (Tables)	12 Months Ended
	Dec. 31, 2016
Deposits [Abstract]
Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block]	At December 31, 2016 , the scheduled maturities of certificates of deposits were as follows: (in thousands) 2017 $ 402,316 2018 100,028 2019 81,325 2020 27,050 2021 40,410 Thereafter 753 Total $ 651,882

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2016
Short-term Debt [Abstract]
Schedule of Short-term Debt [Table Text Block]	Short-term borrowings were as follows as of December 31, 2016 and December 31, 2015 : December 31, 2016 December 31, 2015 (dollars in thousands) Weighted Average Cost Balance Weighted Average Cost Balance Federal funds purchased 0.83 35,684 0.34 1,500 Securities sold under agreements to repurchase 0.22 82,187 0.31 67,463 Total 0.40 % $ 117,871 0.31 % $ 68,963

Subordinated Notes Payable (Tab

Subordinated Notes Payable (Tables)	12 Months Ended
	Dec. 31, 2016
Junior Subordinated Notes [Abstract]
Schedule of Subordinated Borrowing [Table Text Block]	The table below summarizes the outstanding junior subordinated notes and the related trust preferred securities issued by each trust as of as of December 31, 2016 and December 31, 2015 : Face Value Book Value Interest Rate Year-end Interest Rate Maturity Date Callable Date (in thousands) 2016 Central Bancshares Capital Trust II (1) (2) $ 7,217 $ 6,614 Three-month LIBOR + 3.50% 4.46 % 03/15/2038 03/15/2013 Barron Investment Capital Trust I (1) (2) 2,062 1,614 Three-month LIBOR + 2.15% 3.15 % 09/23/2036 09/23/2011 MidWestOne Statutory Trust II (1) 15,464 15,464 Three-month LIBOR + 1.59% 2.55 % 12/15/2037 12/15/2012 Total $ 24,743 $ 23,692 2015 Central Bancshares Capital Trust II (1) (2) $ 7,217 $ 6,552 Three-month LIBOR + 3.50% 4.01 % 3/15/2038 3/15/2013 Barron Investment Capital Trust I (1) (2) 2,062 1,571 Three-month LIBOR + 2.15% 2.74 % 9/23/2036 9/23/2011 MidWestOne Statutory Trust II (1) 15,464 15,464 Three-month LIBOR + 1.59% 2.10 % 12/15/2037 12/15/2012 Total $ 24,743 $ 23,587 (1) All distributions are cumulative and paid in cash quarterly. (2) Central Bancshares Capital Trust II was established by Central and Barron Investment Capital Trust I was acquired by Central, prior to the Company’s merger with Central, and the obligations under the junior subordinated notes issued by Central to these trusts were assumed by the Company.

Long-Term Borrowings (Tables)

Long-Term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2016
Long-term Debt, by Type, Current and Noncurrent [Abstract]
Schedule of Long-term Debt Instruments [Table Text Block]	Long-term borrowings were as follows as of December 31, 2016 and December 31, 2015 : December 31, 2016 December 31, 2015 (dollars in thousands) Weighted Average Cost Balance Weighted Average Cost Balance FHLB Borrowings 1.56 % $ 115,000 1.64 % $ 87,000 Note payable to unaffiliated bank 2.52 17,500 2.17 22,500 Total 1.69 % $ 132,500 1.75 % $ 109,500
Schedule of Federal Home Loan Bank, Advances, by Branch of FHLB Bank [Table Text Block]	As of December 31, 2016 and 2015 , FHLB borrowings were as follows: Rates Amount Minimum Maximum 2016 2015 (dollars in thousands) Due in 2016 0.50 % to 2.46 % $ — $ 22,000 Due in 2017 0.79 % to 2.78 % 30,000 10,000 Due in 2018 1.30 % to 1.60 % 19,000 19,000 Due in 2019 1.42 % to 1.85 % 27,000 17,000 Due in 2020 1.52 % to 2.25 % 32,000 12,000 Due in 2021 1.93 % to 1.93 % 7,000 7,000 Total $ 115,000 $ 87,000

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	Income taxes for the years ended December 31, 2016 , 2015 and 2014 are summarized as follows: December 31, 2016 2015 2014 (in thousands) Current: Federal $ 7,410 $ 6,147 $ 3,573 State 2,303 372 956 Deferred (2,853 ) 1,300 2,502 Total income tax provision $ 6,860 $ 7,819 $ 7,031
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	The income tax provisions for the years ended December 31, 2016 , 2015 and 2014 were less than the amounts computed by applying the maximum effective federal income tax rate of 35% for the years ended December 31, 2016 , 2015 , and 2014 , to the income before income taxes because of the following items: 2016 2015 2014 (dollars in thousands) Amount % of Pretax Income Amount % of Pretax Income Amount % of Pretax Income Expected provision $ 9,538 35.0 % $ 11,528 35.0 % $ 8,943 35.0 % Tax-exempt interest (3,011 ) (11.0 ) (2,817 ) (8.6 ) (2,520 ) (9.9 ) Bank-owned life insurance (477 ) (1.8 ) (438 ) (1.3 ) (385 ) (1.5 ) State income taxes, net of federal income tax benefit 1,257 4.6 333 1.0 798 3.1 Non-deductible acquisition expenses 83 0.3 691 2.1 261 1.0 General business credits (537 ) (2.0 ) (1,225 ) (3.7 ) — — Other 7 0.1 (253 ) (0.8 ) (66 ) (0.3 ) Total income tax provision $ 6,860 25.2 % $ 7,819 23.7 % $ 7,031 27.4 %
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	Net deferred tax assets as of December 31, 2016 and 2015 consisted of the following components: December 31, 2016 2015 (in thousands) Deferred income tax assets: Allowance for loan losses $ 8,585 $ 7,449 Deferred compensation 1,982 1,909 Net operating losses (state net operating loss carryforwards) 3,838 3,560 Unrealized losses on investment securities 738 — Other real estate owned 283 146 Other 3,012 1,934 Gross deferred tax assets 18,438 14,998 Deferred income tax liabilities: Premises and equipment depreciation and amortization 4,092 3,658 Federal Home Loan Bank stock 137 133 Purchase accounting adjustments 2,352 2,717 Mortgage servicing rights 766 853 Prepaid expenses 289 194 Unrealized gains on investment securities — 2,091 Deferred loan fees 225 261 Other 216 584 Gross deferred tax liabilities 8,077 10,491 Net deferred income tax asset 10,361 4,507 Valuation allowance 3,838 3,560 Net deferred tax asset $ 6,523 $ 947

Stock Compensation Plans (Table

Stock Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]	The following is a summary of stock option activity for the year ended December 31, 2016 : Weighted- Average Weighted- Remaining Aggregate Average Contractual Intrinsic Exercise Term in Value Shares Price Years ($000) Outstanding at December 31, 2015 22,300 $ 13.51 Granted — — Exercised (2,900 ) 18.25 Forfeited — — Expired (950 ) 20.08 Outstanding at December 31, 2016 18,450 $ 12.42 1.76 $ 465 Exercisable at December 31, 2016 18,450 $ 12.42 1.76 $ 465
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]	The following is a summary of nonvested restricted stock unit activity for the year ended December 31, 2016 : Weighted- Average Grant-Date Shares Fair Value Nonvested at December 31, 2015 60,858 $ 26.46 Granted 38,200 27.03 Vested (26,133 ) 25.47 Forfeited (6,875 ) 27.85 Nonvested at December 31, 2016 66,050 $ 27.04

Earnings per Share (Tables)

Earnings per Share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	Following are the calculations for basic and diluted earnings per common share: Year Ended December 31, 2016 2015 2014 (dollars in thousands, except per share amounts) Basic earnings per common share computation Numerator: Net income $ 20,391 $ 25,118 $ 18,522 Denominator: Weighted average shares outstanding 11,430,087 10,362,929 8,405,284 Basic earnings per common share $ 1.78 $ 2.42 $ 2.20 Diluted earnings per common share computation Numerator: Net income $ 20,391 $ 25,118 $ 18,522 Denominator: Weighted average shares outstanding, included all dilutive potential shares 11,456,324 10,391,323 8,433,296 Diluted earnings per common share $ 1.78 $ 2.42 $ 2.19

Regulatory Capital Requiremen50

Regulatory Capital Requirements and Restrictions on Subsidiary Cash (Tables)	12 Months Ended
	Dec. 31, 2016
Regulatory Capital Requirements [Abstract]
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block]	A comparison of the Company’s and the Banks’ capital with the corresponding minimum regulatory requirements in effect as of December 31, 2016 and December 31, 2015 , is presented below: Actual For Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio (dollars in thousands) At December 31, 2016: Consolidated: Total capital/risk weighted assets $ 280,396 11.65 % $ 207,661 8.625 % N/A N/A Tier 1 capital/risk weighted assets 258,304 10.73 159,508 6.625 N/A N/A Common equity tier 1 capital/risk weighted assets 234,638 9.75 123,393 5.125 N/A N/A Tier 1 leverage capital/average assets 258,304 8.75 118,040 4.000 N/A N/A MidWest One Bank: Total capital/risk weighted assets $ 286,959 11.96 % $ 206,892 8.625 % $ 239,875 10.00 % Tier 1 capital/risk weighted assets 264,871 11.04 158,917 6.625 191,900 8.00 Common equity tier 1 capital/risk weighted assets 264,871 11.04 122,936 5.125 155,919 6.50 Tier 1 leverage capital/average assets 264,871 8.98 118,000 4.000 147,500 5.00 At December 31, 2015: Consolidated: Total capital/risk weighted assets $ 263,717 11.48 % $ 183,718 8.00 % N/A N/A Tier 1 capital/risk weighted assets 244,154 10.63 137,789 6.00 N/A N/A Common equity tier 1 capital/risk weighted assets 220,567 9.60 103,342 4.50 N/A N/A Tier 1 leverage capital/average assets 244,154 8.34 117,123 4.00 N/A N/A MidWest One Bank: Total capital/risk weighted assets $ 171,583 12.53 % $ 109,578 8.00 % $ 136,972 10.00 % Tier 1 capital/risk weighted assets 154,726 11.30 82,183 6.00 109,578 8.00 Common equity tier 1 capital/risk weighted assets 154,726 11.30 61,638 4.50 89,032 6.50 Tier 1 leverage capital/average assets 154,726 8.90 69,501 4.00 86,876 5.00 Central Bank Total capital/risk weighted assets $ 102,718 11.14 % $ 73,792 8.00 % $ 92,240 10.00 % Tier 1 capital/risk weighted assets 100,017 10.84 55,344 6.00 73,792 8.00 Common equity tier 1 capital/risk weighted assets 100,017 10.84 41,508 4.50 59,956 6.50 Tier 1 leverage capital/average assets 100,017 8.44 47,412 4.00 59,265 5.00

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Credit Commitments [Table Text Block]	A summary of the Bank’s commitments at December 31, 2016 and 2015 , is as follows: December 31, 2016 2015 (in thousands) Commitments to extend credit $ 473,725 $ 417,927 Commitments to sell loans 4,241 3,187 Standby letters of credit 9,320 16,146 Total $ 487,286 $ 437,260

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Schedule of Related Party Transactions [Table Text Block]	The following is an analysis of the changes in the loans to related parties during the years ended December 31, 2016 and 2015 : Year Ended December 31, 2016 2015 (in thousands) Balance, beginning $ 10,247 $ 11,655 Net decrease due to change in related parties (906 ) (284 ) Advances 2,834 3,919 Collections (1,319 ) (5,043 ) Balance, ending $ 10,856 $ 10,247

Estimated Fair Value of Finan53

Estimated Fair Value of Financial Instruments and Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The following table summarizes assets measured at fair value on a recurring basis as of December 31, 2016 and 2015 . There were no liabilities subject to fair value measurement on a recurring basis as of these dates. The assets are segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value: Fair Value Measurement at December 31, 2016 Using (in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Significant Unobservable Inputs (Level 3) Assets: Available for sale debt securities: U.S. Government agencies and corporations $ 5,905 $ — $ 5,905 $ — State and political subdivisions 165,272 — 165,272 — Mortgage-backed securities 61,354 — 61,354 — Collateralized mortgage obligations 171,267 — 171,267 — Corporate debt securities 72,453 — 72,453 — Total available for sale debt securities 476,251 — 476,251 — Other equity securities 1,267 1,267 — — Total securities available for sale $ 477,518 $ 1,267 $ 476,251 $ — Fair Value Measurement at December 31, 2015 Using (in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Available for sale debt securities: U.S. Treasury securities $ 6,910 $ — $ 6,910 $ — U.S. Government agencies and corporations 26,653 — 26,653 — State and political subdivisions 183,384 — 183,384 — Mortgage-backed securities 57,062 — 57,062 — Collateralized mortgage obligations 106,404 — 106,404 — Corporate debt securities 45,566 — 45,566 — Total available for sale debt securities 425,979 — 425,979 — Other equity securities 1,262 1,262 — — Total securities available for sale $ 427,241 $ 1,262 $ 425,979 $ —
Fair Value Measurements, Nonrecurring [Table Text Block]	The following table discloses the Company’s estimated fair value amounts of its assets recorded at fair value on a nonrecurring basis. It is management’s belief that the fair values presented below are reasonable based on the valuation techniques and data available to the Company as of December 31, 2016 and 2015 , as more fully described above. Fair Value Measurement at December 31, 2016 Using (in thousands) Total Quoted Prices in Significant Other Significant Unobservable Inputs (Level 3) Assets: Collateral dependent impaired loans $ 8,774 $ — $ — $ 8,774 Other real estate owned $ 2,097 $ — $ — $ 2,097 Fair Value Measurement at December 31, 2015 Using (in thousands) Total Quoted Prices in Significant Other Significant Assets: Collateral dependent impaired loans $ 23,812 $ — $ — $ 23,812 Other real estate owned $ 8,834 $ — $ — $ 8,834
Fair Value, by Balance Sheet Grouping [Table Text Block]	The following presents the carrying amount and estimated fair value of the financial instruments held by the Company at December 31, 2016 and 2015 . The information presented is subject to change over time based on a variety of factors. The operations of the Company are managed on a going concern basis and not a liquidation basis. As a result, the ultimate value realized from the financial instruments presented could be substantially different when actually recognized over time through the normal course of operations. Additionally, a substantial portion of the Company’s inherent value is the capitalization and franchise value of the Bank. Neither of these components has been given consideration in the presentation of fair values below. December 31, 2016 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Financial assets: Cash and cash equivalents $ 43,228 $ 43,228 $ 43,228 $ — $ — Investment securities: Available for sale 477,518 477,518 1,267 476,251 — Held to maturity 168,392 164,792 — 164,792 — Total investment securities 645,910 642,310 1,267 641,043 — Loans held for sale 4,241 4,286 — — 4,286 Loans, net 2,143,293 2,138,252 — 2,138,252 — Accrued interest receivable 13,871 13,871 13,871 — — Federal Home Loan Bank stock 12,800 12,800 — 12,800 — Financial liabilities: Deposits: Non-interest-bearing demand 494,586 494,586 494,586 — — Interest-bearing checking 1,136,282 1,136,282 1,136,282 — — Savings 197,698 197,698 197,698 — — Certificates of deposit under $100,000 326,832 324,978 — 324,978 — Certificates of deposit $100,000 and over 325,050 324,060 — 324,060 — Total deposits 2,480,448 2,477,604 1,828,566 649,038 — Federal funds purchased and securities sold under agreements to repurchase 117,871 117,871 117,871 — — Federal Home Loan Bank borrowings 115,000 114,590 — 114,590 — Junior subordinated notes issued to capital trusts 23,692 19,248 — 19,248 — Long-term debt 17,500 17,500 — 17,500 — Accrued interest payable 1,472 1,472 1,472 — — December 31, 2015 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Financial assets: Cash and cash equivalents $ 47,097 $ 47,097 $ 47,097 $ — $ — Investment securities: Available for sale 427,241 427,241 1,262 425,979 — Held to maturity 118,423 118,234 — 118,234 — Total investment securities 545,664 545,475 1,262 544,213 — Loans held for sale 3,187 3,262 — — 3,262 Loans, net 2,132,515 2,132,009 — 2,132,009 — Accrued interest receivable 13,736 13,736 13,736 — — Federal Home Loan Bank stock 9,832 9,832 — 9,832 — Financial liabilities: Deposits: Non-interest bearing demand 559,586 559,586 559,586 — — Interest-bearing checking 1,064,350 1,064,350 1,064,350 — — Savings 189,489 189,489 189,489 — — Certificates of deposit under $100,000 348,268 346,875 — 346,875 — Certificates of deposit $100,000 and over 301,828 301,521 — 301,521 — Total deposits 2,463,521 2,461,821 1,813,425 648,396 — Federal funds purchased and securities sold under agreements to repurchase 68,963 68,963 68,963 — — Federal Home Loan Bank borrowings 87,000 86,817 — 86,817 — Junior subordinated notes issued to capital trusts 23,587 18,611 — 18,611 — Long-term debt 22,500 22,500 — 22,500 — Accrued interest payable 1,507 1,507 1,507 — —
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Table Text Block]	The following presents the valuation technique(s), observable inputs, and quantitative information about the unobservable inputs used for fair value measurements of the financial instruments held by the Company at December 31, 2016 , categorized within Level 3 of the fair value hierarchy: Quantitative Information About Level 3 Fair Value Measurements (dollars in thousands) Fair Value at December 31, 2016 Valuation Techniques(s) Unobservable Input Range of Inputs Weighted Average Collateral dependent impaired loans $ 8,774 Modified appraised value Third party appraisal NM * NM * NM * Appraisal discount NM * NM * NM * Other real estate owned $ 2,097 Modified appraised value Third party appraisal NM * NM * NM * Appraisal discount NM * NM * NM * * Not Meaningful. Third party appraisals are obtained as to the value of the underlying asset, but disclosure of this information would not provide meaningful information, as the range will vary widely from loan to loan. Types of discounts considered include age of the appraisal, local market conditions, current condition of the property, and estimated sales costs. These discounts will also vary from loan to loan, thus providing a range would not be meaningful.

Parent Company Only Financial54

Parent Company Only Financial Information (Tables)	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Schedule of Condensed Balance Sheet [Table Text Block]	The following is condensed financial information of MidWest One Financial Group, Inc. as of December 31, 2016 and 2015 (parent company only): As of December 31, 2016 2015 (in thousands) Balance Sheets Assets Cash $ 2,621 $ 4,489 Investment in subsidiaries 336,937 331,612 Investment securities available for sale 326 300 Investment securities held to maturity 743 743 Income tax receivable 1,479 571 Other assets 4,947 4,976 Total assets $ 347,053 $ 342,691 Liabilities and Shareholders’ Equity Liabilities: Junior subordinated notes issued to capital trusts $ 23,692 $ 23,587 Long-term debt 17,500 22,500 Deferred income taxes 84 113 Other liabilities 321 313 Total liabilities 41,597 46,513 Shareholders’ equity: Capital stock, preferred — — Capital stock, common 11,713 11,713 Additional paid-in capital 163,667 163,487 Treasury stock (5,766 ) (6,331 ) Retained earnings 136,975 123,901 Accumulated other comprehensive income (1,133 ) 3,408 Total shareholders’ equity 305,456 296,178 Total liabilities and shareholders’ equity $ 347,053 $ 342,691
Schedule of Condensed Income Statement [Table Text Block]	The following is condensed financial information of MidWest One Financial Group, Inc.for the years ended December 31, 2016 , 2015 , and 2014 (parent company only): Year Ended December 31, 2016 2015 2014 (in thousands) Statements of Income Dividends received from subsidiaries $ 12,508 $ 53,511 $ 8,500 Interest income and dividends on investment securities 31 30 49 Interest and discount on loan pool participations — (69 ) (293 ) Investment securities gains — 188 — Loss on sale of loan pool participations — (455 ) — Interest on debt (1,305 ) (1,135 ) (281 ) Operating expenses (1,966 ) (5,233 ) (2,351 ) Income before income taxes and equity in subsidiaries’ undistributed income 9,268 46,837 5,624 Income tax benefit (1,245 ) (1,951 ) (807 ) Income before equity in subsidiaries’ undistributed income 10,513 48,788 6,431 Equity in subsidiaries’ undistributed income 9,878 (23,670 ) 12,091 Net income $ 20,391 $ 25,118 $ 18,522
Schedule of Condensed Cash Flow Statement [Table Text Block]	The following is condensed financial information of MidWest One Financial Group, Inc. for the years ended December 31, 2016 , 2015 , and 2014 (parent company only): Year Ended December 31, 2016 2015 2014 (in thousands) Statements of Cash Flows Cash flows from operating activities: Net income $ 20,391 $ 25,118 $ 18,522 Adjustments to reconcile net income to net cash provided by operating activities: Undistributed (earnings) loss of subsidiaries, net of dividends and distributions (9,878 ) 23,670 (12,091 ) Amortization of premium on junior subordinated notes issued to capital trusts 105 73 — Deferred income taxes (35 ) 617 330 Investment securities gain — (188 ) — Stock based compensation 731 634 493 (Increase) decrease in other assets (879 ) 518 (488 ) Increase (decrease) in other liabilities 8 (907 ) 550 Net cash provided by operating activities 10,443 49,535 7,316 Cash flows from investing activities Proceeds from sales of available for sale securities 1 1,173 2 Purchase of available for sale securities (9 ) (14 ) (29 ) Proceeds from maturities and calls of held to maturity securities — 246 — Loan participation pools, net — 1,964 1,445 Net cash acquired in business combination — (62,902 ) — Investment in subsidiary - Central Bank — (3,000 ) — Net cash provided by (used in) investing activities (8 ) (62,533 ) 1,418 Cash flows from financing activities: Stock options exercised 14 158 282 Repurchase of common stock — — (3,987 ) Redemption of subordinated note payable — (12,669 ) — Proceeds from long-term debt — 25,000 — Payments on long-term debt (5,000 ) (2,500 ) — Issuance of common stock, net of expenses — 7,900 — Dividends paid (7,317 ) (6,344 ) (4,868 ) Net cash provided by (used in) financing activities (12,303 ) 11,545 (8,573 ) Increase (decrease) in cash (1,868 ) (1,453 ) 161 Cash Balance: Beginning 4,489 5,942 5,781 Ending $ 2,621 $ 4,489 $ 5,942

Quarterly Results of Operatio55

Quarterly Results of Operations (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information [Table Text Block]	Three Months Ended December 31 September 30 June 30 March 31 (in thousands, except per share amounts) 2016 Interest income $ 27,914 $ 27,891 $ 28,038 $ 28,485 Interest expense 3,384 3,310 3,098 2,930 Net interest income 24,530 24,581 24,940 25,555 Provision for loan losses 4,742 1,005 1,171 1,065 Noninterest income 5,720 5,714 5,595 6,405 Noninterest expense 21,106 20,439 22,815 23,446 Income before income taxes 4,402 8,851 6,549 7,449 Income tax expense 532 2,629 1,794 1,905 Net income $ 3,870 $ 6,222 $ 4,755 $ 5,544 Net income per common share - basic $ 0.34 $ 0.54 $ 0.42 $ 0.49 Net income per common share - diluted $ 0.34 $ 0.54 $ 0.42 $ 0.48 2015 Interest income $ 29,044 $ 29,989 $ 25,185 $ 16,482 Interest expense 2,716 3,230 2,462 2,240 Net interest income 26,328 26,759 22,723 14,242 Provision for loan losses 1,490 2,141 901 600 Noninterest income 6,638 5,460 5,087 4,008 Noninterest expense 21,809 20,342 19,846 11,179 Income before income taxes 9,667 9,736 7,063 6,471 Income tax expense 1,429 2,121 2,594 1,675 Net income $ 8,238 $ 7,615 $ 4,469 $ 4,796 Net income per common share - basic $ 0.72 $ 0.67 $ 0.43 $ 0.57 Net income per common share - diluted $ 0.72 $ 0.67 $ 0.42 $ 0.57

Nature of Business and Signif56

Nature of Business and Significant Accounting Policies Nature of Business (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)count
Variable Interest Entity, Measure of Activity [Abstract]
Variable Interest Entities, Number Consolidated	0
Financing Receivable, Additional Disclosures [Abstract]
Threshold Period Past Due For Nonaccrual Of Interest	120 days
Threshold Period Past Due for Write-off of Financing Receivable	180 days
MidWestOne Bank
Entity Information [Line Items]
Number of branches	43
FDIC Indemnification Asset
Entity Information [Line Items]
Asset Impairment Charges | $	$ 0

Nature of Business and Signif57

Nature of Business and Significant Accounting Policies Business Combination (Details) - Central Bancshares, Inc. $ in Thousands	May 01, 2015USD ($)shares
Business Acquisition [Line Items]
Cash Paid | $	$ 64,000
Common Stock
Business Acquisition [Line Items]
Number of shares issued in merger | shares	2,723,083

Nature of Business and Signif58

Nature of Business and Significant Accounting Policies Premises and Equipment (Details)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Depreciation Methods	Straight-line
Buildings and leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Buildings and leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	30 years
Furniture and equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Furniture and equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years

Nature of Business and Signif59

Nature of Business and Significant Accounting Policies Stock Repurchase (Details) - Common Stock - USD ($) $ / shares in Units, $ in Millions	Jun. 23, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Jul. 21, 2016	Jul. 17, 2014
Equity, Class of Treasury Stock [Line Items]
Stock Issued During Period, Shares, New Issues		0	300,000	0
Stock Repurchased During Period, Shares		0	0	165,766
January 15 2013 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock Repurchased During Period, Value					$ 3.7
July 17 2014 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount							$ 5
Stock Repurchased During Period, Shares		0	0	165,766
Stock Repurchased During Period, Value				$ 4
Stock Repurchase Program, Remaining Authorized Repurchase Amount			$ 3.8
July 21 2016 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount						$ 5
Stock Repurchased During Period, Shares		0
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 5
Private Placement [Member]
Equity, Class of Treasury Stock [Line Items]
Stock Issued During Period, Shares, New Issues	300,000
Share Price	$ 28

Schedule of Cumulative Other Co

Schedule of Cumulative Other Comprehensive Income (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Cumulative Other Comprehensive Income [Line Items]
Accumulated other comprehensive income, net of tax	$ (1,133)	$ 3,408
Accumulated Other Comprehensive Income (Loss)
Schedule of Cumulative Other Comprehensive Income [Line Items]
Unrealized gains on securities available for sale, net of tax	(1,133)	3,408	$ 5,322
Accumulated other comprehensive income, net of tax	$ (1,133)	$ 3,408	$ 5,322

Business Combination Identifiab

Business Combination Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net (Details) - USD ($) $ / shares in Units, $ in Thousands	May 01, 2015	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Assets
Goodwill			$ 64,654	$ 64,548
Central Bancshares, Inc.
Business Acquisition [Line Items]
Pretax merger related costs			4,600	3,500
Retention and severance compensation expenses			2,100	600
Data processing contract termination expenses			1,900
Professional and legal fees			300	1,900
Service contract termination and other expenses			$ 300	1,000
Goodwill purchase accounting adjustments		$ 100
Assets
Cash and due from banks	$ 28,404
Investment securities	160,775			160,775
Loans	916,973			916,973
Premises and equipment	27,908			27,908
Goodwill	64,654			64,654
FDIC indemnification asset	3,753
Other real estate owned	8,420			8,420
Other assets	14,482			14,482
Total assets	1,239,522			1,211,118
Liabilities [Abstract]
Deposits	1,049,167			1,049,167
Short-term borrowings	16,124			16,124
Junior subordinated notes issued to capital trusts	8,050			8,050
Subordinated notes payable	12,669			12,669
Accrued expenses and other liabilities	11,617			11,617
Total liabilities	1,097,627			1,097,627
Net assets	141,895
Consideration [Abstract]
Market value of common stock at $29.31 per share at May 1, 2015 (2,723,083 shares of common stock issued), net of stock illiquidity discount due to restrictions	77,895
Cash Paid	64,000
Total fair value of consideration	141,895
Central Bancshares, Inc. | Core Deposits
Assets
Finite lived intangible	12,773			12,773
Central Bancshares, Inc. | Trade Names
Assets
Finite lived intangible	$ 1,380			$ 1,380
Central Bancshares, Inc. | Common Stock
Business Acquisition [Line Items]
Number of shares issued in merger	2,723,083
Common Stock | Central Bancshares, Inc.
Consideration [Abstract]
Business acquisition, share price	$ 29.31

Business Combination Acquired L

Business Combination Acquired Loans (Details) - Central Bancshares, Inc. $ in Thousands	May 01, 2015USD ($)
Business Acquisition [Line Items]
Contractually required principal and interest payments, purchased credit impaired loans	$ 36,886
Nonaccretable difference, purchased credit impaired loans	(6,675)
Principal cash flows expected to be collected, purchased credit impaired loans	30,211
Accretable difference, purchased credit impaired loans	(1,882)
Fair value of acquired loans, purchased credit impaired loans	28,329
Contractually required principal and interest payments, purchased non-credit impaired loans	905,314
Nonaccretable difference, purchased non-credit impaired loans	0
Principal cash flows expected to be collected, purchased non-credit impaired loans	905,314
Accretable difference, purchased non-credit impaired loans	(16,670)
Fair value of acquired loans, purchased non-credit impaired loans	888,644
Purchased non-credit impaired loans, accretable discount, estimated uncollectible	$ 10,400

Business Combination Pro Forma

Business Combination Pro Forma Information (Details) - Central Bancshares, Inc. $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)
Business Acquisition [Line Items]
Business acquisition, pro forma revenue (net interest income plus noninterest income)	$ 128,613
Business acquisition, pro forma net income	$ 25,799

Schedule of Available for Sale

Schedule of Available for Sale Securities(Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	$ 479,390	$ 421,740
Gross unrealized gains	4,160	7,751
Gross unrealized losses	6,032	2,250
Available for sale	477,518	427,241
Debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	478,131	420,490
Gross unrealized gains	4,094	7,701
Gross unrealized losses	5,974	2,212
Available for sale	476,251	425,979
US Treasury securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis		6,931
Gross unrealized gains		0
Gross unrealized losses		21
Available for sale		6,910
U.S. Government agencies and corporations
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	5,895	26,600
Gross unrealized gains	10	99
Gross unrealized losses	0	46
Available for sale	5,905	26,653
State and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	162,145	176,794
Gross unrealized gains	3,545	6,662
Gross unrealized losses	418	72
Available for sale	165,272	183,384
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	61,606	56,950
Gross unrealized gains	315	569
Gross unrealized losses	567	457
Available for sale	61,354	57,062
Collateralized mortgage obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	175,506	107,613
Gross unrealized gains	148	321
Gross unrealized losses	4,387	1,530
Available for sale	171,267	106,404
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	72,979	45,602
Gross unrealized gains	76	50
Gross unrealized losses	602	86
Available for sale	72,453	45,566
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Amortized cost basis	1,259	1,250
Gross unrealized gains	66	50
Gross unrealized losses	58	38
Available for sale	$ 1,267	$ 1,262

Schedule of Held to Maturity Se

Schedule of Held to Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity	$ 168,392	$ 118,423
Gross unrealized gains	310	933
Gross unrealized losses	3,910	1,122
Estimated fair value of investment securities held to maturity	164,792	118,234
State and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity	107,941	66,454
Gross unrealized gains	156	928
Gross unrealized losses	2,713	110
Estimated fair value of investment securities held to maturity	105,384	67,272
Mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity	2,398	3,920
Gross unrealized gains	5	4
Gross unrealized losses	34	38
Estimated fair value of investment securities held to maturity	2,369	3,886
Collateralized mortgage obligations
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity	26,036	30,505
Gross unrealized gains		1
Gross unrealized losses	598	459
Estimated fair value of investment securities held to maturity	25,438	30,047
Corporate debt securities
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity	32,017	17,544
Gross unrealized gains	149
Gross unrealized losses	565	515
Estimated fair value of investment securities held to maturity	$ 31,601	$ 17,029

Available for Sale Securities i

Available for Sale Securities in Continuous Loss Position (Details) $ in Thousands	Dec. 31, 2016USD ($)count	Dec. 31, 2015USD ($)count
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss positions, number of positions | count	124	83
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 260,915	$ 144,915
Available for sale securities, continuous unrealized loss position, less than 12 months, accumulated loss	5,101	1,054
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	18,168	35,392
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	931	1,196
Available for sale securities, continuous unrealized loss position, fair value	279,083	180,307
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 6,032	$ 2,250
US Treasury securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss positions, number of positions | count		1
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value		$ 6,910
Available for sale securities, continuous unrealized loss position, less than 12 months, accumulated loss		21
Available for sale securities, continuous unrealized loss position, fair value		6,910
Available for sale securities, continuous unrealized loss position, accumulated loss		$ 21
U.S. Government agencies and corporations
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss positions, number of positions | count		1
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value		$ 4,890
Available for sale securities, continuous unrealized loss position, less than 12 months, accumulated loss		46
Available for sale securities, continuous unrealized loss position, fair value		4,890
Available for sale securities, continuous unrealized loss position, accumulated loss		$ 46
State and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss positions, number of positions | count	63	22
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 24,574	$ 8,419
Available for sale securities, continuous unrealized loss position, less than 12 months, accumulated loss	389	24
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	427	3,177
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	29	48
Available for sale securities, continuous unrealized loss position, fair value	25,001	11,596
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 418	$ 72
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss positions, number of positions | count	20	27
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 40,752	$ 37,753
Available for sale securities, continuous unrealized loss position, less than 12 months, accumulated loss	566	457
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	23
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	1
Available for sale securities, continuous unrealized loss position, fair value	40,775	37,753
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 567	$ 457
Collateralized mortgage obligations
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss positions, number of positions | count	29	23
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 140,698	$ 56,447
Available for sale securities, continuous unrealized loss position, less than 12 months, accumulated loss	3,544	420
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	16,776	31,253
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	843	1,110
Available for sale securities, continuous unrealized loss position, fair value	157,474	87,700
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 4,387	$ 1,530
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss positions, number of positions | count	11	8
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 54,891	$ 30,496
Available for sale securities, continuous unrealized loss position, less than 12 months, accumulated loss	602	86
Available for sale securities, continuous unrealized loss position, fair value	54,891	30,496
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 602	$ 86
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss positions, number of positions | count	1	1
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	$ 942	$ 962
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	58	38
Available for sale securities, continuous unrealized loss position, fair value	942	962
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 58	$ 38

Held to Maturity Securities in

Held to Maturity Securities in Continuous Loss Position (Details) $ in Thousands	Dec. 31, 2016USD ($)count	Dec. 31, 2015USD ($)count
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | count	203	50
Held to maturity securities, continuous unrealized loss position, less than twelve months, fair value	$ 105,582	$ 51,245
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	3,303	760
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value	8,947	10,136
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss	607	362
Held to maturity securities, continuous unrealized loss position, fair value	114,529	61,381
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 3,910	$ 1,122
State and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | count	180	32
Held to maturity securities, continuous unrealized loss position, less than twelve months, fair value	$ 65,174	$ 9,345
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	2,713	93
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value		2,040
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss		17
Held to maturity securities, continuous unrealized loss position, fair value	65,174	11,385
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 2,713	$ 110
Mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | count	5	5
Held to maturity securities, continuous unrealized loss position, less than twelve months, fair value	$ 2,246	$ 3,723
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	34	38
Held to maturity securities, continuous unrealized loss position, fair value	2,246	3,723
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 34	$ 38
Collateralized mortgage obligations
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | count	7	7
Held to maturity securities, continuous unrealized loss position, less than twelve months, fair value	$ 18,964	$ 22,571
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	369	320
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value	6,435	7,416
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss	229	139
Held to maturity securities, continuous unrealized loss position, fair value	25,399	29,987
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 598	$ 459
Corporate debt securities
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | count	11	6
Held to maturity securities, continuous unrealized loss position, less than twelve months, fair value	$ 19,198	$ 15,606
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	187	309
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value	2,512	680
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss	378	206
Held to maturity securities, continuous unrealized loss position, fair value	21,710	16,286
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 565	$ 515

Investments Classified by Contr

Investments Classified by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Due in one year or less, amortized cost	$ 11,422
Due after one year through five years, amortized cost	122,263
Due after five years through ten years, amortized cost	95,598
Due after ten years, amortized cost	11,736
Debt securities without a single maturity date, amortized cost	237,112
Total, amortized cost	478,131
Due in one year or less, estimated fair value	11,468
Due after one year through five years, estimated fair value	123,237
Due after five years through ten years, estimated fair value	97,246
Due after ten years, estimated fair value	11,679
Debt securities without a single maturity date, estimated fair value	232,621
Total, estimated fair value	476,251
Held-to-maturity Securities, Debt Maturities [Abstract]
Due in one year or less, amortized cost	2,385
Due after one year through five years, amortized cost	9,780
Due after five years through ten years, amortized cost	72,063
Due after ten years, amortized cost	55,730
Debt securities without a single maturity date, amortized cost	28,434
Held to maturity	168,392	$ 118,423
Due in one year or less, estimated fair value	2,384
Due after one year through five years, estimated fair value	9,700
Due after five years through ten years, estimated fair value	71,314
Due after ten years, estimated fair value	53,587
Debt securities without a single maturity date, estimated fair value	27,807
Estimated fair value	$ 164,792	$ 118,234

Investment Securities Realized

Investment Securities Realized Gains and Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Gain (Loss) on Investments [Line Items]
Total	$ 464	$ 1,011	$ 1,227
Debt securities
Gain (Loss) on Investments [Line Items]
Gross realized gains	469	1,265	1,463
Gross realized losses	5	442	236
Total	464	823	1,227
Equity securities
Gain (Loss) on Investments [Line Items]
Gross realized gains	0	188
Gross realized losses	0	0
Other-than-temporary impairment	$ 0	0
Total		$ 188	$ 0

Investment Securities Investmen

Investment Securities Investment Securities Textual References (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities pledged as collateral	$ 212,100	$ 321,600
Available for sale	477,518	427,241
Investment in mortgage-backed and collateralized mortgage securities, amortized cost basis	479,390	421,740
Proceeds from sales of available for sale securities	23,381	116,829	$ 33,457
State and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Available for sale	165,272	183,384
Investment in mortgage-backed and collateralized mortgage securities, amortized cost basis	162,145	176,794
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale	72,453	45,566
Investment in mortgage-backed and collateralized mortgage securities, amortized cost basis	72,979	45,602
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale	1,267	1,262
Other-than-temporary impairment losses, equity securities	0	0
Investment in mortgage-backed and collateralized mortgage securities, amortized cost basis	1,259	$ 1,250
Community Reinvestment Act qualified investment
Schedule of Available-for-sale Securities [Line Items]
Available for sale	900
Banks, Trust and Insurance, Equities | Equity securities
Schedule of Available-for-sale Securities [Line Items]
Available for sale	$ 300
Total Obligations of State and Political Subdivisions | Geographic Concentration Risk | IOWA | State and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Concentration risk, percentage	58.00%
Total Obligations of State and Political Subdivisions | Geographic Concentration Risk | MINNESOTA | State and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Concentration risk, percentage	21.00%

Allowance for Loan Losses and R

Allowance for Loan Losses and Recorded Investment in Loan Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	$ 4,351	$ 3,714
Loans receivable, allowance for credit losses, collectively evaluated for impairment	16,878	15,619
Certain loans acquired in transfer not accounted for as debt securities, allowance for loan losses	621	94
Loans and leases receivable, allowance for loan losses	21,850	19,427	$ 16,363	$ 16,179
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	32,178	40,238
Loans receivable, collectively evaluated for impairment	2,110,167	2,086,112
Loans receivable, purchased credit impaired	22,798	25,592
Loans and leases receivable, gross	2,165,143	2,151,942
Agricultural Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	62	51
Loans receivable, allowance for credit losses, collectively evaluated for impairment	1,941	1,366
Loans and leases receivable, allowance for loan losses	2,003	1,417	1,506	1,358
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	5,339	3,072
Loans receivable, collectively evaluated for impairment	108,004	118,642
Loans and leases receivable, gross	113,343	121,714
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	2,066	489
Loans receivable, allowance for credit losses, collectively evaluated for impairment	4,199	4,962
Loans and leases receivable, allowance for loan losses	6,274	5,451	5,780	4,980
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	11,434	7,718
Loans receivable, collectively evaluated for impairment	449,380	461,275
Loans and leases receivable, gross	460,970	469,249
Commercial Portfolio Segment | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Certain loans acquired in transfer not accounted for as debt securities, allowance for loan losses	9
Financing Receivable [Abstract]
Loans receivable, purchased credit impaired	156	256
Commercial Real Estate Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	1,924	2,786
Loans receivable, allowance for credit losses, collectively evaluated for impairment	7,692	5,718
Loans and leases receivable, allowance for loan losses	9,860	8,556	4,399	5,294
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	11,450	23,697
Loans receivable, collectively evaluated for impairment	1,036,049	950,207
Loans and leases receivable, gross	1,064,243	991,941
Commercial Real Estate Portfolio Segment | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Certain loans acquired in transfer not accounted for as debt securities, allowance for loan losses	244	52
Financing Receivable [Abstract]
Loans receivable, purchased credit impaired	16,744	18,037
Residential Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	299	387
Loans receivable, allowance for credit losses, collectively evaluated for impairment	2,791	3,539
Loans and leases receivable, allowance for loan losses	3,458	3,968	3,167	3,185
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	3,955	5,725
Loans receivable, collectively evaluated for impairment	480,143	517,482
Loans and leases receivable, gross	489,996	530,506
Residential Portfolio Segment | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Certain loans acquired in transfer not accounted for as debt securities, allowance for loan losses	368	42
Financing Receivable [Abstract]
Loans receivable, purchased credit impaired	5,898	7,299
Consumer Other Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment		1
Loans receivable, allowance for credit losses, collectively evaluated for impairment	255	408
Loans and leases receivable, allowance for loan losses	255	409	323	275
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment		26
Loans receivable, collectively evaluated for impairment	36,591	38,506
Loans and leases receivable, gross	$ 36,591	38,532
Unallocated Financing Receivables
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, collectively evaluated for impairment		(374)
Loans and leases receivable, allowance for loan losses		$ (374)	$ 1,188	$ 1,087

Allowance for Loan Loss Activit

Allowance for Loan Loss Activity (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				$ 19,427				$ 16,363	$ 19,427	$ 16,363	$ 16,179
Charge-offs									6,081	2,622	1,361
Recoveries									521	554	345
Provision for loan losses	$ 4,742	$ 1,005	$ 1,171	1,065	$ 1,490	$ 2,141	$ 901	600	7,983	5,132	1,200
Ending balance	21,850				19,427				21,850	19,427	16,363
Agricultural Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				1,417				1,506	1,417	1,506	1,358
Charge-offs									1,204	245	26
Recoveries									33	1	10
Provision for loan losses									1,757	155	164
Ending balance	2,003				1,417				2,003	1,417	1,506
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				5,451				5,780	5,451	5,780	4,980
Charge-offs									3,066	692	685
Recoveries									124	372	217
Provision for loan losses									3,765	(9)	1,268
Ending balance	6,274				5,451				6,274	5,451	5,780
Commercial Real Estate Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				8,556				4,399	8,556	4,399	5,294
Charge-offs									931	853	165
Recoveries									192	7	61
Provision for loan losses									2,043	5,003	(791)
Ending balance	9,860				8,556				9,860	8,556	4,399
Residential Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				3,968				3,167	3,968	3,167	3,185
Charge-offs									782	740	409
Recoveries									157	143	22
Provision for loan losses									115	1,398	369
Ending balance	3,458				3,968				3,458	3,968	3,167
Consumer Other Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				409				323	409	323	275
Charge-offs									98	92	76
Recoveries									15	31	35
Provision for loan losses									(71)	147	89
Ending balance	$ 255				409				255	409	323
Unallocated Financing Receivables
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				$ (374)				$ 1,188	(374)	1,188	1,087
Provision for loan losses									$ 374	(1,562)	101
Ending balance					$ (374)					$ (374)	$ 1,188

New Troubled Debt Restructuring

New Troubled Debt Restructurings During Period (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)count	Dec. 31, 2015USD ($)count	Dec. 31, 2014USD ($)count
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | count	5	1	2
Financing receivable, modifications, pre-modification recorded investment	$ 1,490	$ 151	$ 1,690
Financing receivable, modifications, post-modification recorded investment	$ 1,190	$ 151	$ 1,697
Contractual Interest Rate Reduction | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | count	2	1	1
Financing receivable, modifications, pre-modification recorded investment	$ 394	$ 151	$ 285
Financing receivable, modifications, post-modification recorded investment	$ 394	$ 151	$ 292
Contractual Interest Rate Reduction | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | count	1
Financing receivable, modifications, pre-modification recorded investment	$ 71
Financing receivable, modifications, post-modification recorded investment	$ 71
Extended Maturity | Agricultural Loan Financing Receivable
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | count	1
Financing receivable, modifications, pre-modification recorded investment	$ 25
Financing receivable, modifications, post-modification recorded investment	$ 25
Extended Maturity | Commercial and Industrical Loan Financing Receivable
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | count			1
Financing receivable, modifications, pre-modification recorded investment			$ 1,405
Financing receivable, modifications, post-modification recorded investment			$ 1,405
Other Concession | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts | count	1
Financing receivable, modifications, pre-modification recorded investment	$ 1,000
Financing receivable, modifications, post-modification recorded investment	$ 700

Loans by Internally Assigned Cr

Loans by Internally Assigned Credit Quality Indicators (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	$ 2,165,143	$ 2,151,942
Purchased credit-impaired loans, internally classified as other than pass	15,300	23,700
Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	113,343	121,714
Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	459,481	467,412
Commercial Credit Card Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	1,489	1,377
Overdraft Deposit Account Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		1,483
Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	126,685	120,753
Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	94,979	89,084
Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	136,003	121,763
Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	706,576	660,341
Commercial Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	1,064,243	991,941
Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	372,233	428,233
Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	117,763	102,273
Residential Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	489,996	530,506
Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	36,591	37,509
Pass
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	2,042,952	2,020,162
Pass | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	95,103	111,361
Pass | Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	429,392	436,857
Pass | Commercial Credit Card Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	1,489	1,354
Pass | Overdraft Deposit Account Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		1,168
Pass | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	121,982	114,640
Pass | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	83,563	82,442
Pass | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	134,975	119,139
Pass | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	666,767	609,651
Pass | Commercial Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	1,007,287	925,872
Pass | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	359,029	410,143
Pass | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	114,233	96,223
Pass | Residential Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	473,262	506,366
Pass | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	36,419	37,184
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	62,206	52,736
Special Mention | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	14,089	8,536
Special Mention | Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	11,065	12,893
Special Mention | Commercial Credit Card Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		19
Special Mention | Overdraft Deposit Account Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		100
Special Mention | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	2,732	2,406
Special Mention | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	8,986	2,408
Special Mention | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	548	371
Special Mention | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	20,955	19,402
Special Mention | Commercial Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	33,221	24,587
Special Mention | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	2,202	4,813
Special Mention | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	1,628	1,782
Special Mention | Residential Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	3,830	6,595
Special Mention | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	1	6
Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	59,940	78,699
Substandard | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	4,151	1,817
Substandard | Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	19,016	17,652
Substandard | Commercial Credit Card Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		4
Substandard | Overdraft Deposit Account Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		215
Substandard | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	1,971	3,707
Substandard | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	2,430	4,234
Substandard | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	480	2,253
Substandard | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	18,854	31,288
Substandard | Commercial Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	23,735	41,482
Substandard | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	11,002	13,042
Substandard | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	1,902	4,209
Substandard | Residential Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	12,904	17,251
Substandard | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	134	278
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	45	345
Doubtful | Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	8	10
Doubtful | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		235
Doubtful | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		59
Doubtful | Residential Real Estate Total
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net		294
Doubtful | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, net	$ 37	$ 41

Amounts and Categories of Impai

Amounts and Categories of Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	$ 17,212	$ 28,701
Impaired financing receivable, with no related allowance, unpaid principal balance	19,587	30,468
Impaired financing receivable, with related allowance, recorded investment	14,966	11,537
Impaired financing receivable, with related allowance, unpaid principal balance	15,032	11,703
Impaired financing receivable, related allowance	4,351	3,714
Impaired financing receivable, recorded investment	32,178	40,238
Impaired financing receivable, unpaid principal balance	34,619	42,171
Impaired financing receivable, with no related allowance, average recorded investment	17,807	29,778	$ 7,648
Impaired financing receivable, with no related allowance, interest income, accrual method	479	1,256	865
Impaired financing receivable, with related allowance, average recorded investment	15,292	11,695	6,048
Impaired financing receivable, with related allowance, interest income, accrual method	164	511	564
Impaired financing receivable, average recorded investment	33,099	41,473	13,696
Impaired financing receivable, interest income, accrual method	643	1,767	1,429
Loans and leases receivable, impaired, commitment to lend	0
Agricultural Loan Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	3,673	1,512
Impaired financing receivable, with no related allowance, unpaid principal balance	4,952	2,084
Impaired financing receivable, with related allowance, recorded investment	1,666	1,560
Impaired financing receivable, with related allowance, unpaid principal balance	1,669	1,560
Impaired financing receivable, related allowance	62	51
Impaired financing receivable, recorded investment	5,339	3,072
Impaired financing receivable, unpaid principal balance	6,621	3,644
Impaired financing receivable, with no related allowance, average recorded investment	3,815	1,533	1,413
Impaired financing receivable, with no related allowance, interest income, accrual method	88	58	211
Impaired financing receivable, with related allowance, average recorded investment	1,678	1,572	1,627
Impaired financing receivable, with related allowance, interest income, accrual method	46	48	203
Impaired financing receivable, average recorded investment	5,493	3,105	3,040
Impaired financing receivable, interest income, accrual method	134	106	414
Commercial and Industrical Loan Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	6,211	6,487
Impaired financing receivable, with no related allowance, unpaid principal balance	6,259	6,752
Impaired financing receivable, with related allowance, recorded investment	5,223	1,231
Impaired financing receivable, with related allowance, unpaid principal balance	5,223	1,258
Impaired financing receivable, related allowance	2,066	489
Impaired financing receivable, recorded investment	11,434	7,718
Impaired financing receivable, unpaid principal balance	11,482	8,010
Impaired financing receivable, with no related allowance, average recorded investment	6,540	6,769	2,234
Impaired financing receivable, with no related allowance, interest income, accrual method	79	424	160
Impaired financing receivable, with related allowance, average recorded investment	5,277	1,313	1,044
Impaired financing receivable, with related allowance, interest income, accrual method	74	67	104
Impaired financing receivable, average recorded investment	11,817	8,082	3,278
Impaired financing receivable, interest income, accrual method	153	491	264
Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	445	321
Impaired financing receivable, with no related allowance, unpaid principal balance	1,170	448
Impaired financing receivable, with related allowance, recorded investment	263	34
Impaired financing receivable, with related allowance, unpaid principal balance	270	34
Impaired financing receivable, related allowance	21	34
Impaired financing receivable, recorded investment	708	355
Impaired financing receivable, unpaid principal balance	1,440	482
Impaired financing receivable, with no related allowance, average recorded investment	390	325	49
Impaired financing receivable, with no related allowance, interest income, accrual method	54	7
Impaired financing receivable, with related allowance, average recorded investment	263	34	35
Impaired financing receivable, with related allowance, interest income, accrual method	3		3
Impaired financing receivable, average recorded investment	653	359	84
Impaired financing receivable, interest income, accrual method	57	7	3
Farmland Loan Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	2,230	2,711
Impaired financing receivable, with no related allowance, unpaid principal balance	2,380	2,870
Impaired financing receivable, with related allowance, recorded investment		69
Impaired financing receivable, with related allowance, unpaid principal balance		69
Impaired financing receivable, related allowance		3
Impaired financing receivable, recorded investment	2,230	2,780
Impaired financing receivable, unpaid principal balance	2,380	2,939
Impaired financing receivable, with no related allowance, average recorded investment	2,389	2,743	2,288
Impaired financing receivable, with no related allowance, interest income, accrual method	97	128	456
Impaired financing receivable, with related allowance, average recorded investment		70	74
Impaired financing receivable, with related allowance, interest income, accrual method		2	3
Impaired financing receivable, average recorded investment	2,389	2,813	2,362
Impaired financing receivable, interest income, accrual method	97	130	459
Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment		1,632
Impaired financing receivable, with no related allowance, unpaid principal balance		1,798
Impaired financing receivable, with related allowance, recorded investment		224
Impaired financing receivable, with related allowance, unpaid principal balance		224
Impaired financing receivable, related allowance		73
Impaired financing receivable, recorded investment		1,856
Impaired financing receivable, unpaid principal balance		2,022
Impaired financing receivable, with no related allowance, average recorded investment		1,833
Impaired financing receivable, with no related allowance, interest income, accrual method		68
Impaired financing receivable, with related allowance, average recorded investment		226
Impaired financing receivable, with related allowance, interest income, accrual method		6
Impaired financing receivable, average recorded investment		2,059
Impaired financing receivable, interest income, accrual method		74
Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	2,224	12,230
Impaired financing receivable, with no related allowance, unpaid principal balance	2,384	12,642
Impaired financing receivable, with related allowance, recorded investment	6,288	6,476
Impaired financing receivable, with related allowance, unpaid principal balance	6,344	6,478
Impaired financing receivable, related allowance	1,903	2,676
Impaired financing receivable, recorded investment	8,512	18,706
Impaired financing receivable, unpaid principal balance	8,728	19,120
Impaired financing receivable, with no related allowance, average recorded investment	2,243	12,772	975
Impaired financing receivable, with no related allowance, interest income, accrual method	60	446
Impaired financing receivable, with related allowance, average recorded investment	6,515	6,528	551
Impaired financing receivable, with related allowance, interest income, accrual method		344	43
Impaired financing receivable, average recorded investment	8,758	19,300	1,526
Impaired financing receivable, interest income, accrual method	60	790	43
Commercial Real Estate Total
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	4,899	16,894
Impaired financing receivable, with no related allowance, unpaid principal balance	5,934	17,758
Impaired financing receivable, with related allowance, recorded investment	6,551	6,803
Impaired financing receivable, with related allowance, unpaid principal balance	6,614	6,805
Impaired financing receivable, related allowance	1,924	2,786
Impaired financing receivable, recorded investment	11,450	23,697
Impaired financing receivable, unpaid principal balance	12,548	24,563
Impaired financing receivable, with no related allowance, average recorded investment	5,022	17,673	3,312
Impaired financing receivable, with no related allowance, interest income, accrual method	211	649	456
Impaired financing receivable, with related allowance, average recorded investment	6,778	6,858	660
Impaired financing receivable, with related allowance, interest income, accrual method	3	352	49
Impaired financing receivable, average recorded investment	11,800	24,531	3,972
Impaired financing receivable, interest income, accrual method	214	1,001	505
Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	2,429	2,494
Impaired financing receivable, with no related allowance, unpaid principal balance	2,442	2,533
Impaired financing receivable, with related allowance, recorded investment	1,526	1,919
Impaired financing receivable, with related allowance, unpaid principal balance	1,526	2,056
Impaired financing receivable, related allowance	299	383
Impaired financing receivable, recorded investment	3,955	4,413
Impaired financing receivable, unpaid principal balance	3,968	4,589
Impaired financing receivable, with no related allowance, average recorded investment	2,430	2,469	547
Impaired financing receivable, with no related allowance, interest income, accrual method	101	81	32
Impaired financing receivable, with related allowance, average recorded investment	1,559	1,928	2,612
Impaired financing receivable, with related allowance, interest income, accrual method	41	44	203
Impaired financing receivable, average recorded investment	3,989	4,397	3,159
Impaired financing receivable, interest income, accrual method	142	125	235
Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment		1,297
Impaired financing receivable, with no related allowance, unpaid principal balance		1,308
Impaired financing receivable, with related allowance, recorded investment		15
Impaired financing receivable, with related allowance, unpaid principal balance		15
Impaired financing receivable, related allowance		4
Impaired financing receivable, recorded investment		1,312
Impaired financing receivable, unpaid principal balance		1,323
Impaired financing receivable, with no related allowance, average recorded investment		1,313	134
Impaired financing receivable, with no related allowance, interest income, accrual method		42	6
Impaired financing receivable, with related allowance, average recorded investment		15	74
Impaired financing receivable, average recorded investment		1,328	208
Impaired financing receivable, interest income, accrual method		42	6
Residential Real Estate Total
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment	2,429	3,791
Impaired financing receivable, with no related allowance, unpaid principal balance	2,442	3,841
Impaired financing receivable, with related allowance, recorded investment	1,526	1,934
Impaired financing receivable, with related allowance, unpaid principal balance	1,526	2,071
Impaired financing receivable, related allowance	299	387
Impaired financing receivable, recorded investment	3,955	5,725
Impaired financing receivable, unpaid principal balance	3,968	5,912
Impaired financing receivable, with no related allowance, average recorded investment	2,430	3,782	681
Impaired financing receivable, with no related allowance, interest income, accrual method	101	123	38
Impaired financing receivable, with related allowance, average recorded investment	1,559	1,943	2,686
Impaired financing receivable, with related allowance, interest income, accrual method	41	44	203
Impaired financing receivable, average recorded investment	3,989	5,725	3,367
Impaired financing receivable, interest income, accrual method	$ 142	167	241
Consumer Loan Financing Receivable
Financing Receivable, Impaired [Line Items]
Impaired financing receivable, with no related allowance, recorded investment		17
Impaired financing receivable, with no related allowance, unpaid principal balance		33
Impaired financing receivable, with related allowance, recorded investment		9
Impaired financing receivable, with related allowance, unpaid principal balance		9
Impaired financing receivable, related allowance		1
Impaired financing receivable, recorded investment		26
Impaired financing receivable, unpaid principal balance		42
Impaired financing receivable, with no related allowance, average recorded investment		21	8
Impaired financing receivable, with no related allowance, interest income, accrual method		2
Impaired financing receivable, with related allowance, average recorded investment		9	31
Impaired financing receivable, with related allowance, interest income, accrual method			5
Impaired financing receivable, average recorded investment		30	39
Impaired financing receivable, interest income, accrual method		$ 2	$ 5

Past Due Loan Aging (Details)

Past Due Loan Aging (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	$ 29,347	$ 13,800
Loans current	2,135,796	2,138,142
Total Loans Receivable	2,165,143	2,151,942
Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	443	378
Loans current	112,900	121,336
Total Loans Receivable	113,343	121,714
Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	12,562	2,400
Loans current	446,919	465,012
Total Loans Receivable	459,481	467,412
Commercial Credit Card Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		23
Loans current	1,489	1,354
Total Loans Receivable	1,489	1,377
Overdraft Deposit Account Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		214
Loans current		1,269
Total Loans Receivable		1,483
Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	927	415
Loans current	125,758	120,338
Total Loans Receivable	126,685	120,753
Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	464	200
Loans current	94,515	88,884
Total Loans Receivable	94,979	89,084
Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	129	224
Loans current	135,874	121,539
Total Loans Receivable	136,003	121,763
Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	8,656	3,580
Loans current	697,920	656,761
Total Loans Receivable	706,576	660,341
Commercial Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	10,176	4,419
Loans current	1,054,067	987,522
Total Loans Receivable	1,064,243	991,941
Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	5,322	5,676
Loans current	366,911	422,557
Total Loans Receivable	372,233	428,233
Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	738	605
Loans current	117,025	101,668
Total Loans Receivable	117,763	102,273
Residential Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	6,060	6,281
Loans current	483,936	524,225
Total Loans Receivable	489,996	530,506
Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	106	85
Loans current	36,485	37,424
Total Loans Receivable	36,591	37,509
Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	2,003	2,261
Loans current	20,795	23,331
Total Loans Receivable	22,798	25,592
Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	8,238	5,393
Financing Receivables, 30 to 59 Days Past Due | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	44	19
Financing Receivables, 30 to 59 Days Past Due | Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	2,615	1,046
Financing Receivables, 30 to 59 Days Past Due | Commercial Credit Card Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		2
Financing Receivables, 30 to 59 Days Past Due | Overdraft Deposit Account Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		175
Financing Receivables, 30 to 59 Days Past Due | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	630
Financing Receivables, 30 to 59 Days Past Due | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	373	120
Financing Receivables, 30 to 59 Days Past Due | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	1,238	1,190
Financing Receivables, 30 to 59 Days Past Due | Commercial Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	2,241	1,310
Financing Receivables, 30 to 59 Days Past Due | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	2,851	2,611
Financing Receivables, 30 to 59 Days Past Due | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	437	168
Financing Receivables, 30 to 59 Days Past Due | Residential Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	3,288	2,779
Financing Receivables, 30 to 59 Days Past Due | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	50	62
Financing Receivables, 30 to 59 Days Past Due | Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	965	473
Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	2,502	3,098
Financing Receivables, 60 to 89 Days Past Due | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		190
Financing Receivables, 60 to 89 Days Past Due | Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	293	710
Financing Receivables, 60 to 89 Days Past Due | Commercial Credit Card Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		17
Financing Receivables, 60 to 89 Days Past Due | Overdraft Deposit Account Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		8
Financing Receivables, 60 to 89 Days Past Due | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	129
Financing Receivables, 60 to 89 Days Past Due | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	763	754
Financing Receivables, 60 to 89 Days Past Due | Commercial Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	892	754
Financing Receivables, 60 to 89 Days Past Due | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	1,143	1,293
Financing Receivables, 60 to 89 Days Past Due | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	151	120
Financing Receivables, 60 to 89 Days Past Due | Residential Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	1,294	1,413
Financing Receivables, 60 to 89 Days Past Due | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	23	6
Financing Receivables, 60 to 89 Days Past Due | Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	489	799
Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	18,607	5,309
Financing Receivables, Equal to Greater than 90 Days Past Due | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	399	169
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	9,654	644
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial Credit Card Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		4
Financing Receivables, Equal to Greater than 90 Days Past Due | Overdraft Deposit Account Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		31
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	297	415
Financing Receivables, Equal to Greater than 90 Days Past Due | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	91	80
Financing Receivables, Equal to Greater than 90 Days Past Due | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due		224
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	6,655	1,636
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	7,043	2,355
Financing Receivables, Equal to Greater than 90 Days Past Due | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	1,328	1,772
Financing Receivables, Equal to Greater than 90 Days Past Due | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	150	317
Financing Receivables, Equal to Greater than 90 Days Past Due | Residential Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	1,478	2,089
Financing Receivables, Equal to Greater than 90 Days Past Due | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	33	17
Financing Receivables, Equal to Greater than 90 Days Past Due | Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due	$ 549	$ 989

Nonaccrual and 90+ Days Past Du

Nonaccrual and 90+ Days Past Due and Still Accruing (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	$ 20,668	$ 4,012
Loans past due 90 days or more and still accruing	485	284
Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	2,690	172
Commercial and Industrical Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	8,358	575
Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	780	95
Loans past due 90 days or more and still accruing	95
Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	227	20
Loans past due 90 days or more and still accruing		80
Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual		224
Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	7,360	1,452
Commercial Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	8,367	1,791
Loans past due 90 days or more and still accruing	95	80
Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	1,127	1,182
Loans past due 90 days or more and still accruing	375	199
Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	116	281
Loans past due 90 days or more and still accruing	15
Residential Real Estate Total
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	1,243	1,463
Loans past due 90 days or more and still accruing	390	199
Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	10	11
Loans past due 90 days or more and still accruing		5
Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual or 90 days past due and still accruing	2,600	4,100
Discount, nonaccrual or 90 days past due and still accruing	$ 500	$ 1,400

Loans Receivable and the Allo78

Loans Receivable and the Allowance for Loan Losses Accretable Yield for Loans Acquired and Accounted for Under ASC 310-30 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Loans and Leases Receivable Disclosure [Abstract]
Balance at beginning of year	$ 1,446	$ 0
Purchases	0	1,882
Accretions	(3,287)	(666)
Reclassifications from nonaccretable difference	3,802	230
Balance at end of year	$ 1,961	$ 1,446

Loans Textual References (Detai

Loans Textual References (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)quarters	Dec. 31, 2015USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
Covered loans, contractual balance	$ 74.9	$ 108.7
Covered loans, net of discounts	$ 72.4	103
Covered loans, FDIC coverage end date	Oct. 7, 2021
Unpaid principal balance, loans pledged to the FHLB	$ 498.3	558.8
Allowance for loan losses, unallocated maximum overage percentage	20.00%
Allowance for loan losses, unallocated maximum shortage percentage	5.00%
Loans reviewed collectively for impairment, historical loss lookback, number of quarters | quarters	20
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Allowance for Credit Losses [Line Items]
Purchased credit-impaired loans, outstanding balance	$ 26.2	33
Purchased credit-impaired loans, discount	$ 3.4	$ 7.4

Loan Pool Participations Carryi

Loan Pool Participations Carrying Value Rollforward (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)
Loan Pool Participations [Abstract]
Balance at beginning of year	$ 19,332
Principal payments and sale proceeds	18,823
Net charge-offs	509
Balance at end of year	0
Loan pool participations, face value	$ 0

Loan Pool Participations Accret

Loan Pool Participations Accretable Yield Rollforward (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)
Loan Pool Participation, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	$ 1,579
Additions	0
Accretions	(1,579)
Reclass to nonaccretable difference	0
Cash flows expected to be collected at acquisition	0
Basis in acquired loans at acquisition	$ 0

Premises and Equipment (Details

Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 98,665	$ 102,273
Accumulated depreciation and amortization	23,622	26,071
Premises and equipment, net	75,043	76,202
Depreciation expense	4,555	3,284	$ 2,174
Land
Property, Plant and Equipment [Line Items]
Premises and equipment	12,970	13,270
Buildings and leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment	68,405	60,871
Furniture and Equipment
Property, Plant and Equipment [Line Items]
Premises and equipment	15,851	17,160
Construction in Progress
Property, Plant and Equipment [Line Items]
Premises and equipment	$ 1,439	$ 10,972

Goodwill and Intangible Asset83

Goodwill and Intangible Assets Schedule of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	May 01, 2015
Goodwill [Line Items]
Goodwill	$ 64,654	$ 64,548
Central Bancshares, Inc.
Goodwill [Line Items]
Goodwill		64,654		$ 64,654
Goodwill acquired during the period	100
MidWestOne Bank
Goodwill [Line Items]
Goodwill impairment loss	$ 0
Central Bank
Goodwill [Line Items]
Goodwill impairment loss		$ 0	$ 0

Goodwill and Intangible Asset84

Goodwill and Intangible Assets Schedule of Indefinite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Trade Names | MidWestOne Bank
Indefinite-lived Intangible Assets [Line Items]
Impairment of indefinite-lived trade name intangible	$ 0	$ 0	$ 0

Schedule of Intangible Assets (

Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Balance, beginning of period	$ 19,141	$ 8,259
Amortization expense	(3,970)	(3,271)	$ (547)
Balance, end of period	15,171	19,141	8,259
Gross carrying amount				$ 28,276	$ 28,276
Accumulated amortization				(13,105)	(9,135)
Net book value	19,141	8,259	8,259	15,171	19,141
Insurance agency intangible
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Balance, beginning of period	275	364
Additions from business combinations		0
Amortization expense	(72)	(89)
Balance, end of period	203	275	364
Gross carrying amount				1,320	1,320
Accumulated amortization				(1,117)	(1,045)
Net book value	$ 275	$ 364	364	203	275
Remaining weighted average useful life (years)	7 years	7 years
Core Deposits
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Balance, beginning of period	$ 10,480	$ 691
Amortization expense	(3,634)	(2,984)
Balance, end of period	6,846	10,480	691
Gross carrying amount				18,206	18,206
Accumulated amortization				(11,360)	(7,726)
Net book value	$ 10,480	$ 691	691	6,846	10,480
Remaining weighted average useful life (years)	5 years	6 years
Trade Names
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Balance, beginning of period	$ 1,203	$ 0
Amortization expense	(243)	(177)
Balance, end of period	960	1,203	0
Gross carrying amount				1,380	1,380
Accumulated amortization				(420)	(177)
Net book value	$ 1,203	$ 0	0	960	1,203
Remaining weighted average useful life (years)	8 years	9 years
Customer list intangible
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Balance, beginning of period	$ 143	$ 164
Additions from business combinations		0
Amortization expense	(21)	(21)
Balance, end of period	122	143	164
Gross carrying amount				330	330
Accumulated amortization				(208)	(187)
Net book value	$ 143	$ 164	164	122	143
Remaining weighted average useful life (years)	7 years	8 years
Trade Names
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Balance, beginning of period	$ 7,040	$ 7,040
Balance, end of period	7,040	7,040	7,040
Gross carrying amount				7,040	7,040
Net book value	$ 7,040	7,040	$ 7,040	$ 7,040	$ 7,040
Central Bancshares, Inc.
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Additions from business combinations		14,153
Central Bancshares, Inc. | Core Deposits
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Additions from business combinations		12,773
Central Bancshares, Inc. | Trade Names
Schedule of Intangible Assets (Excluding Goodwill) [Line Items]
Additions from business combinations		$ 1,380

Schedule of Finite-Lived Intang

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense (Details) $ in Thousands	Dec. 31, 2016USD ($)
Finite-Lived Intangible Assets [Line Items]
Amortization expense, next twelve months	$ 3,125
Amortization expense, year two	2,281
Amortization expense, year three	1,511
Amortization expense, year four	782
Amortization expense, year five	189
Amortization expense, after year five	243
Total	8,131
Insurance agency intangible
Finite-Lived Intangible Assets [Line Items]
Amortization expense, next twelve months	55
Amortization expense, year two	38
Amortization expense, year three	21
Amortization expense, year four	20
Amortization expense, year five	19
Amortization expense, after year five	50
Total	203
Core Deposits
Finite-Lived Intangible Assets [Line Items]
Amortization expense, next twelve months	2,835
Amortization expense, year two	2,037
Amortization expense, year three	1,312
Amortization expense, year four	613
Amortization expense, year five	49
Amortization expense, after year five	0
Total	6,846
Trade Names
Finite-Lived Intangible Assets [Line Items]
Amortization expense, next twelve months	216
Amortization expense, year two	188
Amortization expense, year three	161
Amortization expense, year four	133
Amortization expense, year five	106
Amortization expense, after year five	156
Total	960
Customer list intangible
Finite-Lived Intangible Assets [Line Items]
Amortization expense, next twelve months	19
Amortization expense, year two	18
Amortization expense, year three	17
Amortization expense, year four	16
Amortization expense, year five	15
Amortization expense, after year five	37
Total	$ 122

Other Assets (Details)

Other Assets (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Other Assets [Abstract]
Federal Home Loan Bank Stock	$ 12,800,000	$ 9,832,000
FDIC Indemnification Asset	479,000	4,274,000
Prepaid expenses	1,760,000	2,271,000
Mortgage servicing rights	1,951,000	2,249,000
Federal and state taxes, current	0	1,079,000
Accounts receivable & other miscellaneous assets	1,323,000	2,104,000
Total other assets	18,313,000	21,809,000
Investment in Federal Home Loan Bank Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other than Temporary Impairment Losses, Investments	$ 0	$ 0

Loans Serviced for Others (Deta

Loans Serviced for Others (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Components of Managed Servicing Portfolio [Abstract]
Loans serviced for others	$ 391.8	$ 362.3

Time Deposits, Fiscal Year Matu

Time Deposits, Fiscal Year Maturity (Details) $ in Thousands	Dec. 31, 2016USD ($)
Time Deposits, Fiscal Year Maturity [Abstract]
2,017	$ 402,316
2,018	100,028
2,019	81,325
2,020	27,050
2,021	40,410
Thereafter	753
Time Deposits	$ 651,882

Time Deposits Time Deposit Text

Time Deposits Time Deposit Textual References (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Deposits [Abstract]
Time deposits, $250,000 or more	$ 177.9	$ 162.5
Domestic time deposit, brokered	$ 2.6	$ 2.8

Short-Term Borrowings (Details)

Short-Term Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Short-term Debt [Line Items]
Short-term debt, weighted average interest rate	0.40%	0.31%
Short-term debt	$ 117,871	$ 68,963
Available-for-sale securities pledged as collateral	212,100	321,600
Federal Reserve Bank Advances
Short-term Debt [Line Items]
Short-term debt	0	0
Line of credit facility, maximum borrowing capacity	11,500	11,800
Available-for-sale securities pledged as collateral	$ 12,800	$ 13,100
Federal Funds Purchased
Short-term Debt [Line Items]
Short-term debt, weighted average interest rate	0.83%	0.34%
Short-term debt	$ 35,684	$ 1,500
Securities Sold under Agreements to Repurchase
Short-term Debt [Line Items]
Short-term debt, weighted average interest rate	0.22%	0.31%
Short-term debt	$ 82,187	$ 67,463
Line of Credit
Short-term Debt [Line Items]
Short-term debt	0
Line of credit facility, maximum borrowing capacity	$ 5,000
Debt instrument, issuance date	Apr. 30, 2015
Debt instrument, maturity date	Apr. 27, 2017
London Interbank Offered Rate (LIBOR) | Line of Credit
Short-term Debt [Line Items]
Description of variable rate basis	one-month LIBOR
Basis spread on variable rate	2.00%

Subordinated Notes Payable (Det

Subordinated Notes Payable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	May 01, 2015
Debt Instrument [Line Items]
Junior subordinated notes issued to capital trusts	$ 23,692	$ 23,587
Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary trust, face value	24,743	24,743
Junior subordinated notes issued to capital trusts	23,692	23,587
Junior Subordinated Debt [Member] | CBI Capital Trust II
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary trust, face value	7,217	7,217
Junior subordinated notes issued to capital trusts	$ 6,614	$ 6,552
Interest rate	4.46%	4.01%
Debt instrument, maturity date	Mar. 15, 2038	Mar. 15, 2038
Debt instrument, earliest call date	Mar. 15, 2013	Mar. 15, 2013
Junior Subordinated Debt [Member] | CBI Capital Trust II | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Description of variable rate basis	Three-month LIBOR
Basis spread on variable rate	3.50%
Junior Subordinated Debt [Member] | Barron Investment Capital Trust 1
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary trust, face value	$ 2,062	$ 2,062
Junior subordinated notes issued to capital trusts	$ 1,614	$ 1,571
Interest rate	3.15%	2.74%
Debt instrument, maturity date	Sep. 23, 2036	Sep. 23, 2036
Debt instrument, earliest call date	Sep. 23, 2011	Sep. 23, 2011
Junior Subordinated Debt [Member] | Barron Investment Capital Trust 1 | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Description of variable rate basis	Three-month LIBOR
Basis spread on variable rate	2.15%
Junior Subordinated Debt [Member] | MidWestOne Statutory Trust II
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary trust, face value	$ 15,464	$ 15,464
Junior subordinated notes issued to capital trusts	$ 15,464	$ 15,464
Interest rate	2.55%	2.10%
Debt instrument, maturity date	Dec. 15, 2037	Dec. 15, 2037
Debt instrument, earliest call date	Dec. 15, 2012	Dec. 15, 2012
Junior Subordinated Debt [Member] | MidWestOne Statutory Trust II | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Description of variable rate basis	Three-month LIBOR
Basis spread on variable rate	1.59%
Subordinated Debt [Member] | 1907 EJF Fund, LTD
Debt Instrument [Line Items]
Redemption date of subordinated note		Jun. 23, 2015
Central Bancshares, Inc.
Debt Instrument [Line Items]
Subordinated note assumed in merger		$ 12,669	$ 12,669
Central Bancshares, Inc. | Subordinated Debt [Member] | 1907 EJF Fund, LTD
Debt Instrument [Line Items]
Subordinated note assumed in merger			$ 12,300
Maximum
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary, deferral period	5 years

Long-Term Borrowings (Details)

Long-Term Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2015	Apr. 30, 2015
Debt Instrument [Line Items]
Long-term debt, excluding subordinated debt	$ 132,500	$ 109,500
Long-term debt, excluding subordinated debt, weighted average interest rate	1.69%	1.75%
Federal Home Loan Bank Advances
Debt Instrument [Line Items]
Long-term debt	$ 115,000	$ 87,000
Long-term debt, weighted average interest rate	1.56%	1.64%
Federal Home Loan, Bank advances general debt obligations, disclosures maximum borrowing capacity as percentage of total assets	35.00%
Notes Payable to Banks
Debt Instrument [Line Items]
Long-term debt	$ 17,500	$ 22,500
Long-term debt, weighted average interest rate	2.52%	2.17%
Debt instrument, issuance date	Apr. 30, 2015
Debt instrument, face amount				$ 35,000
Long-term debt, amount advanced			$ 25,000
Debt instrument, maturity date	Jun. 30, 2020
Debt instrument, frequency of periodic payment	quarterly
Debt instrument, date of first required payment	Sep. 30, 2015

Long-Term Borrowings Federal Ho

Long-Term Borrowings Federal Home Loan Bank Advances (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Due in next twelve months	$ 30,000	$ 22,000
Due in year two	19,000	10,000
Due in year three	27,000	19,000
Due in year four	32,000	17,000
Due in year five	7,000	12,000
Due after year five		7,000
Total Federal Home Loan Bank borrowings	$ 115,000	$ 87,000
Minimum
Debt Instrument [Line Items]
Average interest rate of amounts due within one year	0.79%	0.50%
Average interest rate, due in one to two years	1.30%	1.09%
Average interest rate, due in two to three years	1.42%	1.30%
Average interest rate, due in three to four years	1.52%	1.42%
Average interest rate, due in four to five years	1.93%	1.52%
Average interest rate, due after five years		1.93%
Maximum
Debt Instrument [Line Items]
Average interest rate of amounts due within one year	2.78%	2.46%
Average interest rate, due in one to two years	1.60%	2.78%
Average interest rate, due in two to three years	1.85%	1.83%
Average interest rate, due in three to four years	2.25%	1.85%
Average interest rate, due in four to five years	1.93%	2.25%
Average interest rate, due after five years		1.93%

Income Tax Components (Details)

Income Tax Components (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current Federal tax expense									$ 7,410	$ 6,147	$ 3,573
Current State tax expense									2,303	372	956
Deferred income tax expense (benefit)									(2,853)	1,300	2,502
Total income tax provision	$ 532	$ 2,629	$ 1,794	$ 1,905	$ 1,429	$ 2,121	$ 2,594	$ 1,675	$ 6,860	$ 7,819	$ 7,031

Income Tax Reconciliation (Deta

Income Tax Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Expected provision, amount									$ 9,538	$ 11,528	$ 8,943
Tax-exempt interest, amount									(3,011)	(2,817)	(2,520)
Bank-owned life insurance, amount									(477)	(438)	(385)
State income taxes, net of federal income tax benefit, amount									1,257	333	798
Non-deductible acquisition expenses									83	691	261
General business credits									(537)	(1,225)	0
Other, amount									7	(253)	(66)
Total income tax provision	$ 532	$ 2,629	$ 1,794	$ 1,905	$ 1,429	$ 2,121	$ 2,594	$ 1,675	$ 6,860	$ 7,819	$ 7,031
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Expected provision, percent									35.00%	35.00%	35.00%
Tax-exempt interest, percent									(11.00%)	(8.60%)	(9.90%)
Bank-owned life insurance, percent									(1.80%)	(1.30%)	(1.50%)
State income taxes, net of federal income tax benefit, percent									4.60%	1.00%	3.10%
Non-deductible acquisition expenses, percent									0.30%	2.10%	1.00%
General business credits									(2.00%)	(3.70%)	(0.00%)
Other, percent									0.10%	(0.80%)	(0.30%)
Effective income tax rate reconciliation, percent									25.20%	23.70%	27.40%

Deferred Tax Assets and Liabili

Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Tax Assets, Gross [Abstract]
Allowance for loan losses	$ 8,585	$ 7,449
Deferred compensation	1,982	1,909
Net operating losses (state net operating loss carryforwards)	3,838	3,560
Unrealized losses on investment securities	738	0
Other real estate owned	283	146
Other	3,012	1,934
Gross deferred tax assets	18,438	14,998
Deferred Tax Liabilities, Gross [Abstract]
Premises and equipment depreciation and amortization	4,092	3,658
Federal Home Loan Bank stock	137	133
Purchase accounting adjustments	2,352	2,717
Mortgage servicing rights	766	853
Prepaid expenses	289	194
Unrealized gains on investment securities	0	2,091
Deferred loan fees	225	261
Other	216	584
Gross deferred tax liabilities	8,077	10,491
Net deferred income tax asset	10,361	4,507
Valuation allowance	3,838	3,560
Net deferred tax asset	$ 6,523	$ 947

Income Taxes Textual References

Income Taxes Textual References (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Operating Loss Carryforwards [Line Items]
Unrecognized Tax Benefits	$ 0	$ 0
Earliest Tax Year
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards, Expiration Dates	Dec. 31, 2018
Latest Tax Year
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards, Expiration Dates	Dec. 31, 2037
Iowa
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	$ 47,800

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Employee Benefit Plans [Abstract]
Defined contribution plan, cost recognized	$ 1.3	$ 1.2	$ 0.7
Employee stock ownership plan (ESOP), compensation expense	0.8	1	0.5
Salary continuation plan cost recognized	0.4	0.4	0.3
Cash surrender value of life insurance, salary continuation plans	$ 16.4	$ 14.7	$ 14.3

Stock Compensation Plans (Detai

Stock Compensation Plans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, number of shares authorized	750,000
Share-based compensation, number of shares available for grant	431,828	460,757
Share-based compensation expense	$ 731,000	$ 634,000	$ 493,000
Share based compensation arrangement by share based payment award, number of shares per unit	1
Share-based Compensation Arrangement by Share-based Payment Award, Options, Intrinsic Value Cash Received and Tax Benefits Realized [Abstract]
Share-based compensation, cash received from exercise of stock options	$ 53,000
Share-based compensation, options exercises in period, total intrinsic value	26,000	119,000	109,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Share-based compensation, nonvested stock options, compensation cost not yet recognized	0
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 731,000	634,000	493,000
Share based compensation arrangement by share based payment award, award vesting rights percentage death disability or change in control	100.00%
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Share-based compensation, nonvested awards other than options, compensation cost not yet recognized	$ 1,205,000
Share-based compensation, nonvested awards, period for recognition of unrecognized compensation cost	2 years 6 months
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options Grant Date Fair Value [Abstract]
Share-based compensation, other than options, fair value of equity instruments vested in period	$ 983,000	703,000	792,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 0	$ 0	$ 0
Share-based compensation, award vesting period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Intrinsic Value Cash Received and Tax Benefits Realized [Abstract]
Share-based compensation, tax benefit from compensation expense	$ 5,000
2008 Equity Incentive Plan | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested at December 31, 2015	60,858
Granted	38,200
Vested	(26,133)
Forfeited	(6,875)
Nonvested at December 31, 2016	66,050	60,858
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Nonvested at December 31, 2015	$ 26.46
Granted	27.03
Vested	25.47
Forfeited	27.85
Nonvested at December 31, 2016	$ 27.04	$ 26.46
2008 Equity Incentive Plan | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, award vesting percentage per year	25.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at December 31, 2015	22,300
Granted	0	0	0
Exercised	(2,900)
Forfeited	0
Expired	(950)
Outstanding at December 31, 2016	18,450	22,300
Exercisable at December 31, 2016	18,450
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at December 31, 2015	$ 13.51
Granted	0
Exercised	18.25
Forfeited	0
Expired	20.08
Outstanding at December 31, 2016	12.42	$ 13.51
Exercisable at December 31, 2016	$ 12.42
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Share-based compensation, options outstanding weighted average remaining contractual term	1 year 9 months 3 days
Share-based compensation, options, exercisable weighted average remaining contractual term	1 year 9 months 3 days
Share-based compensation, options outstanding intrinsic value	$ 465,000
Share-based compensation options exercisable intrinsic value	$ 465,000
Management | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting period	4 years
Management | 2008 Equity Incentive Plan | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, award vesting percentage per year	25.00%
Director | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, award vesting period	1 year
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage	100.00%

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Net income	$ 3,870	$ 6,222	$ 4,755	$ 5,544	$ 8,238	$ 7,615	$ 4,469	$ 4,796	$ 20,391	$ 25,118	$ 18,522
Weighted average shares outstanding									11,430,087	10,362,929	8,405,284
Basic earnings per common share	$ 0.34	$ 0.54	$ 0.42	$ 0.49	$ 0.72	$ 0.67	$ 0.43	$ 0.57	$ 1.78	$ 2.42	$ 2.20
Weighted average shares outstanding, included all dilutive potential shares									11,456,324	10,391,323	8,433,296
Diluted earnings per common share	$ 0.34	$ 0.54	$ 0.42	$ 0.48	$ 0.72	$ 0.67	$ 0.42	$ 0.57	$ 1.78	$ 2.42	$ 2.19

Regulatory Capital Requireme102

Regulatory Capital Requirements and Restrictions on Subsidiary Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital	$ 280,396	$ 263,717
Tier one risk based capital	258,304	244,154
Common equity tier one capital	234,638	220,567
Tier one leverage capital	$ 258,304	$ 244,154
Total capital to risk weighted assets	11.65%	11.48%
Tier one risk based capital to risk weighted assets	10.73%	10.63%
Common equity tier one capital to risk weighted assets	9.75%	9.60%
Tier one leverage capital to average assets	8.75%	8.34%
Capital required for capital adequacy purposes	$ 207,661	$ 183,718
Tier one risk based capital required for capital adequacy purposes	159,508	137,789
Common equity tier one capital required for capital adequacy purposes	123,393	103,342
Tier one capital required for capital adequacy purposes	$ 118,040	$ 117,123
Capital required for capital adequacy purposes to risk weighted assets	8.625%	8.00%
Tier one risk based capital required for capital adequacy purposes to risk weighted assets	6.625%	6.00%
Common equity tier one capital required for capital adequacy purposes to risk weighted assets	5.125%	4.50%
Tier one leverage capital required for capital adequacy purposes to average assets	4.00%	4.00%
Policy guideline, minimum tier one capital to total assets	8.00%
Policy guideline, minimum capital to risk weighted assets	10.00%
Required cash reserve	$ 6,800	$ 2,000
MidWestOne Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital	286,959	171,583
Tier one risk based capital	264,871	154,726
Common equity tier one capital	264,871	154,726
Tier one leverage capital	$ 264,871	$ 154,726
Total capital to risk weighted assets	11.96%	12.53%
Tier one risk based capital to risk weighted assets	11.04%	11.30%
Common equity tier one capital to risk weighted assets	11.04%	11.30%
Tier one leverage capital to average assets	8.98%	8.90%
Capital required for capital adequacy purposes	$ 206,892	$ 109,578
Tier one risk based capital required for capital adequacy purposes	158,917	82,183
Common equity tier one capital required for capital adequacy purposes	122,936	61,638
Tier one capital required for capital adequacy purposes	$ 118,000	$ 69,501
Capital required for capital adequacy purposes to risk weighted assets	8.625%	8.00%
Tier one risk based capital required for capital adequacy purposes to risk weighted assets	6.625%	6.00%
Common equity tier one capital required for capital adequacy purposes to risk weighted assets	5.125%	4.50%
Tier one leverage capital required for capital adequacy purposes to average assets	4.00%	4.00%
Capital required to be well capitalized	$ 239,875	$ 136,972
Tier one risk based capital required to be well capitalized	191,900	109,578
Common equity tier one risk based capital required to be well capitalized	155,919	89,032
Tier one leverage capital required to be well capitalized	$ 147,500	$ 86,876
Capital required to be well capitalized to risk weighted assets	10.00%	10.00%
Tier one risk based capital required to be well capitalized to risk weighted assets	8.00%	8.00%
Common equity tier one risk based capital required to be well capitalized to Rrsk weighted assets	6.50%	6.50%
Tier one leverage capital required to be well capitalized to average assets	5.00%	5.00%
Central Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital		$ 102,718
Tier one risk based capital		100,017
Common equity tier one capital		100,017
Tier one leverage capital		$ 100,017
Total capital to risk weighted assets		11.14%
Tier one risk based capital to risk weighted assets		10.84%
Common equity tier one capital to risk weighted assets		10.84%
Tier one leverage capital to average assets		8.44%
Capital required for capital adequacy purposes		$ 73,792
Tier one risk based capital required for capital adequacy purposes		55,344
Common equity tier one capital required for capital adequacy purposes		41,508
Tier one capital required for capital adequacy purposes		$ 47,412
Capital required for capital adequacy purposes to risk weighted assets		8.00%
Tier one risk based capital required for capital adequacy purposes to risk weighted assets		6.00%
Common equity tier one capital required for capital adequacy purposes to risk weighted assets		4.50%
Tier one leverage capital required for capital adequacy purposes to average assets		4.00%
Capital required to be well capitalized		$ 92,240
Tier one risk based capital required to be well capitalized		73,792
Common equity tier one risk based capital required to be well capitalized		59,956
Tier one leverage capital required to be well capitalized		$ 59,265
Capital required to be well capitalized to risk weighted assets		10.00%
Tier one risk based capital required to be well capitalized to risk weighted assets		8.00%
Common equity tier one risk based capital required to be well capitalized to Rrsk weighted assets		6.50%
Tier one leverage capital required to be well capitalized to average assets		5.00%

Commitments and Contingencie103

Commitments and Contingencies (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Other Commitments [Line Items]
Other commitment	$ 487,286	$ 437,260
Standby letters of credit
Other Commitments [Line Items]
Loss contingency accrual	200	100
Commitments to extend credit
Other Commitments [Line Items]
Other commitment	473,725	417,927
Standby letters of credit
Other Commitments [Line Items]
Other commitment	9,320	16,146
Commitments to sell loans
Other Commitments [Line Items]
Other commitment	$ 4,241	$ 3,187

Commitments and Contingencies T

Commitments and Contingencies Textual References (Details) - Credit Concentration Risk $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Loans Concentration | Agricultural Related Loan Financing Receivable
Concentration Risk [Line Items]
Concentration risk, percentage	10.00%
Loans Concentration | Commercial Real Estate Portfolio Segment
Concentration Risk [Line Items]
Concentration risk, percentage	72.00%
Investment Securities | State and political subdivisions
Concentration Risk [Line Items]
Concentration risk, credit risk, financial instrument, maximum exposure	$ 5
Investment Securities | IOWA | State and political subdivisions
Concentration Risk [Line Items]
Concentration risk, credit risk, financial instrument, maximum exposure	155.6
Investment Securities | MINNESOTA | State and political subdivisions
Concentration Risk [Line Items]
Concentration risk, credit risk, financial instrument, maximum exposure	$ 57.5

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Loans and Leases Receivable, Related Parties [Roll Forward]
Balance, beginning	$ 10,247	$ 11,655
Net decrease due to change in related parties	(906)	(284)
Advances	2,834	3,919
Collections	(1,319)	(5,043)
Balance, ending	$ 10,856	$ 10,247

Related Party Transactions Text

Related Party Transactions Textual References (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
Related party deposit liabilities	$ 8,300,000	$ 8,500,000
Director | Purchase of Architectural Services
Related Party Transaction [Line Items]
Amount of related party transaction	$ 77,000	$ 254,000

Fair Value Financial Assets and

Fair Value Financial Assets and Liabilities Measured on a Recurring Basis (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)count	Dec. 31, 2015USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	$ 477,518	$ 427,241
Level 1 to Level 2 transfers of assets, fair value, amount	0	0
Level 2 to Level 1 transfers of assets, fair value, amount	0	0
Transfer of assets, fair value, to (from) Level 3, amount	$ 0	0
Changes in fair value measurements valuation techniques	0
Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	$ 1,267	1,262
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	476,251	425,979
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	477,518	427,241
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	1,267	1,262
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	$ 476,251	425,979
Debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Sample size used to validate pricing service results | count	30
Available for sale	$ 476,251	425,979
Debt securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	476,251	425,979
Debt securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	476,251	425,979
US Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale		6,910
US Treasury securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale		6,910
US Treasury securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale		6,910
U.S. Government agencies and corporations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	5,905	26,653
U.S. Government agencies and corporations | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	5,905	26,653
U.S. Government agencies and corporations | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	5,905	26,653
State and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	165,272	183,384
State and political subdivisions | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	165,272	183,384
State and political subdivisions | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	165,272	183,384
Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	61,354	57,062
Mortgage-backed securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	61,354	57,062
Mortgage-backed securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	61,354	57,062
Collateralized mortgage obligations | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	171,267	106,404
Collateralized mortgage obligations | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	171,267	106,404
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	72,453	45,566
Corporate debt securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	72,453	45,566
Corporate debt securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	72,453	45,566
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	1,267	1,262
Equity securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	1,267	1,262
Equity securities | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	$ 1,267	$ 1,262

Fair Value Assets and Liabiliti

Fair Value Assets and Liabilities Measured on a Nonrecurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned	$ 2,097	$ 8,834
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	8,774	23,812
Other real estate owned	2,097	8,834
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	8,774	23,812
Other real estate owned	$ 2,097	$ 8,834

Fair Value of Financial Instrum

Fair Value of Financial Instruments (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Investment securities:
Available for sale	$ 477,518	$ 427,241
Held to maturity	168,392	118,423
Held to maturity, estimated fair value	164,792	118,234
Accrued interest receivable	13,871	13,736
Federal Home Loan Bank Stock	12,800	9,832
Deposits:
Non-interest-bearing demand	494,586	559,586
Interest-bearing checking	1,136,282	1,064,350
Savings	197,698	189,489
Accrued interest payable	$ 1,472	1,507
Federal Home Loan Bank stock, redemption price, per share	$ 100
Carrying Amount
Financial assets:
Cash and cash equivalents	$ 43,228	47,097
Investment securities:
Available for sale	477,518	427,241
Held to maturity	168,392	118,423
Total investment securities	645,910	545,664
Loans held for sale	4,241	3,187
Loans, net	2,143,293	2,132,515
Accrued interest receivable	13,871	13,736
Deposits:
Non-interest-bearing demand	494,586	559,586
Interest-bearing checking	1,136,282	1,064,350
Savings	197,698	189,489
Certificates of deposit under $100,000	326,832	348,268
Certificates of deposit $100,000 and over	325,050	301,828
Total deposits	2,480,448	2,463,521
Federal funds purchased and securities sold under agreements to repurchase	117,871	68,963
Federal Home Loan Bank borrowings	115,000	87,000
Junior subordinated notes issued to capital trusts	23,692	23,587
Long-term debt	17,500	22,500
Accrued interest payable	1,472	1,507
Estimated Fair Value
Financial assets:
Cash and cash equivalents	43,228	47,097
Investment securities:
Available for sale	477,518	427,241
Held to maturity, estimated fair value	164,792	118,234
Total investment securities	642,310	545,475
Loans held for sale	4,286	3,262
Loans, net	2,138,252	2,132,009
Accrued interest receivable	13,871	13,736
Federal Home Loan Bank Stock	12,800	9,832
Deposits:
Non-interest-bearing demand	494,586	559,586
Interest-bearing checking	1,136,282	1,064,350
Savings	197,698	189,489
Certificates of deposit under $100,000	324,978	346,875
Certificates of deposit $100,000 and over	324,060	301,521
Total deposits	2,477,604	2,461,821
Federal funds purchased and securities sold under agreements to repurchase	117,871	68,963
Federal Home Loan Bank borrowings	114,590	86,817
Junior subordinated notes issued to capital trusts	19,248	18,611
Long-term debt	17,500	22,500
Accrued interest payable	1,472	1,507
Fair Value, Inputs, Level 1
Financial assets:
Cash and cash equivalents	43,228	47,097
Investment securities:
Available for sale	1,267	1,262
Total investment securities	1,267	1,262
Accrued interest receivable	13,871	13,736
Deposits:
Non-interest-bearing demand	494,586	559,586
Interest-bearing checking	1,136,282	1,064,350
Savings	197,698	189,489
Total deposits	1,828,566	1,813,425
Federal funds purchased and securities sold under agreements to repurchase	117,871	68,963
Accrued interest payable	1,472	1,507
Fair Value, Inputs, Level 2
Investment securities:
Available for sale	476,251	425,979
Held to maturity, estimated fair value	164,792	118,234
Total investment securities	641,043	544,213
Loans, net	2,138,252	2,132,009
Federal Home Loan Bank Stock	12,800	9,832
Deposits:
Certificates of deposit under $100,000	324,978	346,875
Certificates of deposit $100,000 and over	324,060	301,521
Total deposits	649,038	648,396
Federal Home Loan Bank borrowings	114,590	86,817
Junior subordinated notes issued to capital trusts	19,248	18,611
Long-term debt	17,500	22,500
Fair Value, Inputs, Level 3
Investment securities:
Loans held for sale	4,286	3,262
Loans, net

Branch Sales (Details)

Branch Sales (Details) - Disposal Group, Disposed of by Sale, Not Discontinued Operations - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Central Bank | Rice Lake and Barron Wisconsin Branch [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, deposits	$ 27.6
Disposal group, loans	14.2
MidWestOne Bank | Ottumwa Iowa Branch
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, deposits		$ 33
Disposal group, loans		17.1
MidWestOne Bank | Davenport Iowa Branch [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, deposits	12
Disposal group, loans	33
Other Gain (Loss) [Member] | Central Bank | Rice Lake and Barron Wisconsin Branch [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, gain on disposal	0.7
Other Gain (Loss) [Member] | MidWestOne Bank | Ottumwa Iowa Branch
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, gain on disposal		$ 0.7
Other Gain (Loss) [Member] | MidWestOne Bank | Davenport Iowa Branch [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal group, gain on disposal	$ 0.7

Parent Company Only Balance She

Parent Company Only Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assets:
Available for sale	$ 477,518	$ 427,241
Held to maturity	168,392	118,423
Income tax receivable	0	1,079
Deferred income taxes	6,523	947
Other assets	18,313	21,809
Total assets	3,079,575	2,979,975
Liabilities:
Junior subordinated notes issued to capital trusts	23,692	23,587
Long-term debt	17,500	22,500
Other liabilities	12,956	11,587
Total liabilities	2,774,119	2,683,797
Shareholders’ equity:
Capital stock, preferred	0	0
Capital stock, common	11,713	11,713
Additional paid-in capital	163,667	163,487
Treasury stock	(5,766)	(6,331)
Retained earnings	136,975	123,901
Accumulated other comprehensive income	(1,133)	3,408
Total shareholders’ equity	305,456	296,178	$ 192,731	$ 178,016
Total liabilities and shareholders’ equity	3,079,575	2,979,975
Parent Company
Assets:
Cash	2,621	4,489	$ 5,942	$ 5,781
Investment in subsidiaries	336,937	331,612
Available for sale	326	300
Held to maturity	743	743
Income tax receivable	1,479	571
Other assets	4,947	4,976
Total assets	347,053	342,691
Liabilities:
Junior subordinated notes issued to capital trusts	23,692	23,587
Long-term debt	17,500	22,500
Deferred income taxes	84	113
Other liabilities	321	313
Total liabilities	41,597	46,513
Shareholders’ equity:
Capital stock, preferred	0	0
Capital stock, common	11,713	11,713
Additional paid-in capital	163,667	163,487
Treasury stock	(5,766)	(6,331)
Retained earnings	136,975	123,901
Accumulated other comprehensive income	(1,133)	3,408
Total shareholders’ equity	305,456	296,178
Total liabilities and shareholders’ equity	$ 347,053	$ 342,691

Parent Company Only Statements

Parent Company Only Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Interest and discount on loan pool participations										$ 798	$ 1,516
Investment securities gains									$ 464	1,011	1,227
Operating expenses	$ (21,106)	$ (20,439)	$ (22,815)	$ (23,446)	$ (21,809)	$ (20,342)	$ (19,846)	$ (11,179)	(87,806)	(73,176)	(43,413)
Income tax expense (benefit)	532	2,629	1,794	1,905	1,429	2,121	2,594	1,675	6,860	7,819	7,031
Net income	$ 3,870	$ 6,222	$ 4,755	$ 5,544	$ 8,238	$ 7,615	$ 4,469	$ 4,796	20,391	25,118	18,522
Parent Company
Condensed Financial Statements, Captions [Line Items]
Dividends from subsidiaries									12,508	53,511	8,500
Interest income and dividends on investment securities									31	30	49
Interest and discount on loan pool participations									0	(69)	(293)
Investment securities gains									0	188	0
Loss on sale of loan pool participations									0	(455)	0
Interest on debt									(1,305)	(1,135)	(281)
Operating expenses									(1,966)	(5,233)	(2,351)
Income before income taxes and equity in subsidiaries’ undistributed income									9,268	46,837	5,624
Income tax expense (benefit)									(1,245)	(1,951)	(807)
Income before equity in subsidiaries’ undistributed income									10,513	48,788	6,431
Equity in subsidiaries’ undistributed income									9,878	(23,670)	12,091
Net income									$ 20,391	$ 25,118	$ 18,522

Parent Company Only Statemen113

Parent Company Only Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income	$ 3,870	$ 6,222	$ 4,755	$ 5,544	$ 8,238	$ 7,615	$ 4,469	$ 4,796	$ 20,391	$ 25,118	$ 18,522
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income taxes									(2,853)	1,300	2,502
Investment securities gain									(464)	(1,011)	(1,227)
Stock based compensation									731	634	493
(Increase) decrease in other assets									3,496	3,037	485
Net cash provided by operating activities									38,184	32,708	23,264
Cash flows from investing activities
Proceeds from sales of available for sale securities									23,381	116,829	33,457
Purchase of available for sale securities									(166,618)	(25,424)	(67,892)
Proceeds from maturities and calls of held to maturity securities									12,080	4,669	1,147
Loan participation pools, net									0	19,332	6,201
Net cash acquired in business combination									0	(35,596)	0
Net cash provided by (used in) investing activities									(123,585)	5,013	(47,436)
Cash flows from financing activities:
Repurchase of common stock									0	0	(3,987)
Redemption of subordinated note									0	(12,669)	0
Proceeds from Issuance of Long-term Debt									0	25,000	0
Payments on long-term debt									(5,000)	(2,500)	0
Issuance of common stock, net of expenses									0	7,900	0
Dividends paid									(7,317)	(6,344)	(4,868)
Net cash provided by (used in) financing activities									81,532	(14,033)	22,691
Net increase (decrease) in cash and cash equivalents									(3,869)	23,688	(1,481)
Parent Company
Cash flows from operating activities:
Net income									20,391	25,118	18,522
Adjustments to reconcile net income to net cash provided by operating activities:
Undistributed (earnings) loss of subsidiaries, net of dividends and distributions									(9,878)	23,670	(12,091)
Amortization of premium on junior subordinated notes issued to capital trusts									105	73	0
Deferred income taxes									(35)	617	330
Investment securities gain									0	(188)	0
Stock based compensation									731	634	493
(Increase) decrease in other assets									(879)	518	(488)
Increase (decrease) in other liabilities									8	(907)	550
Net cash provided by operating activities									10,443	49,535	7,316
Cash flows from investing activities
Proceeds from sales of available for sale securities									1	1,173	2
Purchase of available for sale securities									(9)	(14)	(29)
Proceeds from maturities and calls of held to maturity securities										246
Loan participation pools, net									0	1,964	1,445
Net cash acquired in business combination										(62,902)
Investment in subsidiary - Central Bank										(3,000)
Net cash provided by (used in) investing activities									(8)	(62,533)	1,418
Cash flows from financing activities:
Stock options exercised									14	158	282
Repurchase of common stock									0	0	(3,987)
Redemption of subordinated note										(12,669)
Proceeds from Issuance of Long-term Debt									0	25,000	0
Payments on long-term debt									(5,000)	(2,500)
Issuance of common stock, net of expenses									0	7,900	0
Dividends paid									(7,317)	(6,344)	(4,868)
Net cash provided by (used in) financing activities									(12,303)	11,545	(8,573)
Net increase (decrease) in cash and cash equivalents									(1,868)	(1,453)	161
Cash Balance:
Beginning				$ 4,489				$ 5,942	4,489	5,942	5,781
Ending	$ 2,621				$ 4,489				$ 2,621	$ 4,489	$ 5,942

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event [Member] - Common Stock	Jan. 25, 2017$ / shares
Subsequent Event [Line Items]
Dividends Payable, Amount Per Share	$ 0.165
Dividends Payable, Date to be Paid	Mar. 15, 2017
Dividends Payable, Date of Record	Mar. 1, 2017

Quarterly Results of Operati115

Quarterly Results of Operations (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest income	$ 27,914	$ 27,891	$ 28,038	$ 28,485	$ 29,044	$ 29,989	$ 25,185	$ 16,482	$ 112,328	$ 100,700	$ 64,404
Interest expense	3,384	3,310	3,098	2,930	2,716	3,230	2,462	2,240	12,722	10,648	9,551
Net interest income	24,530	24,581	24,940	25,555	26,328	26,759	22,723	14,242	99,606	90,052	54,853
Provision for loan losses	4,742	1,005	1,171	1,065	1,490	2,141	901	600	7,983	5,132	1,200
Noninterest income	5,720	5,714	5,595	6,405	6,638	5,460	5,087	4,008	23,434	21,193	15,313
Noninterest expense	21,106	20,439	22,815	23,446	21,809	20,342	19,846	11,179	87,806	73,176	43,413
Income before income tax expense	4,402	8,851	6,549	7,449	9,667	9,736	7,063	6,471	27,251	32,937	25,553
Income tax expense	532	2,629	1,794	1,905	1,429	2,121	2,594	1,675	6,860	7,819	7,031
Net income	$ 3,870	$ 6,222	$ 4,755	$ 5,544	$ 8,238	$ 7,615	$ 4,469	$ 4,796	$ 20,391	$ 25,118	$ 18,522
Basic earnings per common share	$ 0.34	$ 0.54	$ 0.42	$ 0.49	$ 0.72	$ 0.67	$ 0.43	$ 0.57	$ 1.78	$ 2.42	$ 2.20
Diluted earnings per common share	$ 0.34	$ 0.54	$ 0.42	$ 0.48	$ 0.72	$ 0.67	$ 0.42	$ 0.57	$ 1.78	$ 2.42	$ 2.19