MidWestOne Financial (MOFG) 10-Q 3 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	May 01, 2018
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
Trading Symbol	MOFG
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		12,215,342

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
ASSETS
Cash and due from banks	$ 39,929	$ 44,818
Interest-bearing deposits in banks	2,467	5,474
Federal funds sold	0	680
Cash and cash equivalents	42,396	50,972
Investment securities:
Equity securities	2,815
Equity securities		2,336
Available for sale debt securities	446,087	445,324
Held to maturity debt securities (fair value of $190,593 as of March 31, 2018 and $194,343 as of December 31, 2017)	194,617	195,619
Loans held for sale	870	856
Loans and leases receivable, gross	2,326,158	2,286,695
Less: Allowance for loan losses	(29,671)	(28,059)
Net loans	2,296,487	2,258,636
Premises and equipment, net	77,552	75,969
Accrued interest receivable	13,337	14,732
Goodwill	64,654	64,654
Other intangible assets, net	11,389	12,046
Bank-owned life insurance	59,812	59,831
Other real estate owned	1,001	2,010
Deferred income taxes	7,866	6,525
Other assets	22,759	22,761
Total assets	3,241,642	3,212,271
Deposits:
Non-interest-bearing demand	450,168	461,969
Interest-bearing checking	1,240,208	1,228,112
Savings	215,940	213,430
Certificates of deposit under $100,000	332,727	324,681
Certificates of deposit $100,000 and over	392,878	377,127
Total deposits	2,631,921	2,605,319
Federal funds purchased	25,573	1,000
Securities sold under agreements to repurchase	67,738	96,229
Federal Home Loan Bank borrowings	123,000	115,000
Junior subordinated notes issued to capital trusts	23,817	23,793
Long-term debt	11,250	12,500
Deferred compensation liability	5,258	5,199
Accrued interest payable	1,459	1,428
Other liabilities	10,249	11,499
Total liabilities	2,900,265	2,871,967
Shareholders' equity:
Preferred stock, no par value; authorized 500,000 shares; no shares issued and outstanding at March 31, 2018 and December 31, 2017	0	0
Common stock, $1.00 par value; authorized 30,000,000 shares at March 31, 2018 and December 31, 2017; issued 12,463,481 shares at March 31, 2018 and December 31, 2017; outstanding 12,214,942 shares at March 31, 2018 and 12,219,611 shares at December 31, 2017	12,463	12,463
Additional paid-in capital	187,188	187,486
Treasury stock at cost, 248,539 shares as of March 31, 2018 and 243,870 shares as of December 31, 2017	(5,612)	(5,121)
Retained earnings	153,542	148,078
Accumulated other comprehensive income	(6,204)	(2,602)
Total shareholders' equity	341,377	340,304
Total liabilities and shareholders' equity	$ 3,241,642	$ 3,212,271

Consolidated Balance Sheets Par

Consolidated Balance Sheets Parenthetical - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Held to maturity, estimated fair value	$ 190,593	$ 194,343
Shareholders' equity:
Preferred stock, par value	$ 0	$ 0
Preferred stock, shares authorized	500,000	500,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	30,000,000	30,000,000
Common stock, shares issued	12,463,481	12,463,481
Common stock, shares outstanding	12,214,942	12,219,611
Shares of Treasury stock	248,539	243,870

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Interest income:
Interest and fees on loans	$ 26,567	$ 24,279
Interest on bank deposits	8	5
Interest on investment securities:
Taxable securities	2,888	2,718
Tax-exempt securities	1,529	1,565
Total interest income	30,992	28,567
Interest expense:
Interest-bearing checking	1,085	798
Savings	63	51
Certificates of deposit under $100,000	995	859
Certificates of deposit $100,000 and over	1,393	917
Total interest expense on deposits	3,536	2,625
Interest on federal funds purchased	125	46
Interest on securities sold under agreements to repurchase	134	38
Interest on Federal Home Loan Bank borrowings	517	443
Interest on other borrowings	2	3
Interest on junior subordinated notes issued to capital trusts	258	221
Interest on long-term debt	107	110
Total interest expense	4,679	3,486
Net interest income	26,313	25,081
Provision for loan losses	1,850	1,041
Net interest income after provision for loan losses	24,463	24,040
Noninterest income:
Trust, investment and insurance fees	1,640	1,612
Service charges and fees on deposit accounts	1,168	1,283
Loan origination and servicing fees	941	802
Other service charges, commissions and fees	1,380	1,458
Bank-owned life insurance income	433	328
Gain on sale or call of available for sale debt securities	9	0
Net gain on sale or call of held to maturity securities	0	43
Loss on sale of premises and equipment	(1)	(2)
Other gain	102	13
Total noninterest income	5,672	5,537
Noninterest expense:
Salaries and employee benefits	12,371	11,884
Net occupancy and equipment expense	3,251	3,304
Professional fees	794	1,022
Data processing expense	688	711
FDIC insurance expense	319	367
Amortization of intangible assets	657	849
Other operating expense	2,278	2,198
Total noninterest expense	20,358	20,335
Income before income tax expense	9,777	9,242
Income tax expense	1,984	2,529
Net income	$ 7,793	$ 6,713
Share and per share information:
Ending number of shares outstanding	12,214,942	11,959,521
Average number of shares outstanding	12,222,690	11,505,687
Diluted average number of shares	12,241,714	11,555,356
Earnings per common share - basic	$ 0.64	$ 0.58
Earnings per common share - diluted	0.64	0.58
Dividends paid per common share	$ 0.195	$ 0.165

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income Statement - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net income	$ 7,793	$ 6,713
Other comprehensive income, available for sale debt securities:
Unrealized holding gains (losses) arising during period	(4,788)	1,567
Reclassification adjustment for gains included in net income	(9)	0
Income tax (expense) benefit	1,252	(616)
Other comprehensive income (loss) on available for sale debt securities	(3,545)	951
Other comprehensive income (loss), net of tax	(3,545)	951
Comprehensive income	4,248	7,664
AOCI Attributable to Parent [Member]
Net income	0	0
Other comprehensive income, available for sale debt securities:
Other comprehensive income (loss), net of tax	$ (3,545)	$ 951

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2016	$ 305,456	$ 0	$ 11,713	$ 163,667	$ (5,766)	$ 136,975	$ (1,133)
Net income	6,713	0	0	0	0	6,713	0
Issuance of common stock, net of expenses	16,142	0	500	15,642	0	0	0
Dividends paid on common stock	(1,891)	0	0	0	0	(1,891)	0
Stock options exercised	47	0	0	(74)	121	0	0
Release/lapse of restriction on RSUs	(103)	0	0	(420)	317	0	0
Stock compensation	199	0	0	199	0	0
Other comprehensive income (loss), net of tax	951	0	0	0	0	0	951
Balance at Mar. 31, 2017	327,514	0	12,213	179,014	(5,328)	141,797	(182)
Balance at Dec. 31, 2017	340,304	0	12,463	187,486	(5,121)	148,078	(2,602)
Net income	7,793	0	0	0	0	7,793	0
Dividends paid on common stock	(2,386)	0	0	0	0	(2,386)	0
Stock options exercised	136	0	0	(68)	204	0	0
Release/lapse of restriction on RSUs	(80)	0	0	(467)	387	0	0
Repurchase of common stock	(1,082)				(1,082)
Stock compensation	237	0	0	237	0	0	0
ASU 2016-01, reclassification from AOCI to Retained Earnings, unrealized gain on equity securities	0	0	0	0	0	57	(57)
Other comprehensive income (loss), net of tax	(3,545)	0	0	0	0	0	(3,545)
Balance at Mar. 31, 2018	$ 341,377	$ 0	$ 12,463	$ 187,188	$ (5,612)	$ 153,542	$ (6,204)

Consolidated Statements of Sha7

Consolidated Statements of Shareholders' Equity Parenthetical - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Dividends paid on common stock (per share)	$ 0.195	$ 0.165
Additional Paid-in Capital
Expenses incurred in issuance of common stock	$ 0	$ 983
Common Stock
Issuance of common stock (shares)	0	500,000
Stock options exercised (shares)	9,700	5,800
Release/lapse of restriction on RSUs (shares)	22,200	20,200
Common Stock
Repurchase of common stock (shares)	33,998	0

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net income	$ 7,793	$ 6,713
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	1,850	1,041
Depreciation, amortization and accretion	1,034	1,040
Amortization of other intangibles	657	849
Amortization of premiums and discounts on investment securities, net	(244)	(373)
Loss on sale of premises and equipment	1	2
Deferred income taxes	89	289
Excess tax benefit from share-based award activity	0	(75)
Stock-based compensation	237	199
Net losses on equity securities	24	0
Net gain on sale or call of available for sale debt securities	(9)	0
Net gain on sale or call of held to maturity securities	0	(43)
Net gain on sale of other real estate owned	(93)	(19)
Net gain on sale of loans held for sale	(253)	(323)
Writedown of other real estate owned	5	23
Origination of loans held for sale	12,916	18,770
Proceeds from sales of loans held for sale	13,155	22,953
Decrease in accrued interest receivable	1,395	1,175
Increase in cash surrender value of bank-owned life insurance	(433)	(328)
Decrease in other assets	2	784
Increase (decrease) in deferred compensation liability	59	20
Increase (decrease) in accrued interest payable, accounts payable, accrued expenses, and other liabilities	(1,219)	2,921
Net cash provided by operating activities	11,444	18,246
Cash flows from investing activities:
Purchases of equity securities		(1,002)
Purchases of equity securities	503
Proceeds from sales of available for sale securities	496
Proceeds from maturities and calls of available for sale securities	13,546	15,005
Purchases of available for sale securities	(19,770)	(6,811)
Proceeds from sales of held to maturity securities	0	1,153
Proceeds from maturities and calls of held to maturity securities	1,488	1,047
Purchases of held to maturity securities	(553)	(8,474)
Net increase in loans	(40,065)	(672)
Purchases of premises and equipment	(2,594)	(1,004)
Proceeds from sale of other real estate owned	1,461	494
Proceeds of principal and earnings from bank-owned life insurance	452	0
Net cash used in investing activities	(46,042)	(264)
Cash flows from financing activities:
Net increase in deposits	26,602	50,445
Increase (decrease) in federal funds purchased	24,573	(35,684)
Decrease in securities sold under agreements to repurchase	(28,491)	(14,596)
Proceeds from Federal Home Loan Bank borrowings	35,000	50,000
Repayment of Federal Home Loan Bank borrowings	(27,000)	(70,000)
Proceeds from stock options exercised	135	123
Excess tax benefit from share-based award activity	0	75
Taxes paid relating to net share settlement of equity awards	(79)	(104)
Payments on long-term debt	(1,250)	(1,250)
Dividends paid	(2,386)	(1,891)
Proceeds from issuance of common stock	0	17,125
Payments of stock issuance costs	0	(983)
Repurchase of common stock	(1,082)	0
Net cash provided by (used in) financing activities	26,022	(6,740)
Net increase (decrease) in cash and cash equivalents	(8,576)	11,242
Cash and cash equivalents at beginning of period	50,972	43,228
Cash and cash equivalents at end of period	42,396	54,470
Supplemental disclosures of cash flow information:
Cash paid during the period for interest	4,648	3,553
Supplemental schedule of non-cash investing activities:
Transfer of loans to other real estate owned	364	97
Accounting Standards Update 2016-01
Supplemental schedule of non-cash investing activities:
Transfer due to adoption of ASU 2016-01, equity securities fair value adjustment, reclassification from AOCI to Retained Earnings, net of tax	$ 57	$ 0

Principles of Consolidation and

Principles of Consolidation and Presentation	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	Principles of Consolidation and Presentation MidWest One Financial Group, Inc. (the “Company,” which is also referred to herein as “we,” “our” or “us”) is an Iowa corporation incorporated in 1983, a bank holding company under the Bank Holding Company Act of 1956, as amended, and a financial holding company under the Gramm-Leach-Bliley Act of 1999. Our principal executive offices are located at 102 South Clinton Street, Iowa City, Iowa 52240. The Company owns all of the common stock of MidWest One Bank, an Iowa state non-member bank chartered in 1934 with its main office in Iowa City, Iowa (the “Bank”), and all of the common stock of MidWest One Insurance Services, Inc., Oskaloosa, Iowa. We operate primarily through MidWest One Bank, our bank subsidiary, and MidWest One Insurance Services, Inc., our wholly-owned subsidiary that operates an insurance agency business through six offices located in central and east-central Iowa. The accompanying unaudited consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and, therefore, do not include all the information and notes necessary for complete financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”). The information in this Quarterly Report on Form 10-Q is written with the presumption that the users of the interim financial statements have read or have access to the most recent Annual Report on Form 10-K of the Company, which contains the latest audited financial statements and notes thereto, together with Management’s Discussion and Analysis of Financial Condition and Results of Operations as of December 31, 2017 and for the year then ended. Management believes that the disclosures in this Form 10-Q are adequate to make the information presented not misleading. In the opinion of management, the accompanying consolidated financial statements contain all adjustments (consisting of only normal recurring accruals) necessary to present fairly the Company’s financial position as of March 31, 2018 and December 31, 2017 , and the results of operations and cash flows for the three months ended March 31, 2018 and 2017 . All significant intercompany accounts and transactions have been eliminated in consolidation. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect: (1) the reported amounts of assets and liabilities, (2) the disclosure of contingent assets and liabilities at the date of the financial statements, and (3) the reported amounts of revenues and expenses during the reporting period. These estimates are based on information available to management at the time the estimates are made. Actual results could differ from those estimates. The results for the three months ended March 31, 2018 may not be indicative of results for the year ending December 31, 2018 , or for any other period. All significant accounting policies followed in the preparation of the quarterly financial statements are disclosed in the Annual Report on Form 10-K for the year ended December 31, 2017 . In the consolidated statements of cash flows, cash and cash equivalents include cash and due from banks, interest-bearing deposits in banks, and federal funds sold. 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.

Effect of New Financial Account

Effect of New Financial Accounting Standards	3 Months Ended
	Mar. 31, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Description of New Accounting Pronouncements Not yet Adopted [Text Block]	Effect of New Financial Accounting Standards Accounting Guidance Adopted in 2018 In May 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contract with Customers (Topic 606). Subsequent to the issuance of ASU 2014-09, the FASB issued targeted updates to clarify specific implementation issues including ASU No. 2016-08, “Principal versus Agent Considerations (Reporting Revenue Gross versus Net),” ASU No. 2016-10, “I dentifying Performance Obligations and Licensing, ” ASU No. 2016-12, “ Narrow-Scope Improvements and Practical Expedients, ” and ASU No. 2016-20 “ Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers. ” For financial reporting purposes, the standard allows for either full retrospective adoption, meaning the standard is applied to all of the periods presented, or modified retrospective adoption, meaning the standard is applied only to the most current period presented in the financial statements with the cumulative effect of initially applying the standard recognized at the date of initial application. Since the guidance does not apply to revenue associated with financial instruments, including loans and securities that are accounted for under other GAAP, the new guidance did not have a material impact on revenue most closely associated with financial instruments, including interest income and expense. The Company completed its overall assessment of revenue streams and review of related contracts potentially affected by the ASU, including trust and asset management fees, service charges on deposit accounts, sales of other real estate, and debit card interchange fees. Based on this assessment, the Company concluded that ASU 2014-09 did not materially change the method in which the Company currently recognizes revenue for these revenue streams. The Company also completed its evaluation of certain costs related to these revenue streams to determine whether such costs should be presented as expenses or contra-revenue (i.e., gross vs. net). Based on its evaluation, the Company determined that ASU 2014-09 also did not materially change the method in which the Company currently recognizes costs for these revenue streams. The Company adopted this update on January 1, 2018, utilizing the modified retrospective transition method. Since there was no net income impact upon adoption of the new guidance, a cumulative effect adjustment to opening retained earnings was not deemed necessary. See Note 14 “Revenue Recognition” for more information. 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 affect 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) require changes to current methodologies of determining these vales, 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. The Company adopted this update on January 1, 2018. With the elimination of the classification of available for sale equity securities, the net unrealized gain or loss on these securities that had been included in accumulated other comprehensive income at December 31, 2017, in the amount of $57,000 , has been transferred to retained earnings, as shown in the Consolidated Statement of Shareholders’ Equity. Changes in the fair value of equity securities with readily determinable fair values are now reflected in the noninterest income portion of the Consolidated Statements of Operations, in the other gains (losses) line item. In accordance with the ASU requirements, the Company measured the fair value of its loan portfolio as of March 31, 2018 using an exit price notion. See Note 13. “Estimated Fair Value of Financial Instruments and Fair Value Measurements” to our consolidated financial statements. Accounting Guidance Pending Adoption at March 31, 2018 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 has several lease agreements, such as branch locations, which are currently considered operating leases, and therefore not recognized on the Company’s consolidated balance sheets. The Company expects the new guidance will require these lease agreements to now be recognized on the consolidated balance sheets as right-of-use assets and a corresponding lease liability. However, the Company continues to evaluate the extent of the potential impact the new guidance will have on the Company’s consolidated financial statements and the availability of outside vendor products to assist in the implementation, and does not expect to early adopt the standard. 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 AFS) 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, and is expected to increase the allowance for loan losses upon adoption. The Company has formed a working group to evaluate the impact of the standard’s adoption on the Company’s consolidated financial statements, and has completed viewing demonstrations of the capabilities of outside vendor software systems, and is currently evaluating the ability of these systems to meet the processing necessary to support the data collection, retention, and disclosure requirements of the Company in implementation of the new standard.

Investment Securities

Investment Securities	3 Months Ended
	Mar. 31, 2018
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: As of March 31, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) U.S. Government agencies and corporations $ 15,678 $ — $ 279 $ 15,399 State and political subdivisions 146,386 1,663 523 147,526 Mortgage-backed securities 48,065 147 952 47,260 Collateralized mortgage obligations 178,068 13 7,276 170,805 Corporate debt securities 66,285 25 1,213 65,097 Total $ 454,482 $ 1,848 $ 10,243 $ 446,087 As of December 31, 2017 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) U.S. Government agencies and corporations $ 15,716 $ — $ 90 $ 15,626 State and political subdivisions 139,561 2,475 197 141,839 Mortgage-backed securities 48,744 181 428 48,497 Collateralized mortgage obligations 173,339 29 5,172 168,196 Corporate debt securities 71,562 31 427 71,166 Total debt securities 448,922 2,716 6,314 445,324 Other equity securities 2,268 124 56 2,336 Total $ 451,190 $ 2,840 $ 6,370 $ 447,660 The amortized cost and fair value of investment debt securities held to maturity, with gross unrealized gains and losses, are as follows: As of March 31, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) U.S. Government agencies and corporations $ 10,047 $ — $ 278 $ 9,769 State and political subdivisions 126,356 315 3,089 123,582 Mortgage-backed securities 1,882 2 45 1,839 Collateralized mortgage obligations 21,204 — 932 20,272 Corporate debt securities 35,128 504 501 35,131 Total $ 194,617 $ 821 $ 4,845 $ 190,593 As of December 31, 2017 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) U.S. Government agencies and corporations $ 10,049 $ — $ — $ 10,049 State and political subdivisions 126,413 804 1,631 125,586 Mortgage-backed securities 1,906 4 13 1,897 Collateralized mortgage obligations 22,115 — 707 21,408 Corporate debt securities 35,136 548 281 35,403 Total $ 195,619 $ 1,356 $ 2,632 $ 194,343 Investment securities with a carrying value of $238.2 million and $237.4 million at March 31, 2018 and December 31, 2017 , respectively, were pledged on public deposits, securities sold under agreements to repurchase and for other purposes, as required or permitted by law. As of March 31, 2018 , the Company owned $0.4 million of equity securities in banks and financial service-related companies, and $2.4 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. Prior to January 1, 2018, we accounted for our marketable equity securities at fair value with unrealized gains and losses recognized in accumulated other comprehensive income on the balance sheet. Realized gains and losses on marketable equity securities sold or impaired were recognized in noninterest income. Effective with the January 1, 2018 adoption of ASU 2016-01, both the realized and unrealized net gains and losses on equity securities are required to be recognized in the statement of operations. A breakdown between net realized and unrealized gains and losses is provided later in this financial statement footnote. These net changes are included in the other gains line item in the noninterest income section of the Consolidated Statements of Operations . 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 March 31, 2018 and December 31, 2017 . 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 March 31, 2018 and December 31, 2017 , aggregated by investment category and length of time that individual securities have been in a continuous loss position: As of March 31, 2018 Number of Securities Less than 12 Months 12 Months or More Total Available for Sale Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands, except number of securities) U.S. Government agencies and corporations 3 $ 15,399 $ 279 $ — $ — $ 15,399 $ 279 State and political subdivisions 72 33,470 452 2,757 71 36,227 523 Mortgage-backed securities 21 36,330 871 3,627 81 39,957 952 Collateralized mortgage obligations 41 47,328 1,010 117,834 6,266 165,162 7,276 Corporate debt securities 12 54,639 995 8,576 218 63,215 1,213 Total 149 $ 187,166 $ 3,607 $ 132,794 $ 6,636 $ 319,960 $ 10,243 As of December 31, 2017 Number of Securities Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands, except number of securities) U.S. Government agencies and corporations 3 $ 15,626 $ 90 $ — $ — $ 15,626 $ 90 State and political subdivisions 34 11,705 167 1,800 30 13,505 197 Mortgage-backed securities 20 37,964 359 3,961 69 41,925 428 Collateralized mortgage obligations 35 37,881 489 122,757 4,683 160,638 5,172 Corporate debt securities 12 55,340 298 8,778 129 64,118 427 Other equity securities 1 — — 1,944 56 1,944 56 Total 105 $ 158,516 $ 1,403 $ 139,240 $ 4,967 $ 297,756 $ 6,370 As of March 31, 2018 Number of Securities Less than 12 Months 12 Months or More Total Held to Maturity Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands, except number of securities) U.S. Government agencies and corporations 1 $ 9,769 $ 278 $ — $ — $ 9,769 $ 278 State and political subdivisions 227 52,946 1,212 25,191 1,877 78,137 3,089 Mortgage-backed securities 5 902 15 857 30 1,759 45 Collateralized mortgage obligations 7 4,941 155 15,314 777 20,255 932 Corporate debt securities 5 11,236 222 2,616 279 13,852 501 Total 245 $ 79,794 $ 1,882 $ 43,978 $ 2,963 $ 123,772 $ 4,845 As of December 31, 2017 Number of Securities Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands, except number of securities) State and political subdivisions 167 $ 33,237 $ 393 $ 25,843 $ 1,238 $ 59,080 $ 1,631 Mortgage-backed securities 4 349 2 887 11 1,236 13 Collateralized mortgage obligations 7 5,221 90 16,168 617 21,389 707 Corporate debt securities 3 3,093 4 2,617 277 5,710 281 Total 181 $ 41,900 $ 489 $ 45,515 $ 2,143 $ 87,415 $ 2,632 The Company's assessment of other-than-temporary impairment ("OTTI") is based on its reasonable judgment of the specific facts and circumstances impacting each individual debt security at the time such assessments are made. The Company reviews and considers factual information, including expected cash flows, the structure of the debt security, the creditworthiness of the issuer, the type of underlying assets and the current and anticipated market conditions. At March 31, 2018 and December 31, 2017 , 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. At March 31, 2018 , approximately 56% of the municipal bonds held by the Company were Iowa-based, and approximately 22% 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 believed that the municipal obligations identified in the tables above were temporarily impaired as of March 31, 2018 and December 31, 2017 . At March 31, 2018 and December 31, 2017 , 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 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 in the corporate bond portfolio. 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. During the first quarter of 2017 as part of the Company’s annual review and analysis of municipal investments, $1.2 million of municipal bonds from a single issuer in the held to maturity portfolio, which did not carry a credit rating from one of the major statistical rating agencies, were identified as having an elevated level of credit risk. While the instruments were currently making payments as agreed, certain financial trends were identified that provided material doubt as to the ability of the entity to continue to service the debt in the future. The investment securities were classified as “watch,” and the Company’s asset and liability management committee was notified of the situation. In early March 2017 the Company learned of a potential buyer for the investments and a bid to purchase was received and accepted. Investment securities designated as held to maturity may generally not be sold without calling into question the Company’s stated intention to hold other debt securities to maturity in the future (“tainting”), unless certain conditions are met that provide for an exception to accounting policy. One of these exceptions, as outlined under Accounting Standards Codification (“ASC”) 320-10-25-6(a), allows for the sale of an investment that is classified as held to maturity due to significant deterioration of the issuer’s creditworthiness. Since the bonds had been internally classified as “watch” due to credit deterioration, the Company believes that the sale was in accordance with the allowable provisions of ASC 320-10-25-6(a), and as such, does not “taint” the remainder of the held to maturity portfolio. A small gain was realized on the sale. The contractual maturity distribution of investment debt securities at March 31, 2018 , 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 $ 28,726 $ 28,807 $ — $ — Due after one year through five years 116,063 115,334 18,777 18,573 Due after five years through ten years 70,509 71,045 91,309 90,725 Due after ten years 13,051 12,836 61,445 59,184 Debt securities without a single maturity date 226,133 218,065 23,086 22,111 Total $ 454,482 $ 446,087 $ 194,617 $ 190,593 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. Proceeds from the sales of investment debt securities available for sale during the three months ended March 31, 2018 and March 31, 2017 were $0.5 million and zero , respectively. 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 three months ended March 31, 2018 and 2017 , were as follows: Three Months Ended March 31, 2018 2017 (in thousands) Available for sale debt securities: Gross realized gains $ 9 $ — Gross realized losses — — Other-than-temporary impairment — — 9 — Held to maturity debt securities: Gross realized gains — 43 The following tables present the net gains and losses on equity investments during the three months ended March 31, 2018 , disaggregated into realized and unrealized gains and losses: Three Months Ended March 31, 2018 (in thousands) Net losses recognized $ (24 ) Less: Net gains and losses recognized due to sales — Unrealized losses on securities still held at the reporting date $ (24 )

Loans Receivable and the Allowa

Loans Receivable and the Allowance for Loan Losses	3 Months Ended
	Mar. 31, 2018
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 March 31, 2018 and December 31, 2017 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Total March 31, 2018 Allowance for loan losses: Individually evaluated for impairment $ 580 $ 1,708 $ 3,338 $ 167 $ — $ 5,793 Collectively evaluated for impairment 2,573 6,654 11,408 2,254 282 23,171 Purchased credit impaired loans — — 251 456 — 707 Total $ 3,153 $ 8,362 $ 14,997 $ 2,877 $ 282 $ 29,671 Loans receivable Individually evaluated for impairment $ 10,945 $ 10,899 $ 17,448 $ 3,855 $ — $ 43,147 Collectively evaluated for impairment 101,030 502,824 1,166,913 457,180 36,030 2,263,977 Purchased credit impaired loans — 55 14,085 4,894 — 19,034 Total $ 111,975 $ 513,778 $ 1,198,446 $ 465,929 $ 36,030 $ 2,326,158 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Total December 31, 2017 Allowance for loan losses: Individually evaluated for impairment $ 140 $ 1,126 $ 2,157 $ 226 $ — $ 3,649 Collectively evaluated for impairment 2,650 7,392 11,144 2,182 244 23,612 Purchased credit impaired loans — — 336 462 — 798 Total $ 2,790 $ 8,518 $ 13,637 $ 2,870 $ 244 $ 28,059 Loans receivable Individually evaluated for impairment $ 2,969 $ 9,734 $ 10,386 $ 3,722 $ — $ 26,811 Collectively evaluated for impairment 102,543 493,844 1,147,133 460,475 36,158 2,240,153 Purchased credit impaired loans — 46 14,452 5,233 — 19,731 Total $ 105,512 $ 503,624 $ 1,171,971 $ 469,430 $ 36,158 $ 2,286,695 As of March 31, 2018 , the gross purchased credit impaired loans included above were $20.5 million , with a discount of $1.5 million . Loans with unpaid principal in the amount of $487.7 million and $477.6 million at March 31, 2018 and December 31, 2017 , respectively, were pledged to the Federal Home Loan Bank (the “FHLB”) as collateral for borrowings. The changes in the allowance for loan losses by portfolio segment were as follows: Allowance for Loan Loss Activity For the Three Months Ended March 31, 2018 and 2017 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Total 2018 Beginning balance $ 2,790 $ 8,518 $ 13,637 $ 2,870 $ 244 $ 28,059 Charge-offs — (87 ) (264 ) (104 ) (21 ) (476 ) Recoveries 6 79 76 62 15 238 Provision 357 (148 ) 1,548 49 44 1,850 Ending balance $ 3,153 $ 8,362 $ 14,997 $ 2,877 $ 282 $ 29,671 2017 Beginning balance $ 2,003 $ 6,274 $ 9,860 $ 3,458 $ 255 $ 21,850 Charge-offs (537 ) (65 ) (61 ) (28 ) (25 ) (716 ) Recoveries 10 19 10 — 3 42 Provision 984 (207 ) (58 ) 334 (12 ) 1,041 Ending balance $ 2,460 $ 6,021 $ 9,751 $ 3,764 $ 221 $ 22,217 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. Allowance for Loan and Lease Losses The Company requires the maintenance of an adequate allowance for loan and lease losses (“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.” 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 loan occurring during the stated periods: Three Months Ended March 31, 2018 2017 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 (1) : Commercial and industrial Extended maturity date — $ — $ — 6 $ 2,037 $ 2,083 Commercial real estate: Commercial real estate-other Extended maturity date — — — 1 968 968 Total — $ — $ — 7 $ 3,005 $ 3,051 (1) TDRs may include multiple concessions, and the disclosure classifications are based on the primary concession provided to the borrower. Loans by class modified as TDRs within 12 months of modification and for which there was a payment default during the stated periods were as follows: Three Months Ended March 31, 2018 2017 Number of Contracts Recorded Investment Number of Contracts Recorded Investment (dollars in thousands) Troubled Debt Restructurings (1) That Subsequently Defaulted: Commercial and industrial Extended maturity date — $ — 3 $ 954 Commercial real estate: Commercial real estate-other Extended maturity date 1 2,657 — — Total 1 $ 2,657 3 $ 954 (1) TDRs may include multiple concessions, and the disclosure classifications are based on the primary concession provided to the borrower. 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 or more are classified special mention/watch and substandard, respectively, for allocation purposes. The Company’s historical loss experience for each group segmented by loan type is calculated for the prior 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 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. 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 is performed to support these factor multiples. The following tables set forth the risk category of loans by class of loans and credit quality indicator based on the most recent analysis performed, as of March 31, 2018 and December 31, 2017 : Pass Special Mention/ Watch Substandard Doubtful Loss Total (in thousands) March 31, 2018 Agricultural $ 80,471 $ 19,883 $ 11,621 $ — $ — $ 111,975 Commercial and industrial 465,235 30,574 17,963 6 — 513,778 Commercial real estate: Construction and development 192,384 1,054 1,274 — — 194,712 Farmland 71,590 8,216 7,224 — — 87,030 Multifamily 124,203 1,417 1,182 — — 126,802 Commercial real estate-other 737,765 33,505 18,632 — — 789,902 Total commercial real estate 1,125,942 44,192 28,312 — — 1,198,446 Residential real estate: One- to four- family first liens 338,419 2,495 8,828 — — 349,742 One- to four- family junior liens 114,074 641 1,472 — — 116,187 Total residential real estate 452,493 3,136 10,300 — — 465,929 Consumer 35,817 136 47 30 — 36,030 Total $ 2,159,958 $ 97,921 $ 68,243 $ 36 $ — $ 2,326,158 Pass Special Mention/ Watch Substandard Doubtful Loss Total (in thousands) December 31, 2017 Agricultural $ 80,377 $ 21,989 $ 3,146 $ — $ — $ 105,512 Commercial and industrial 453,363 23,153 27,102 6 — 503,624 Commercial real estate: Construction and development 162,968 1,061 1,247 — — 165,276 Farmland 76,740 10,357 771 — — 87,868 Multifamily 131,507 2,498 501 — — 134,506 Commercial real estate-other 731,231 34,056 19,034 — — 784,321 Total commercial real estate 1,102,446 47,972 21,553 — — 1,171,971 Residential real estate: One- to four- family first liens 340,446 2,776 9,004 — — 352,226 One- to four- family junior liens 114,763 952 1,489 — — 117,204 Total residential real estate 455,209 3,728 10,493 — — 469,430 Consumer 36,059 — 68 31 — 36,158 Total $ 2,127,454 $ 96,842 $ 62,362 $ 37 $ — $ 2,286,695 Included within the special mention/watch, substandard, and doubtful categories at March 31, 2018 and December 31, 2017 are purchased credit impaired loans totaling $12.0 million and $12.6 million , respectively. Below are descriptions of the risk classifications of our loan portfolio. 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 March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 Recorded Investment Unpaid Principal Balance Related Allowance Recorded Investment Unpaid Principal Balance Related Allowance (in thousands) With no related allowance recorded: Agricultural $ 8,764 $ 9,264 $ — $ 1,523 $ 2,023 $ — Commercial and industrial 3,781 4,147 — 7,588 7,963 — Commercial real estate: Construction and development 84 84 — 84 84 — Farmland 3,952 3,952 — 287 287 — Multifamily 826 826 — — — — Commercial real estate-other 6,806 7,312 — 5,746 6,251 — Total commercial real estate 11,668 12,174 — 6,117 6,622 — Residential real estate: One- to four- family first liens 2,591 2,634 — 2,449 2,482 — One- to four- family junior liens 292 293 — 26 26 — Total residential real estate 2,883 2,927 — 2,475 2,508 — Consumer — — — — — — Total $ 27,096 $ 28,512 $ — $ 17,703 $ 19,116 $ — With an allowance recorded: Agricultural $ 2,181 $ 2,181 $ 580 $ 1,446 $ 1,446 $ 140 Commercial and industrial 7,118 7,207 1,708 2,146 2,177 1,126 Commercial real estate: Construction and development — — — — — — Farmland 2,092 2,092 676 — — — Multifamily — — — — — — Commercial real estate-other 3,688 11,320 2,662 4,269 11,536 2,157 Total commercial real estate 5,780 13,412 3,338 4,269 11,536 2,157 Residential real estate: One- to four- family first liens 972 972 167 979 979 185 One- to four- family junior liens — — — 268 268 41 Total residential real estate 972 972 167 1,247 1,247 226 Consumer — — — — — — Total $ 16,051 $ 23,772 $ 5,793 $ 9,108 $ 16,406 $ 3,649 Total: Agricultural $ 10,945 $ 11,445 $ 580 $ 2,969 $ 3,469 $ 140 Commercial and industrial 10,899 11,354 1,708 9,734 10,140 1,126 Commercial real estate: Construction and development 84 84 — 84 84 — Farmland 6,044 6,044 676 287 287 — Multifamily 826 826 — — — — Commercial real estate-other 10,494 18,632 2,662 10,015 17,787 2,157 Total commercial real estate 17,448 25,586 3,338 10,386 18,158 2,157 Residential real estate: One- to four- family first liens 3,563 3,606 167 3,428 3,461 185 One- to four- family junior liens 292 293 — 294 294 41 Total residential real estate 3,855 3,899 167 3,722 3,755 226 Consumer — — — — — — Total $ 43,147 $ 52,284 $ 5,793 $ 26,811 $ 35,522 $ 3,649 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: Three Months Ended March 31, 2018 2017 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized (in thousands) With no related allowance recorded: Agricultural $ 5,015 $ 124 $ 2,230 $ 13 Commercial and industrial 3,189 46 12,431 72 Commercial real estate: Construction and development 84 — 1,064 — Farmland 1,976 39 2,535 26 Multifamily 413 10 — — Commercial real estate-other 5,930 67 3,248 — Total commercial real estate 8,403 116 6,847 26 Residential real estate: One- to four- family first liens 1,602 — 2,563 — One- to four- family junior liens 293 — 13 — Total residential real estate 1,895 — 2,576 — Consumer — — — — Total $ 18,502 $ 286 $ 24,084 $ 111 With an allowance recorded: Agricultural $ 1,946 $ 17 $ 2,087 $ — Commercial and industrial 7,088 — 4,812 20 Commercial real estate: Construction and development — — 434 — Farmland 1,046 27 — — Multifamily — — — — Commercial real estate-other 4,141 — 6,369 — Total commercial real estate 5,187 27 6,803 — Residential real estate: One- to four- family first liens 976 9 1,400 9 One- to four- family junior liens — — — — Total residential real estate 976 9 1,400 9 Consumer — — — — Total $ 15,197 $ 53 $ 15,102 $ 29 Total: Agricultural $ 6,961 $ 141 $ 4,317 $ 13 Commercial and industrial 10,277 46 17,243 92 Commercial real estate: Construction and development 84 — 1,498 — Farmland 3,022 66 2,535 26 Multifamily 413 10 — — Commercial real estate-other 10,071 67 9,617 — Total commercial real estate 13,590 143 13,650 26 Residential real estate: One- to four- family first liens 2,578 9 3,963 9 One- to four- family junior liens 293 — 13 — Total residential real estate 2,871 9 3,976 9 Consumer — — — — Total $ 33,699 $ 339 $ 39,186 $ 140 The following table presents the contractual aging of the recorded investment in past due loans by class of loans at March 31, 2018 and December 31, 2017 : 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) March 31, 2018 Agricultural $ 1,722 $ 175 $ 138 $ 2,035 $ 109,940 $ 111,975 Commercial and industrial 5,523 136 1,599 7,258 506,520 513,778 Commercial real estate: Construction and development 11 — 177 188 194,524 194,712 Farmland 363 — — 363 86,667 87,030 Multifamily — — — — 126,802 126,802 Commercial real estate-other 2,778 48 1,081 3,907 785,995 789,902 Total commercial real estate 3,152 48 1,258 4,458 1,193,988 1,198,446 Residential real estate: One- to four- family first liens 2,968 444 1,177 4,589 345,153 349,742 One- to four- family junior liens 244 30 356 630 115,557 116,187 Total residential real estate 3,212 474 1,533 5,219 460,710 465,929 Consumer 58 15 19 92 35,938 36,030 Total $ 13,667 $ 848 $ 4,547 $ 19,062 $ 2,307,096 $ 2,326,158 Included in the totals above are the following purchased credit impaired loans $ — $ 206 $ 340 $ 546 $ 18,488 $ 19,034 December 31, 2017 Agricultural $ 95 $ 118 $ 168 $ 381 $ 105,131 $ 105,512 Commercial and industrial 1,434 1,336 1,576 4,346 499,278 503,624 Commercial real estate: Construction and development 57 97 82 236 165,040 165,276 Farmland 217 — 373 590 87,278 87,868 Multifamily — 25 — 25 134,481 134,506 Commercial real estate-other 74 — 1,852 1,926 782,395 784,321 Total commercial real estate 348 122 2,307 2,777 1,169,194 1,171,971 Residential real estate: One- to four- family first liens 3,854 756 1,019 5,629 346,597 352,226 One- to four- family junior liens 325 770 271 1,366 115,838 117,204 Total residential real estate 4,179 1,526 1,290 6,995 462,435 469,430 Consumer 79 15 29 123 36,035 36,158 Total $ 6,135 $ 3,117 $ 5,370 $ 14,622 $ 2,272,073 $ 2,286,695 Included in the totals above are the following purchased credit impaired loans $ 164 $ 756 $ 553 $ 1,473 $ 18,258 $ 19,731 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 90 days or more (unless the loan is both well secured with marketable collateral and in the process of collection). 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. Once a TDR has gone 90 days or more past due or is placed on nonaccrual status, it is included in the 90 days or more past due or nonaccrual totals. The following table sets forth the composition of the Company’s recorded investment in loans on nonaccrual status and past due 90 days or more and still accruing by class of loans, excluding purchased credit impaired loans, as of March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 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 $ 390 $ — $ 168 $ — Commercial and industrial 7,125 — 7,124 — Commercial real estate: Construction and development 186 — 188 — Farmland 140 — 386 — Multifamily — — — — Commercial real estate-other 3,924 — 5,279 — Total commercial real estate 4,250 — 5,853 — Residential real estate: One- to four- family first liens 1,312 103 1,228 205 One- to four- family junior liens 434 13 346 2 Total residential real estate 1,746 116 1,574 207 Consumer 55 — 65 — Total $ 13,566 $ 116 $ 14,784 $ 207 Not included in the loans above as of March 31, 2018 and December 31, 2017 were purchased credit impaired loans with an outstanding balance of $0.5 million and $0.7 million , ne

Derivative and Hedging Activiti

Derivative and Hedging Activities (Notes)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities Disclosure [Text Block]	Derivatives and Hedging Activities FASB ASC 815, Derivatives and Hedging (“ASC 815”), provides the disclosure requirements for derivatives and hedging activities with the intent to provide users of financial statements with an enhanced understanding of: (a) how and why an entity uses derivative instruments, (b) how the entity accounts for derivative instruments and related hedged items, and (c) how derivative instruments and related hedged items affect an entity’s financial position, financial performance, and cash flows. Further, qualitative disclosures are required that explain the Company’s objectives and strategies for using derivatives, as well as quantitative disclosures about the fair value of and gains and losses on derivative instruments, and disclosures about credit-risk-related contingent features in derivative instruments. As required by ASC 815, the Company records all derivatives on the balance sheet at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to changes in the fair value of an asset, liability, or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair value of the hedged asset or liability that are attributable to the hedged risk in a fair value hedge or the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain of its risk, even though hedge accounting does not apply or the Company elects not to apply hedge accounting. The Company does not use derivatives for trading or speculative purposes. In accordance with the FASB’s fair value measurement guidance, the Company made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio. The Company is exposed to certain risk arising from both its business operations and economic conditions. The Company principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The Company manages economic risks, including interest rate, liquidity, and credit risk primarily by managing the amount, sources, and duration of its assets and liabilities and the use of derivative financial instruments. Specifically, the Company enters into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally related to the Company’s loans and borrowings. The Company is exposed to changes in the fair value of certain of its fixed-rate assets due to changes in benchmark interest rates. The Company uses interest rate swaps to manage its exposure to changes in fair value on these instruments attributable to changes in the designated benchmark interest rate, LIBOR. Interest rate swaps designated as fair value hedges involve the payment of fixed-rate amounts to a counterparty in exchange for the Company receiving variable-rate payments over the life of the agreements without the exchange of the underlying notional amount. For derivatives designated and that qualify as fair value hedges, the gain or loss on the derivative as well as the offsetting loss or gain on the hedged item attributable to the hedged risk are recognized in interest income. As of March 31, 2018 , the Company had the following outstanding interest rate derivatives that were used to hedge changes in fair value attributable to interest rate risk: Interest Rate Derivative Number of Instruments Notional (dollars in thousands) Interest Rate Swaps 1 4,354 As of March 31, 2018 , the following amounts were recorded on the balance sheet related to cumulative basis adjustment for fair value hedges: Line Item in the Balance Sheet in Which the Hedged Item is Included Carrying Amount of the Hedged Assets Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Asset (in thousands) Loans 4,516 161 The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheet as of March 31, 2018 and December 31, 2017 : Fair Values of Derivative Instruments As of March 31, 2018 As of December 31, 2017 (in thousands) Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments: Interest rate products Other Liabilities 161 N/A — The table below presents the effect of the Company’s derivative financial instruments on the Consolidated Statements of Operations for the three months ended March 31, 2018 and March 31, 2017 : Location and Amount of Gain or Loss Recognized in Income on Fair Value Hedging Relationships For the Three Months Ended March 31, 2018 2017 (in thousands) Interest Income (Expense) Other Gain (Loss) Interest Income (Expense) Other Gain (Loss) Total amounts of income and expense line items presented in the Consolidated Statements of Operation in which the effects of fair value hedges are recorded (1 ) — — — The effects of fair value hedging: Loss on fair value hedging relationships in subtopic 815-20: Interest contracts: Hedged items (162 ) — — — Derivative designated as hedging instruments 161 — — — The table below presents a gross presentation, the effects of offsetting, and a net presentation of the Company’s derivatives as of March 31, 2018 and December 31, 2017 . The net amounts of derivative assets or liabilities can be reconciled to the tabular disclosure of fair value. The tabular disclosure of fair value provides the location that derivative assets and liabilities are presented on the Balance Sheet. Offsetting of Derivative Assets Gross Amounts Not Offset in the Balance Sheet (in thousands) Gross Amounts of Recognized Assets (Liabilities) Gross Amounts Offset in the Balance Sheet Net Amounts of Assets (Liabilities) presented in the Balance Sheet Financial Instruments Cash Collateral Received (Paid) Net Assets (Liabilities) As of March 31, 2018 Derivatives (161 ) — (161 ) — (130 ) (31 ) As of December 31, 2017 Derivatives — — — — — — Credit-risk-related Contingent Features The Company has an unsecured federal funds line with its derivative counterparty.The Company has an agreement with its derivative counterparty that contain a provision where if the Company defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then the Company could also be declared in default on its derivative obligations. The Company also has an agreement with its derivative counterparty that contains a provision where the Company could be declared in default on its derivative obligations if repayment of the underlying indebtedness is accelerated by the lender due to the Company's default on the indebtedness. As of March 31, 2018 , the fair value of derivatives in a net liability position, which includes accrued interest but excludes any adjustment for nonperformance risk, related to these agreements was $0.2 million . If the Company had breached any of these provisions at March 31, 2018 , it could have been required to settle its obligations under the agreements at their termination value of $0.2 million .

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2018
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 during the three months ended March 31, 2018 . The carrying amount of goodwill was $64.7 million at March 31, 2018 , the same as at December 31, 2017 . The following table presents the changes in the carrying amount of intangibles (excluding goodwill), gross carrying amount, accumulated amortization, and net book value as of and for the three months ended March 31, 2018 : Insurance Agency Intangible Core Deposit Intangible Indefinite-Lived Trade Name Intangible Finite-Lived Trade Name Intangible Customer List Intangible Total (in thousands) March 31, 2018 Balance, beginning of period $ 148 $ 4,011 $ 7,040 $ 744 $ 103 $ 12,046 Amortization expense (9 ) (594 ) — (50 ) (4 ) (657 ) Balance at end of period $ 139 $ 3,417 $ 7,040 $ 694 $ 99 $ 11,389 Gross carrying amount $ 1,320 $ 18,206 $ 7,040 $ 1,380 $ 330 $ 28,276 Accumulated amortizations (1,181 ) (14,789 ) — (686 ) (231 ) (16,887 ) Net book value $ 139 $ 3,417 $ 7,040 $ 694 $ 99 $ 11,389

Other Assets

Other Assets	3 Months Ended
	Mar. 31, 2018
Other Assets [Abstract]
Other Assets Disclosure [Text Block]	Other Assets The components of the Company’s other assets were as follows: March 31, 2018 December 31, 2017 (in thousands) Federal Home Loan Bank Stock $ 12,780 $ 11,324 Prepaid expenses 2,067 2,992 Mortgage servicing rights 2,536 2,316 Federal & state income taxes receivable, current 897 3,120 Accounts receivable & other miscellaneous assets 4,479 3,009 $ 22,759 $ 22,761 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. Redemption of this investment is at the option of the FHLB. No impairment was recorded on FHLB stock in the three months ended March 31, 2018 or in the year ended December 31, 2017 . 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 at the acquisition dates were estimated based on projected cash flows available for loss-share based on the credit adjustments estimated for each loan. The loss-share assets are recorded within other assets on the balance sheet. On July 14, 2017, the Bank, entered into an agreement with the FDIC that terminated all of the Bank's loss sharing agreements related to the former Central Bank. 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.

Short-Term Borrowings

Short-Term Borrowings	3 Months Ended
	Mar. 31, 2018
Short-term Debt [Abstract]
Short-term Debt [Text Block]	Short-Term Borrowings Short-term borrowings were as follows as of March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 (in thousands) Weighted Average Cost Balance Weighted Average Cost Balance Federal funds purchased 1.95 % $ 25,573 1.77 % $ 1,000 Securities sold under agreements to repurchase 0.72 67,738 0.71 96,229 Total 1.06 % $ 93,311 0.73 % $ 97,229 At March 31, 2018 and December 31, 2017 , the Company had no borrowings through the Federal Reserve Discount Window, while the borrowing capacity was $11.5 million as of March 31, 2018 and December 31, 2017 . As of March 31, 2018 and December 31, 2017 , the Bank had municipal securities pledged with a market value of $12.7 million and $12.8 million , respectively, to the Federal Reserve to secure potential borrowings. The Company also has various other unsecured federal funds agreements with correspondent banks. As of March 31, 2018 and December 31, 2017 , there were $25.6 million and $1.0 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 plus 2.00% . The line was renewed in May 2017, and matured on April 28, 2018 . It is expected to be renewed. The Company had no balance outstanding under this agreement as of March 31, 2018 .

Subordinated Notes Payable

Subordinated Notes Payable	3 Months Ended
	Mar. 31, 2018
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 March 31, 2018 and December 31, 2017 : Face Value Book Value Interest Rate Interest Rate at Maturity Date Callable Date (in thousands) 3/31/2018 March 31, 2018 Central Bancshares Capital Trust II (1) (2) $ 7,217 $ 6,688 Three-month LIBOR + 3.50% 5.62 % 03/15/2038 03/15/2013 Barron Investment Capital Trust I (1) (2) 2,062 1,665 Three-month LIBOR + 2.15% 4.42 % 09/23/2036 09/23/2011 MidWestOne Statutory Trust II (1) 15,464 15,464 Three-month LIBOR + 1.59% 3.71 % 12/15/2037 12/15/2012 Total $ 24,743 $ 23,817 Face Value Book Value Interest Rate Interest Rate at Maturity Date Callable Date (in thousands) 12/31/2017 December 31, 2017 Central Bancshares Capital Trust II (1) (2) $ 7,217 $ 6,674 Three-month LIBOR + 3.50% 5.09 % 03/15/2038 03/15/2013 Barron Investment Capital Trust I (1) (2) 2,062 1,655 Three-month LIBOR + 2.15% 3.82 % 09/23/2036 09/23/2011 MidWestOne Statutory Trust II (1) 15,464 15,464 Three-month LIBOR + 1.59% 3.18 % 12/15/2037 12/15/2012 Total $ 24,743 $ 23,793 (1) All distributions are cumulative and paid in cash quarterly. (2) Central Bancshares Capital Trust II and Barron Investment Capital Trust I were established by Central prior to the Company’s merger with Central, and the junior subordinated notes issued by Central 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 junior subordinated 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.

Long-Term Borrowings

Long-Term Borrowings	3 Months Ended
	Mar. 31, 2018
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 March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 (in thousands) Weighted Average Cost Balance Weighted Average Cost Balance FHLB Borrowings 1.93 % $ 123,000 1.72 % $ 115,000 Note payable to unaffiliated bank 3.41 11,250 3.32 12,500 Total 2.05 % $ 134,250 1.88 % $ 127,500 The Company utilizes FHLB borrowings as a supplement to customer deposits to fund interest-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. 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 , which began on September 30, 2015 . As of March 31, 2018 , $11.3 million of that note was outstanding.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Tax Disclosure [Text Block]	Income Taxes The income tax provisions for the three months ended March 31, 2018 and 2017 were less than the amounts computed by applying the maximum effective federal income tax rate of 21% and 35% , respectively, to the income before income taxes, because of the following items: For the Three Months Ended March 31, 2018 2017 (in thousands) Amount % of Pretax Income Amount % of Pretax Income Expected provision $ 2,053 21.0 % $ 3,235 35.0 % Tax-exempt interest (490 ) (5.0 ) (786 ) (8.5 ) Bank-owned life insurance (91 ) (0.9 ) (115 ) (1.2 ) State income taxes, net of federal income tax benefit 529 5.4 405 4.4 General business credits (47 ) (0.8 ) (21 ) (0.2 ) Other 30 0.6 (189 ) (2.1 ) Total income tax provision $ 1,984 20.3 % $ 2,529 27.4 % In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118 (SAB 118), which provides guidance regarding how a company is to reflect provisional amounts when necessary information is not yet available, prepared or analyzed sufficiently to complete its accounting for the effect of the changes in the Tax Cuts and Jobs Act (the “Tax Act”). During the first quarter of 2018, the income tax expense recorded during the fourth quarter of 2017 was determined to be final.

Earnings per Share

Earnings per Share	3 Months Ended
	Mar. 31, 2018
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. The following table presents the computation of earnings per common share for the respective periods: Three Months Ended March 31, (dollars in thousands, except per share amounts) 2018 2017 Basic earnings per common share computation Numerator: Net income $ 7,793 $ 6,713 Denominator: Weighted average shares outstanding 12,222,690 11,505,687 Basic earnings per common share $ 0.64 $ 0.58 Diluted earnings per common share computation Numerator: Net income $ 7,793 $ 6,713 Denominator: Weighted average shares outstanding, including all dilutive potential shares 12,241,714 11,555,356 Diluted earnings per common share $ 0.64 $ 0.58

Estimated Fair Value of Financi

Estimated Fair Value of Financial Instruments and Fair Value Measurements	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Disclosures [Text Block]	Estimated Fair Value of Financial Instruments and Fair Value Measurements Fair value is the exchange price that would be received for an asset or paid to transfer a liability (exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Market participants are defined as buyers and sellers in the principal (or most advantageous) market for the asset or liability that have all of the following characteristics: 1) an unrelated party; 2) knowledgeable (having a reasonable understanding about the asset or liability and the transaction based on all available information; including information that might be obtained through due diligence efforts that are usual or customary); 3) able to transact; and 4) willing to transact (motivated but not forced or otherwise compelled to do so). The FASB states “valuation techniques that are appropriate in the circumstances and for which sufficient data are available shall be used to measure fair value.” The valuation techniques for measuring fair value are consistent with the three traditional approaches to value: the market approach, the income approach, and the cost or asset approach. In applying valuation techniques, the use of relevant inputs (both observable and unobservable) based on the facts and circumstances must be used. The FASB has defined a fair value hierarchy for these inputs which prioritizes the inputs into three broad levels: • Level 1 Inputs – Quoted prices (unadjusted) for identical assets or liabilities in active markets. • Level 2 Inputs – Inputs other than quoted prices within Level 1 that are observable for assets or liabilities, either directly or indirectly. • Level 3 Inputs – Unobservable inputs for the asset or liability. Unobservable inputs should be used only to the extent that relevant observable inputs are not available; this allows for situations where there is little, if any, market activity for the asset or liability at the measurement date. Unobservable inputs should reflect the reporting entity’s own assumptions about the assumptions that market participants would use in pricing the asset or liability, including assumptions about risk. 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. The Company used the following methods and significant assumptions to estimate fair value: Investment Securities - The fair value for investment securities are determined by quoted market prices, if available (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, mortgage-backed securities, and collateralized mortgage 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 (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 (Level 2). On an annual basis, a group of selected municipal securities have their credit rating evaluated by a securities dealer and that information is used to verify the primary independent service’s rating and pricing. Loans Held for Sale - Loans held for sale are carried at the lower of cost or fair value, with fair value being based on binding contracts from third party investors (Level 2). The portfolio has historically consisted primarily of residential real estate loans. Loans, Net - The estimated fair value of loans, net, was performed using the income approach, with the market approach used for certain nonperforming loans, resulting in a Level 3 fair value classification. The application of the income approach establishes value by methods that discount or capitalize earnings and/or cash flow, by a discount or capitalization rate that reflects market rate of return expectations, market conditions, and the relative risk of the investment. Generally, this can be accomplished by the discounted cash flow method. For loans that exhibited some characteristics of performance and where it appears that the borrower may have adequate cash flows to service the loan, a discounted cash flow analysis was used. The discounted cash flow analysis was based on the contractual maturity of the loan and market indications of rates, prepayment speeds, defaults and credit risk. For loans with balloon or interest only payment structures, the repayment was extended by assuming a renewal period beyond the current contractual maturity date. For loans analyzed using the asset approach, the fair value was determined based on the estimated values of the underlying collateral. For impaired loans, the estimated net sales proceeds was used to determine the fair value of the loans when deemed appropriate. The implied sales proceeds value provides a better indication of value than the income stream as these loans are not performing or exhibit strong signs indicative of nonperformance. 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, based on appraisals. These appraisals may utilize a single valuation approach or a combination of approaches including comparable sales and the income approach. Adjustments are routinely made in the appraisal process by the independent appraisers to adjust for differences between the comparable sales and income data available for similar loans and collateral underlying such loans, and resulted in a Level 3 classification for inputs for determining fair value. Non-real estate collateral may be valued using an appraisal, net book value per the borrower’s financial statements, or aging reports, adjusted or discounted based on management’s historical knowledge, changes in market conditions from the time of valuation, and management’s expertise and knowledge of the client and the client’s business, resulting in a Level 3 fair value classification. Impaired loans are evaluated on a quarterly basis for additional impairment and adjusted in accordance with the allowance policy. 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. These assets are subsequently accounted for at the lower of cost or fair value less estimated costs to sell. Fair value is commonly based on recent real estate appraisals which are updated no less frequently than annually. These appraisals may utilize a single valuation approach or a combination of approaches, including comparable sales and the income approach. Adjustments are routinely made in the appraisal process by the independent appraisers to adjust for differences between the comparable sales and income data available for similar loans and the collateral underlying such loans, resulting in a Level 3 classification for inputs for determining fair value. Real estate owned properties are evaluated on a quarterly basis for additional impairment and adjusted accordingly. Appraisals for both collateral dependent impaired loans and OREO are performed by certified general appraisers (for commercial properties) or certified residential appraisers (for residential properties) whose qualifications and licenses have been reviewed and verified by the Company. Once received, a member of the Special Assets Department reviews the assumptions and approaches utilized in the appraisal as well as the overall resulting fair value in comparison with independent data sources such as recent market data or industry-wide statistics. Interest Rate Swaps and Loans - Interest rate swaps are valued by the Company's Swap Dealers using cash flow valuation techniques with observable market data inputs. The fair value of loans accounted for under the fair value option represents the net carrying value of the loan, plus the equal and opposite amount of the value of the swap needed to hedge the interest rate risk and an adjustment for credit risk based on our assessment of existing market conditions for the specific portfolio of loans. This is used due to the strict prepayment penalties put in the loan terms to cover the cost of exiting the hedge of the loans in the case of early prepayment or termination. The adjustment for credit risk on loans accounted for under the fair value option is not significant to the overall fair value of the loans. The fair values estimated by the Company's Swap Dealers use interest rates that are observable or that can be corroborated by observable market data and, therefore, are classified within Level 2 of the valuation hierarchy. The Company has entered into Collateral Agreements with its Swap Dealers which entitle it to receive collateral to cover market values on derivatives which are in asset position, thus a credit risk adjustment on interest rate swaps is not warranted. The Company regularly enters into interest rate lock commitments on mortgage loans to be held for sale with corresponding forward sales contracts related to these interest rate lock commitments, the fair values of which are calculated by applying observable market values from Fannie Mae TBA pricing to each interest rate lock commitment and forward sales contract, therefore, are classified within Level 2 of the valuation hierarchy. The following table summarizes assets and liabilities measured at fair value on a recurring basis as of March 31, 2018 and December 31, 2017 . The assets and liabilities are segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value: Fair Value Measurement at March 31, 2018 Using (in thousands) Fair Value 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. Government agencies and corporations $ 15,399 $ — $ 15,399 $ — State and political subdivisions 147,526 — 147,526 — Mortgage-backed securities 47,260 — 47,260 — Collateralized mortgage obligations 170,805 — 170,805 — Corporate debt securities 65,097 — 65,097 — Total available for sale debt securities $ 446,087 $ — $ 446,087 $ — Liabilities: Derivatives $ 161 $ — $ 161 $ — Fair Value Measurement at December 31, 2017 Using (in thousands) Fair Value 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. Government agencies and corporations $ 15,626 $ — $ 15,626 $ — State and political subdivisions 141,839 — 141,839 — Mortgage-backed securities 48,497 — 48,497 — Collateralized mortgage obligations 168,196 — 168,196 — Corporate debt securities 71,166 — 71,166 — Total available for sale debt securities $ 445,324 $ — $ 445,324 $ — Other equity securities 2,336 2,336 — — Total securities available for sale $ 447,660 $ 2,336 $ 445,324 $ — There were no transfers of assets between Level 3 of the fair value hierarchy during the three months ended March 31, 2018 or the year ended December 31, 2017 . Changes in the fair value of available for sale debt securities are included in other comprehensive income, and changes in the fair value of equity securities are included in noninterest income. 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 March 31, 2018 and December 31, 2017 , as more fully described above. Fair Value Measurement at March 31, 2018 Using (in thousands) Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Collateral dependent impaired loans $ 8,877 $ — $ — $ 8,877 Other real estate owned $ 1,001 $ — $ — $ 1,001 Fair Value Measurement at December 31, 2017 Using (in thousands) Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Collateral dependent impaired loans $ 3,927 $ — $ — $ 3,927 Other real estate owned $ 2,010 $ — $ — $ 2,010 The following presents the valuation technique(s), unobservable inputs, and quantitative information about the unobservable inputs used for fair value measurements of the financial instruments held by the Company at March 31, 2018 , categorized within Level 3 of the fair value hierarchy: Quantitative Information About Level 3 Fair Value Measurements (dollars in thousands) Fair Value at March 31, 2018 Valuation Techniques(s) Unobservable Input Range of Inputs Weighted Average Collateral dependent impaired loans $ 8,877 Modified appraised value Third party appraisal NM * - NM * NM * Appraisal discount NM * - NM * NM * Other real estate owned $ 1,001 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. Due to the adoption of ASU 2016-01 as of January 1, 2018, the estimated fair value amounts shown for December 31, 2017 are not comparable to those for March 31, 2018 , due to a change in the required methodology (“exit price” only) for determining current estimated fair value. The carrying amount and estimated fair value of financial instruments not carried at fair value, at March 31, 2018 and December 31, 2017 are as follows: March 31, 2018 Carrying Amount Estimated Fair Value Quoted Significant Other Significant (in thousands) Financial assets: Cash and cash equivalents $ 42,396 $ 42,396 $ 42,396 $ — $ — Investment securities: Equity securities 2,815 2,815 2,815 — — Available for sale debt securities 446,087 446,087 — 446,087 — Held to maturity debt securities 194,617 190,593 — 190,593 — Total investment securities 643,519 639,495 2,815 636,680 — Loans held for sale 870 895 — 895 — Loans, net 2,296,487 2,247,398 — — 2,247,398 Accrued interest receivable 13,337 13,337 13,337 — — Federal Home Loan Bank stock 12,780 12,780 — 12,780 — Financial liabilities: Deposits: Non-interest bearing demand 450,168 450,168 450,168 — — Interest-bearing checking 1,240,208 1,240,208 1,240,208 — — Savings 215,940 215,940 215,940 — — Certificates of deposit under $100,000 332,727 328,009 — 328,009 — Certificates of deposit $100,000 and over 392,878 389,430 — 389,430 — Total deposits 2,631,921 2,623,755 1,906,316 717,439 — Federal funds purchased and securities sold under agreements to repurchase 93,311 93,311 93,311 — — Federal Home Loan Bank borrowings 123,000 120,850 — 120,850 — Junior subordinated notes issued to capital trusts 23,817 21,032 — 21,032 — Long-term debt 11,250 11,250 — 11,250 — Derivative liability 161 161 — 161 — December 31, 2017 Carrying Amount Estimated Fair Value Quoted Prices in Markets for Significant Other Significant (in thousands) Financial assets: Cash and cash equivalents $ 50,972 $ 50,972 $ 50,972 $ — $ — Investment securities: Equity securities 2,336 2,336 2,336 — — Available for sale debt securities 445,324 445,324 — 445,324 — Held to maturity debt securities 195,619 194,343 — 194,343 — Total investment securities 643,279 642,003 2,336 639,667 — Loans held for sale 856 871 — — 871 Loans, net 2,258,636 2,256,726 — 2,256,726 — Accrued interest receivable 14,732 14,732 14,732 — — Federal Home Loan Bank stock 11,324 11,324 — 11,324 — Financial liabilities: Deposits: Non-interest bearing demand 461,969 461,969 461,969 — — Interest-bearing checking 1,228,112 1,228,112 1,228,112 — — Savings 213,430 213,430 213,430 — — Certificates of deposit under $100,000 324,681 321,197 — 321,197 — Certificates of deposit $100,000 and over 377,127 374,685 — 374,685 — Total deposits 2,605,319 2,599,393 1,903,511 695,882 — Federal funds purchased and securities sold under agreements to repurchase 97,229 97,229 97,229 — — Federal Home Loan Bank borrowings 115,000 114,945 — 114,945 — Junior subordinated notes issued to capital trusts 23,793 19,702 — 19,702 — Long-term debt 12,500 12,500 — 12,500 —

Revenue Recognition (Notes)

Revenue Recognition (Notes)	3 Months Ended
	Mar. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	Revenue Recognition On January 1, 2018, the Company adopted ASU No. 2014-09 “Revenue from Contracts with Customers” (Topic 606) and all subsequent ASUs that modified Topic 606. As stated in Note 2. “Effect of New Financial Accounting Standards,” the implementation of the new standard did not have a material impact on the measurement or recognition of revenue; as such, a cumulative effect adjustment to opening retained earnings was not deemed necessary. Results for reporting periods beginning after January 1, 2018 are presented under Topic 606, while prior period amounts were not adjusted and continue to be reported in accordance with our historic accounting under Topic 605. Topic 606 does not apply to revenue associated with financial instruments, including revenue from loans and securities. In addition, certain noninterest income streams such as fees associated with mortgage servicing rights, financial guarantees, derivatives, and certain credit card fees are also not in scope of the new guidance. Topic 606 is applicable to noninterest revenue streams such as trust and asset management fees, service charges on deposit accounts, sales of other real estate, and debit card interchange fees. However, the recognition of these revenue streams did not change significantly upon adoption of Topic 606. Substantially all of the Company’s revenue is generated from contracts with customers. Noninterest revenue streams in-scope of Topic 606 are discussed below. Trust and Asset Management Trust and asset management income is primarily comprised of fees earned from the management and administration of trusts and other customer assets. The Company’s performance obligation is generally satisfied over time and the resulting fees are recognized monthly, based upon the month-end market value of the assets under management and the applicable fee rate. Payment is generally received a few days after month end through a direct charge to customers’ accounts. The Company does not earn performance-based incentives. Optional services such as real estate sales and tax return preparation services are also available to existing trust and asset management customers. The Company’s performance obligation for these transactional-based services is generally satisfied, and related revenue recognized, at a point in time (i.e., as incurred). Payment is received shortly after services are rendered. Service Charges on Deposit Accounts Service charges on deposit accounts consist of account analysis fees (i.e., net fees earned on analyzed business and public checking accounts), monthly service fees, check orders, and other deposit account related fees. The Company’s performance obligation for account analysis fees and monthly service fees is generally satisfied, and the related revenue recognized, over the period in which the service is provided. Check orders and other deposit account related fees are largely transactional based, and therefore, the Company’s performance obligation is satisfied, and related revenue recognized, at a point in time. Payment for service charges on deposit accounts is primarily received immediately or in the following month through a direct charge to customers’ accounts. Fees, Exchange, and Other Service Charges Fees, exchange, and other service charges are primarily comprised of debit and credit card income, ATM fees, merchant services income, and other service charges. Debit and credit card income is primarily comprised of interchange fees earned whenever the Company’s debit and credit cards are processed through card payment networks such as Visa. ATM fees are primarily generated when a Company cardholder uses a non-Company ATM or a non-Company cardholder uses a Company ATM. Merchant services income mainly represents fees charged to merchants to process their debit and credit card transactions, in addition to account management fees. Other service charges include revenue from processing wire transfers, bill pay service, cashier’s checks, and other services. The Company’s performance obligation for fees, exchange, and other service charges are largely satisfied, and related revenue recognized, when the services are rendered or upon completion. Payment is typically received immediately or in the following month. Gains/Losses on Sales of OREO Gain or loss from the sale of OREO occurs when control of the property transfers to the buyer, which generally occurs at the time of an executed deed. When the Company finances the sale of OREO to the buyer, the Company assesses whether the buyer is committed to perform their obligations under the contract and whether collectability of the transaction price is probable. Once these criteria are met, the OREO asset is derecognized and the gain or loss on sale is recorded upon the transfer of control of the property to the buyer. In determining the gain or loss on the sale, the Company adjusts the transaction price and related gain (loss) on sale if a significant financing component is present. OREO sales for the three months ended March 31, 2018 and March 31, 2017 were not financed by the Bank. Other Other noninterest income consists of other recurring revenue streams such as safe deposit box rental fees, and other miscellaneous revenue streams. Safe deposit box rental fees are charged to the customer on an annual basis and recognized upon receipt of payment. The Company determined that since rentals and renewals occur fairly consistently over time, revenue is recognized on a basis consistent with the duration of the performance obligation. Contract Balances A contract asset balance occurs when an entity performs a service for a customer before the customer pays consideration (resulting in a contract receivable) or before payment is due (resulting in a contract asset). A contract liability balance is an entity’s obligation to transfer a service to a customer for which the entity has already received payment (or payment is due) from the customer. The Company’s noninterest revenue streams are largely based on transactional activity, or standard month-end revenue accruals such as asset management fees based on month-end market values. Consideration is often received immediately or shortly after the Company satisfies its performance obligation and revenue is recognized. The Company does not typically enter into long-term revenue contracts with customers, and therefore, does not experience significant contract balances. As of March 31, 2018 and December 31, 2017 , the Company did not have any significant contract balances. Contract Acquisition Costs In connection with the adoption of Topic 606, an entity is required to capitalize, and subsequently amortize into expense, certain incremental costs of obtaining a contract with a customer if these costs are expected to be recovered. The incremental costs of obtaining a contract are those costs that an entity incurs to obtain a contract with a customer that it would not have incurred if the contract had not been obtained (for example, sales commission). The Company utilizes the practical expedient which allows entities to immediately expense contract acquisition costs when the asset that would have resulted from capitalizing these costs would have been amortized in one year or less. Upon adoption of Topic 606, the Company did not capitalize any contract acquisition cost.

Operating Segments

Operating Segments	3 Months Ended
	Mar. 31, 2018
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, Florida, and Denver, Colorado. Substantially all income is derived from a diverse base of commercial, mortgage and retail lending activities, and investments.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2018
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 March 31, 2018 , but prior to the date the consolidated financial statements were issued, that provided additional evidence about conditions that existed at March 31, 2018 have been recognized in the consolidated financial statements for the three months ended March 31, 2018 . Events or transactions that provided evidence about conditions that did not exist at March 31, 2018 , but arose before the consolidated financial statements were issued, have not been recognized in the consolidated financial statements for the three months ended March 31, 2018 . On April 19, 2018 , the board of directors of the Company declared a cash dividend of $0.195 per share payable on June 15, 2018 to shareholders of record as of the close of business on June 1, 2018 .

Significant Accounting Policies

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Certain Loans and Debt Securities Acquired in Transfer, Recognizing Interest Income on Impaired Loans, Policy [Policy Text Block]	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.
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, Allowance for Loan Losses Policy [Policy Text Block]	Allowance for Loan and Lease Losses The Company requires the maintenance of an adequate allowance for loan and lease losses (“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.”
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 90 days or more (unless the loan is both well secured with marketable collateral and in the process of collection). 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. Once a TDR has gone 90 days or more past due or is placed on nonaccrual status, it is included in the 90 days or more past due or nonaccrual totals.
Derivatives, Policy [Policy Text Block]	FASB ASC 815, Derivatives and Hedging (“ASC 815”), provides the disclosure requirements for derivatives and hedging activities with the intent to provide users of financial statements with an enhanced understanding of: (a) how and why an entity uses derivative instruments, (b) how the entity accounts for derivative instruments and related hedged items, and (c) how derivative instruments and related hedged items affect an entity’s financial position, financial performance, and cash flows. Further, qualitative disclosures are required that explain the Company’s objectives and strategies for using derivatives, as well as quantitative disclosures about the fair value of and gains and losses on derivative instruments, and disclosures about credit-risk-related contingent features in derivative instruments. As required by ASC 815, the Company records all derivatives on the balance sheet at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to changes in the fair value of an asset, liability, or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair value of the hedged asset or liability that are attributable to the hedged risk in a fair value hedge or the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain of its risk, even though hedge accounting does not apply or the Company elects not to apply hedge accounting. The Company does not use derivatives for trading or speculative purposes. In accordance with the FASB’s fair value measurement guidance, the Company made an accounting policy election to measure the credit risk of its derivative financial instruments that are subject to master netting agreements on a net basis by counterparty portfolio.
Fair Value of Financial Instruments, Policy [Policy Text Block]	Fair value is the exchange price that would be received for an asset or paid to transfer a liability (exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Market participants are defined as buyers and sellers in the principal (or most advantageous) market for the asset or liability that have all of the following characteristics: 1) an unrelated party; 2) knowledgeable (having a reasonable understanding about the asset or liability and the transaction based on all available information; including information that might be obtained through due diligence efforts that are usual or customary); 3) able to transact; and 4) willing to transact (motivated but not forced or otherwise compelled to do so). The FASB states “valuation techniques that are appropriate in the circumstances and for which sufficient data are available shall be used to measure fair value.” The valuation techniques for measuring fair value are consistent with the three traditional approaches to value: the market approach, the income approach, and the cost or asset approach. In applying valuation techniques, the use of relevant inputs (both observable and unobservable) based on the facts and circumstances must be used. The FASB has defined a fair value hierarchy for these inputs which prioritizes the inputs into three broad levels: • Level 1 Inputs – Quoted prices (unadjusted) for identical assets or liabilities in active markets. • Level 2 Inputs – Inputs other than quoted prices within Level 1 that are observable for assets or liabilities, either directly or indirectly. • Level 3 Inputs – Unobservable inputs for the asset or liability. Unobservable inputs should be used only to the extent that relevant observable inputs are not available; this allows for situations where there is little, if any, market activity for the asset or liability at the measurement date. Unobservable inputs should reflect the reporting entity’s own assumptions about the assumptions that market participants would use in pricing the asset or liability, including assumptions about risk. 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.
Fair Value Measurement, Policy [Policy Text Block]	The Company used the following methods and significant assumptions to estimate fair value: Investment Securities - The fair value for investment securities are determined by quoted market prices, if available (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, mortgage-backed securities, and collateralized mortgage 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 (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 (Level 2). On an annual basis, a group of selected municipal securities have their credit rating evaluated by a securities dealer and that information is used to verify the primary independent service’s rating and pricing. Loans Held for Sale - Loans held for sale are carried at the lower of cost or fair value, with fair value being based on binding contracts from third party investors (Level 2). The portfolio has historically consisted primarily of residential real estate loans. Loans, Net - The estimated fair value of loans, net, was performed using the income approach, with the market approach used for certain nonperforming loans, resulting in a Level 3 fair value classification. The application of the income approach establishes value by methods that discount or capitalize earnings and/or cash flow, by a discount or capitalization rate that reflects market rate of return expectations, market conditions, and the relative risk of the investment. Generally, this can be accomplished by the discounted cash flow method. For loans that exhibited some characteristics of performance and where it appears that the borrower may have adequate cash flows to service the loan, a discounted cash flow analysis was used. The discounted cash flow analysis was based on the contractual maturity of the loan and market indications of rates, prepayment speeds, defaults and credit risk. For loans with balloon or interest only payment structures, the repayment was extended by assuming a renewal period beyond the current contractual maturity date. For loans analyzed using the asset approach, the fair value was determined based on the estimated values of the underlying collateral. For impaired loans, the estimated net sales proceeds was used to determine the fair value of the loans when deemed appropriate. The implied sales proceeds value provides a better indication of value than the income stream as these loans are not performing or exhibit strong signs indicative of nonperformance. 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, based on appraisals. These appraisals may utilize a single valuation approach or a combination of approaches including comparable sales and the income approach. Adjustments are routinely made in the appraisal process by the independent appraisers to adjust for differences between the comparable sales and income data available for similar loans and collateral underlying such loans, and resulted in a Level 3 classification for inputs for determining fair value. Non-real estate collateral may be valued using an appraisal, net book value per the borrower’s financial statements, or aging reports, adjusted or discounted based on management’s historical knowledge, changes in market conditions from the time of valuation, and management’s expertise and knowledge of the client and the client’s business, resulting in a Level 3 fair value classification. Impaired loans are evaluated on a quarterly basis for additional impairment and adjusted in accordance with the allowance policy. 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. These assets are subsequently accounted for at the lower of cost or fair value less estimated costs to sell. Fair value is commonly based on recent real estate appraisals which are updated no less frequently than annually. These appraisals may utilize a single valuation approach or a combination of approaches, including comparable sales and the income approach. Adjustments are routinely made in the appraisal process by the independent appraisers to adjust for differences between the comparable sales and income data available for similar loans and the collateral underlying such loans, resulting in a Level 3 classification for inputs for determining fair value. Real estate owned properties are evaluated on a quarterly basis for additional impairment and adjusted accordingly. Appraisals for both collateral dependent impaired loans and OREO are performed by certified general appraisers (for commercial properties) or certified residential appraisers (for residential properties) whose qualifications and licenses have been reviewed and verified by the Company. Once received, a member of the Special Assets Department reviews the assumptions and approaches utilized in the appraisal as well as the overall resulting fair value in comparison with independent data sources such as recent market data or industry-wide statistics. Interest Rate Swaps and Loans - Interest rate swaps are valued by the Company's Swap Dealers using cash flow valuation techniques with observable market data inputs. The fair value of loans accounted for under the fair value option represents the net carrying value of the loan, plus the equal and opposite amount of the value of the swap needed to hedge the interest rate risk and an adjustment for credit risk based on our assessment of existing market conditions for the specific portfolio of loans. This is used due to the strict prepayment penalties put in the loan terms to cover the cost of exiting the hedge of the loans in the case of early prepayment or termination. The adjustment for credit risk on loans accounted for under the fair value option is not significant to the overall fair value of the loans. The fair values estimated by the Company's Swap Dealers use interest rates that are observable or that can be corroborated by observable market data and, therefore, are classified within Level 2 of the valuation hierarchy. The Company has entered into Collateral Agreements with its Swap Dealers which entitle it to receive collateral to cover market values on derivatives which are in asset position, thus a credit risk adjustment on interest rate swaps is not warranted. The Company regularly enters into interest rate lock commitments on mortgage loans to be held for sale with corresponding forward sales contracts related to these interest rate lock commitments, the fair values of which are calculated by applying observable market values from Fannie Mae TBA pricing to each interest rate lock commitment and forward sales contract, therefore, are classified within Level 2 of the valuation hierarchy.

Investment Securities (Tables)

Investment Securities (Tables)	3 Months Ended
	Mar. 31, 2018
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: As of March 31, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) U.S. Government agencies and corporations $ 15,678 $ — $ 279 $ 15,399 State and political subdivisions 146,386 1,663 523 147,526 Mortgage-backed securities 48,065 147 952 47,260 Collateralized mortgage obligations 178,068 13 7,276 170,805 Corporate debt securities 66,285 25 1,213 65,097 Total $ 454,482 $ 1,848 $ 10,243 $ 446,087 As of December 31, 2017 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) U.S. Government agencies and corporations $ 15,716 $ — $ 90 $ 15,626 State and political subdivisions 139,561 2,475 197 141,839 Mortgage-backed securities 48,744 181 428 48,497 Collateralized mortgage obligations 173,339 29 5,172 168,196 Corporate debt securities 71,562 31 427 71,166 Total debt securities 448,922 2,716 6,314 445,324 Other equity securities 2,268 124 56 2,336 Total $ 451,190 $ 2,840 $ 6,370 $ 447,660
Held-to-maturity Securities [Table Text Block]	The amortized cost and fair value of investment debt securities held to maturity, with gross unrealized gains and losses, are as follows: As of March 31, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) U.S. Government agencies and corporations $ 10,047 $ — $ 278 $ 9,769 State and political subdivisions 126,356 315 3,089 123,582 Mortgage-backed securities 1,882 2 45 1,839 Collateralized mortgage obligations 21,204 — 932 20,272 Corporate debt securities 35,128 504 501 35,131 Total $ 194,617 $ 821 $ 4,845 $ 190,593 As of December 31, 2017 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) U.S. Government agencies and corporations $ 10,049 $ — $ — $ 10,049 State and political subdivisions 126,413 804 1,631 125,586 Mortgage-backed securities 1,906 4 13 1,897 Collateralized mortgage obligations 22,115 — 707 21,408 Corporate debt securities 35,136 548 281 35,403 Total $ 195,619 $ 1,356 $ 2,632 $ 194,343
Schedule of Temporary Impairment Losses, Investments [Table Text Block]	The following tables present information pertaining to securities with gross unrealized losses as of March 31, 2018 and December 31, 2017 , aggregated by investment category and length of time that individual securities have been in a continuous loss position: As of March 31, 2018 Number of Securities Less than 12 Months 12 Months or More Total Available for Sale Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands, except number of securities) U.S. Government agencies and corporations 3 $ 15,399 $ 279 $ — $ — $ 15,399 $ 279 State and political subdivisions 72 33,470 452 2,757 71 36,227 523 Mortgage-backed securities 21 36,330 871 3,627 81 39,957 952 Collateralized mortgage obligations 41 47,328 1,010 117,834 6,266 165,162 7,276 Corporate debt securities 12 54,639 995 8,576 218 63,215 1,213 Total 149 $ 187,166 $ 3,607 $ 132,794 $ 6,636 $ 319,960 $ 10,243 As of December 31, 2017 Number of Securities Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands, except number of securities) U.S. Government agencies and corporations 3 $ 15,626 $ 90 $ — $ — $ 15,626 $ 90 State and political subdivisions 34 11,705 167 1,800 30 13,505 197 Mortgage-backed securities 20 37,964 359 3,961 69 41,925 428 Collateralized mortgage obligations 35 37,881 489 122,757 4,683 160,638 5,172 Corporate debt securities 12 55,340 298 8,778 129 64,118 427 Other equity securities 1 — — 1,944 56 1,944 56 Total 105 $ 158,516 $ 1,403 $ 139,240 $ 4,967 $ 297,756 $ 6,370 As of March 31, 2018 Number of Securities Less than 12 Months 12 Months or More Total Held to Maturity Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands, except number of securities) U.S. Government agencies and corporations 1 $ 9,769 $ 278 $ — $ — $ 9,769 $ 278 State and political subdivisions 227 52,946 1,212 25,191 1,877 78,137 3,089 Mortgage-backed securities 5 902 15 857 30 1,759 45 Collateralized mortgage obligations 7 4,941 155 15,314 777 20,255 932 Corporate debt securities 5 11,236 222 2,616 279 13,852 501 Total 245 $ 79,794 $ 1,882 $ 43,978 $ 2,963 $ 123,772 $ 4,845 As of December 31, 2017 Number of Securities Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in thousands, except number of securities) State and political subdivisions 167 $ 33,237 $ 393 $ 25,843 $ 1,238 $ 59,080 $ 1,631 Mortgage-backed securities 4 349 2 887 11 1,236 13 Collateralized mortgage obligations 7 5,221 90 16,168 617 21,389 707 Corporate debt securities 3 3,093 4 2,617 277 5,710 281 Total 181 $ 41,900 $ 489 $ 45,515 $ 2,143 $ 87,415 $ 2,632
Investments Classified by Contractual Maturity Date [Table Text Block]	The contractual maturity distribution of investment debt securities at March 31, 2018 , 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 $ 28,726 $ 28,807 $ — $ — Due after one year through five years 116,063 115,334 18,777 18,573 Due after five years through ten years 70,509 71,045 91,309 90,725 Due after ten years 13,051 12,836 61,445 59,184 Debt securities without a single maturity date 226,133 218,065 23,086 22,111 Total $ 454,482 $ 446,087 $ 194,617 $ 190,593
Realized Gain (Loss) on Investments [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 three months ended March 31, 2018 and 2017 , were as follows: Three Months Ended March 31, 2018 2017 (in thousands) Available for sale debt securities: Gross realized gains $ 9 $ — Gross realized losses — — Other-than-temporary impairment — — 9 — Held to maturity debt securities: Gross realized gains — 43
Trading Securities [Table Text Block]	The following tables present the net gains and losses on equity investments during the three months ended March 31, 2018 , disaggregated into realized and unrealized gains and losses: Three Months Ended March 31, 2018 (in thousands) Net losses recognized $ (24 ) Less: Net gains and losses recognized due to sales — Unrealized losses on securities still held at the reporting date $ (24 )

Loans Receivable and the Allo27

Loans Receivable and the Allowance for Loan Losses (Tables)	3 Months Ended
	Mar. 31, 2018
Loans and Leases Receivable Disclosure [Abstract]
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]	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 March 31, 2018 and December 31, 2017 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Total March 31, 2018 Allowance for loan losses: Individually evaluated for impairment $ 580 $ 1,708 $ 3,338 $ 167 $ — $ 5,793 Collectively evaluated for impairment 2,573 6,654 11,408 2,254 282 23,171 Purchased credit impaired loans — — 251 456 — 707 Total $ 3,153 $ 8,362 $ 14,997 $ 2,877 $ 282 $ 29,671 Loans receivable Individually evaluated for impairment $ 10,945 $ 10,899 $ 17,448 $ 3,855 $ — $ 43,147 Collectively evaluated for impairment 101,030 502,824 1,166,913 457,180 36,030 2,263,977 Purchased credit impaired loans — 55 14,085 4,894 — 19,034 Total $ 111,975 $ 513,778 $ 1,198,446 $ 465,929 $ 36,030 $ 2,326,158 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Total December 31, 2017 Allowance for loan losses: Individually evaluated for impairment $ 140 $ 1,126 $ 2,157 $ 226 $ — $ 3,649 Collectively evaluated for impairment 2,650 7,392 11,144 2,182 244 23,612 Purchased credit impaired loans — — 336 462 — 798 Total $ 2,790 $ 8,518 $ 13,637 $ 2,870 $ 244 $ 28,059 Loans receivable Individually evaluated for impairment $ 2,969 $ 9,734 $ 10,386 $ 3,722 $ — $ 26,811 Collectively evaluated for impairment 102,543 493,844 1,147,133 460,475 36,158 2,240,153 Purchased credit impaired loans — 46 14,452 5,233 — 19,731 Total $ 105,512 $ 503,624 $ 1,171,971 $ 469,430 $ 36,158 $ 2,286,695
Allowance for Credit Losses on Financing Receivables [Table Text Block]	The changes in the allowance for loan losses by portfolio segment were as follows: Allowance for Loan Loss Activity For the Three Months Ended March 31, 2018 and 2017 (in thousands) Agricultural Commercial and Industrial Commercial Real Estate Residential Real Estate Consumer Total 2018 Beginning balance $ 2,790 $ 8,518 $ 13,637 $ 2,870 $ 244 $ 28,059 Charge-offs — (87 ) (264 ) (104 ) (21 ) (476 ) Recoveries 6 79 76 62 15 238 Provision 357 (148 ) 1,548 49 44 1,850 Ending balance $ 3,153 $ 8,362 $ 14,997 $ 2,877 $ 282 $ 29,671 2017 Beginning balance $ 2,003 $ 6,274 $ 9,860 $ 3,458 $ 255 $ 21,850 Charge-offs (537 ) (65 ) (61 ) (28 ) (25 ) (716 ) Recoveries 10 19 10 — 3 42 Provision 984 (207 ) (58 ) 334 (12 ) 1,041 Ending balance $ 2,460 $ 6,021 $ 9,751 $ 3,764 $ 221 $ 22,217
Troubled Debt Restructurings on Financing Receivables [Table Text Block]	The following table sets forth information on the Company’s TDRs by class of loan occurring during the stated periods: Three Months Ended March 31, 2018 2017 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 (1) : Commercial and industrial Extended maturity date — $ — $ — 6 $ 2,037 $ 2,083 Commercial real estate: Commercial real estate-other Extended maturity date — — — 1 968 968 Total — $ — $ — 7 $ 3,005 $ 3,051 (1) TDRs may include multiple concessions, and the disclosure classifications are based on the primary concession provided to the borrower. Loans by class modified as TDRs within 12 months of modification and for which there was a payment default during the stated periods were as follows: Three Months Ended March 31, 2018 2017 Number of Contracts Recorded Investment Number of Contracts Recorded Investment (dollars in thousands) Troubled Debt Restructurings (1) That Subsequently Defaulted: Commercial and industrial Extended maturity date — $ — 3 $ 954 Commercial real estate: Commercial real estate-other Extended maturity date 1 2,657 — — Total 1 $ 2,657 3 $ 954 (1) TDRs may include multiple concessions, and the disclosure classifications are based on the primary concession provided to the borrower.
Financing Receivable Credit Quality Indicators [Table Text Block]	The following tables set forth the risk category of loans by class of loans and credit quality indicator based on the most recent analysis performed, as of March 31, 2018 and December 31, 2017 : Pass Special Mention/ Watch Substandard Doubtful Loss Total (in thousands) March 31, 2018 Agricultural $ 80,471 $ 19,883 $ 11,621 $ — $ — $ 111,975 Commercial and industrial 465,235 30,574 17,963 6 — 513,778 Commercial real estate: Construction and development 192,384 1,054 1,274 — — 194,712 Farmland 71,590 8,216 7,224 — — 87,030 Multifamily 124,203 1,417 1,182 — — 126,802 Commercial real estate-other 737,765 33,505 18,632 — — 789,902 Total commercial real estate 1,125,942 44,192 28,312 — — 1,198,446 Residential real estate: One- to four- family first liens 338,419 2,495 8,828 — — 349,742 One- to four- family junior liens 114,074 641 1,472 — — 116,187 Total residential real estate 452,493 3,136 10,300 — — 465,929 Consumer 35,817 136 47 30 — 36,030 Total $ 2,159,958 $ 97,921 $ 68,243 $ 36 $ — $ 2,326,158 Pass Special Mention/ Watch Substandard Doubtful Loss Total (in thousands) December 31, 2017 Agricultural $ 80,377 $ 21,989 $ 3,146 $ — $ — $ 105,512 Commercial and industrial 453,363 23,153 27,102 6 — 503,624 Commercial real estate: Construction and development 162,968 1,061 1,247 — — 165,276 Farmland 76,740 10,357 771 — — 87,868 Multifamily 131,507 2,498 501 — — 134,506 Commercial real estate-other 731,231 34,056 19,034 — — 784,321 Total commercial real estate 1,102,446 47,972 21,553 — — 1,171,971 Residential real estate: One- to four- family first liens 340,446 2,776 9,004 — — 352,226 One- to four- family junior liens 114,763 952 1,489 — — 117,204 Total residential real estate 455,209 3,728 10,493 — — 469,430 Consumer 36,059 — 68 31 — 36,158 Total $ 2,127,454 $ 96,842 $ 62,362 $ 37 $ — $ 2,286,695
Impaired Financing Receivables [Table Text Block]	The following table presents loans individually evaluated for impairment, excluding purchased credit impaired loans, by class of loan, as of March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 Recorded Investment Unpaid Principal Balance Related Allowance Recorded Investment Unpaid Principal Balance Related Allowance (in thousands) With no related allowance recorded: Agricultural $ 8,764 $ 9,264 $ — $ 1,523 $ 2,023 $ — Commercial and industrial 3,781 4,147 — 7,588 7,963 — Commercial real estate: Construction and development 84 84 — 84 84 — Farmland 3,952 3,952 — 287 287 — Multifamily 826 826 — — — — Commercial real estate-other 6,806 7,312 — 5,746 6,251 — Total commercial real estate 11,668 12,174 — 6,117 6,622 — Residential real estate: One- to four- family first liens 2,591 2,634 — 2,449 2,482 — One- to four- family junior liens 292 293 — 26 26 — Total residential real estate 2,883 2,927 — 2,475 2,508 — Consumer — — — — — — Total $ 27,096 $ 28,512 $ — $ 17,703 $ 19,116 $ — With an allowance recorded: Agricultural $ 2,181 $ 2,181 $ 580 $ 1,446 $ 1,446 $ 140 Commercial and industrial 7,118 7,207 1,708 2,146 2,177 1,126 Commercial real estate: Construction and development — — — — — — Farmland 2,092 2,092 676 — — — Multifamily — — — — — — Commercial real estate-other 3,688 11,320 2,662 4,269 11,536 2,157 Total commercial real estate 5,780 13,412 3,338 4,269 11,536 2,157 Residential real estate: One- to four- family first liens 972 972 167 979 979 185 One- to four- family junior liens — — — 268 268 41 Total residential real estate 972 972 167 1,247 1,247 226 Consumer — — — — — — Total $ 16,051 $ 23,772 $ 5,793 $ 9,108 $ 16,406 $ 3,649 Total: Agricultural $ 10,945 $ 11,445 $ 580 $ 2,969 $ 3,469 $ 140 Commercial and industrial 10,899 11,354 1,708 9,734 10,140 1,126 Commercial real estate: Construction and development 84 84 — 84 84 — Farmland 6,044 6,044 676 287 287 — Multifamily 826 826 — — — — Commercial real estate-other 10,494 18,632 2,662 10,015 17,787 2,157 Total commercial real estate 17,448 25,586 3,338 10,386 18,158 2,157 Residential real estate: One- to four- family first liens 3,563 3,606 167 3,428 3,461 185 One- to four- family junior liens 292 293 — 294 294 41 Total residential real estate 3,855 3,899 167 3,722 3,755 226 Consumer — — — — — — Total $ 43,147 $ 52,284 $ 5,793 $ 26,811 $ 35,522 $ 3,649 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: Three Months Ended March 31, 2018 2017 Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized (in thousands) With no related allowance recorded: Agricultural $ 5,015 $ 124 $ 2,230 $ 13 Commercial and industrial 3,189 46 12,431 72 Commercial real estate: Construction and development 84 — 1,064 — Farmland 1,976 39 2,535 26 Multifamily 413 10 — — Commercial real estate-other 5,930 67 3,248 — Total commercial real estate 8,403 116 6,847 26 Residential real estate: One- to four- family first liens 1,602 — 2,563 — One- to four- family junior liens 293 — 13 — Total residential real estate 1,895 — 2,576 — Consumer — — — — Total $ 18,502 $ 286 $ 24,084 $ 111 With an allowance recorded: Agricultural $ 1,946 $ 17 $ 2,087 $ — Commercial and industrial 7,088 — 4,812 20 Commercial real estate: Construction and development — — 434 — Farmland 1,046 27 — — Multifamily — — — — Commercial real estate-other 4,141 — 6,369 — Total commercial real estate 5,187 27 6,803 — Residential real estate: One- to four- family first liens 976 9 1,400 9 One- to four- family junior liens — — — — Total residential real estate 976 9 1,400 9 Consumer — — — — Total $ 15,197 $ 53 $ 15,102 $ 29 Total: Agricultural $ 6,961 $ 141 $ 4,317 $ 13 Commercial and industrial 10,277 46 17,243 92 Commercial real estate: Construction and development 84 — 1,498 — Farmland 3,022 66 2,535 26 Multifamily 413 10 — — Commercial real estate-other 10,071 67 9,617 — Total commercial real estate 13,590 143 13,650 26 Residential real estate: One- to four- family first liens 2,578 9 3,963 9 One- to four- family junior liens 293 — 13 — Total residential real estate 2,871 9 3,976 9 Consumer — — — — Total $ 33,699 $ 339 $ 39,186 $ 140
Past Due Financing Receivables [Table Text Block]	The following table presents the contractual aging of the recorded investment in past due loans by class of loans at March 31, 2018 and December 31, 2017 : 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) March 31, 2018 Agricultural $ 1,722 $ 175 $ 138 $ 2,035 $ 109,940 $ 111,975 Commercial and industrial 5,523 136 1,599 7,258 506,520 513,778 Commercial real estate: Construction and development 11 — 177 188 194,524 194,712 Farmland 363 — — 363 86,667 87,030 Multifamily — — — — 126,802 126,802 Commercial real estate-other 2,778 48 1,081 3,907 785,995 789,902 Total commercial real estate 3,152 48 1,258 4,458 1,193,988 1,198,446 Residential real estate: One- to four- family first liens 2,968 444 1,177 4,589 345,153 349,742 One- to four- family junior liens 244 30 356 630 115,557 116,187 Total residential real estate 3,212 474 1,533 5,219 460,710 465,929 Consumer 58 15 19 92 35,938 36,030 Total $ 13,667 $ 848 $ 4,547 $ 19,062 $ 2,307,096 $ 2,326,158 Included in the totals above are the following purchased credit impaired loans $ — $ 206 $ 340 $ 546 $ 18,488 $ 19,034 December 31, 2017 Agricultural $ 95 $ 118 $ 168 $ 381 $ 105,131 $ 105,512 Commercial and industrial 1,434 1,336 1,576 4,346 499,278 503,624 Commercial real estate: Construction and development 57 97 82 236 165,040 165,276 Farmland 217 — 373 590 87,278 87,868 Multifamily — 25 — 25 134,481 134,506 Commercial real estate-other 74 — 1,852 1,926 782,395 784,321 Total commercial real estate 348 122 2,307 2,777 1,169,194 1,171,971 Residential real estate: One- to four- family first liens 3,854 756 1,019 5,629 346,597 352,226 One- to four- family junior liens 325 770 271 1,366 115,838 117,204 Total residential real estate 4,179 1,526 1,290 6,995 462,435 469,430 Consumer 79 15 29 123 36,035 36,158 Total $ 6,135 $ 3,117 $ 5,370 $ 14,622 $ 2,272,073 $ 2,286,695 Included in the totals above are the following purchased credit impaired loans $ 164 $ 756 $ 553 $ 1,473 $ 18,258 $ 19,731
Schedule of Financing Receivables, Non Accrual Status [Table Text Block]	The following table sets forth the composition of the Company’s recorded investment in loans on nonaccrual status and past due 90 days or more and still accruing by class of loans, excluding purchased credit impaired loans, as of March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 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 $ 390 $ — $ 168 $ — Commercial and industrial 7,125 — 7,124 — Commercial real estate: Construction and development 186 — 188 — Farmland 140 — 386 — Multifamily — — — — Commercial real estate-other 3,924 — 5,279 — Total commercial real estate 4,250 — 5,853 — Residential real estate: One- to four- family first liens 1,312 103 1,228 205 One- to four- family junior liens 434 13 346 2 Total residential real estate 1,746 116 1,574 207 Consumer 55 — 65 — Total $ 13,566 $ 116 $ 14,784 $ 207
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 three months ended March 31, 2018 and 2017 : Three Months Ended March 31, 2018 2017 (in thousands) Balance at beginning of period $ 840 $ 1,961 Accretion (277 ) (416 ) Reclassification from nonaccretable difference 45 88 Balance at end of period $ 608 $ 1,633

Derivative and Hedging Activi28

Derivative and Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments [Table Text Block]	As of March 31, 2018 , the Company had the following outstanding interest rate derivatives that were used to hedge changes in fair value attributable to interest rate risk: Interest Rate Derivative Number of Instruments Notional (dollars in thousands) Interest Rate Swaps 1 4,354 As of March 31, 2018 , the following amounts were recorded on the balance sheet related to cumulative basis adjustment for fair value hedges: Line Item in the Balance Sheet in Which the Hedged Item is Included Carrying Amount of the Hedged Assets Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Asset (in thousands) Loans 4,516 161
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]	The table below presents the fair value of the Company’s derivative financial instruments as well as their classification on the Consolidated Balance Sheet as of March 31, 2018 and December 31, 2017 : Fair Values of Derivative Instruments As of March 31, 2018 As of December 31, 2017 (in thousands) Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments: Interest rate products Other Liabilities 161 N/A —
Derivative Instruments, Gain (Loss) [Table Text Block]	The table below presents the effect of the Company’s derivative financial instruments on the Consolidated Statements of Operations for the three months ended March 31, 2018 and March 31, 2017 : Location and Amount of Gain or Loss Recognized in Income on Fair Value Hedging Relationships For the Three Months Ended March 31, 2018 2017 (in thousands) Interest Income (Expense) Other Gain (Loss) Interest Income (Expense) Other Gain (Loss) Total amounts of income and expense line items presented in the Consolidated Statements of Operation in which the effects of fair value hedges are recorded (1 ) — — — The effects of fair value hedging: Loss on fair value hedging relationships in subtopic 815-20: Interest contracts: Hedged items (162 ) — — — Derivative designated as hedging instruments 161 — — —
Offsetting Liabilities [Table Text Block]	The table below presents a gross presentation, the effects of offsetting, and a net presentation of the Company’s derivatives as of March 31, 2018 and December 31, 2017 . The net amounts of derivative assets or liabilities can be reconciled to the tabular disclosure of fair value. The tabular disclosure of fair value provides the location that derivative assets and liabilities are presented on the Balance Sheet. Offsetting of Derivative Assets Gross Amounts Not Offset in the Balance Sheet (in thousands) Gross Amounts of Recognized Assets (Liabilities) Gross Amounts Offset in the Balance Sheet Net Amounts of Assets (Liabilities) presented in the Balance Sheet Financial Instruments Cash Collateral Received (Paid) Net Assets (Liabilities) As of March 31, 2018 Derivatives (161 ) — (161 ) — (130 ) (31 ) As of December 31, 2017 Derivatives — — — — — —

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2018
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, and net book value as of and for the three months ended March 31, 2018 : Insurance Agency Intangible Core Deposit Intangible Indefinite-Lived Trade Name Intangible Finite-Lived Trade Name Intangible Customer List Intangible Total (in thousands) March 31, 2018 Balance, beginning of period $ 148 $ 4,011 $ 7,040 $ 744 $ 103 $ 12,046 Amortization expense (9 ) (594 ) — (50 ) (4 ) (657 ) Balance at end of period $ 139 $ 3,417 $ 7,040 $ 694 $ 99 $ 11,389 Gross carrying amount $ 1,320 $ 18,206 $ 7,040 $ 1,380 $ 330 $ 28,276 Accumulated amortizations (1,181 ) (14,789 ) — (686 ) (231 ) (16,887 ) Net book value $ 139 $ 3,417 $ 7,040 $ 694 $ 99 $ 11,389

Other Assets (Tables)

Other Assets (Tables)	3 Months Ended
	Mar. 31, 2018
Other Assets [Abstract]
Schedule of Other Assets [Table Text Block]	The components of the Company’s other assets were as follows: March 31, 2018 December 31, 2017 (in thousands) Federal Home Loan Bank Stock $ 12,780 $ 11,324 Prepaid expenses 2,067 2,992 Mortgage servicing rights 2,536 2,316 Federal & state income taxes receivable, current 897 3,120 Accounts receivable & other miscellaneous assets 4,479 3,009 $ 22,759 $ 22,761

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	3 Months Ended
	Mar. 31, 2018
Short-term Debt [Abstract]
Schedule of Short-term Debt [Table Text Block]	Short-term borrowings were as follows as of March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 (in thousands) Weighted Average Cost Balance Weighted Average Cost Balance Federal funds purchased 1.95 % $ 25,573 1.77 % $ 1,000 Securities sold under agreements to repurchase 0.72 67,738 0.71 96,229 Total 1.06 % $ 93,311 0.73 % $ 97,229

Subordinated Notes Payable (Tab

Subordinated Notes Payable (Tables)	3 Months Ended
	Mar. 31, 2018
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 March 31, 2018 and December 31, 2017 : Face Value Book Value Interest Rate Interest Rate at Maturity Date Callable Date (in thousands) 3/31/2018 March 31, 2018 Central Bancshares Capital Trust II (1) (2) $ 7,217 $ 6,688 Three-month LIBOR + 3.50% 5.62 % 03/15/2038 03/15/2013 Barron Investment Capital Trust I (1) (2) 2,062 1,665 Three-month LIBOR + 2.15% 4.42 % 09/23/2036 09/23/2011 MidWestOne Statutory Trust II (1) 15,464 15,464 Three-month LIBOR + 1.59% 3.71 % 12/15/2037 12/15/2012 Total $ 24,743 $ 23,817 Face Value Book Value Interest Rate Interest Rate at Maturity Date Callable Date (in thousands) 12/31/2017 December 31, 2017 Central Bancshares Capital Trust II (1) (2) $ 7,217 $ 6,674 Three-month LIBOR + 3.50% 5.09 % 03/15/2038 03/15/2013 Barron Investment Capital Trust I (1) (2) 2,062 1,655 Three-month LIBOR + 2.15% 3.82 % 09/23/2036 09/23/2011 MidWestOne Statutory Trust II (1) 15,464 15,464 Three-month LIBOR + 1.59% 3.18 % 12/15/2037 12/15/2012 Total $ 24,743 $ 23,793 (1) All distributions are cumulative and paid in cash quarterly. (2) Central Bancshares Capital Trust II and Barron Investment Capital Trust I were established by Central prior to the Company’s merger with Central, and the junior subordinated notes issued by Central were assumed by the Company.

Long-Term Borrowings (Tables)

Long-Term Borrowings (Tables)	3 Months Ended
	Mar. 31, 2018
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 March 31, 2018 and December 31, 2017 : March 31, 2018 December 31, 2017 (in thousands) Weighted Average Cost Balance Weighted Average Cost Balance FHLB Borrowings 1.93 % $ 123,000 1.72 % $ 115,000 Note payable to unaffiliated bank 3.41 11,250 3.32 12,500 Total 2.05 % $ 134,250 1.88 % $ 127,500

Income Taxes (Tables)

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	The income tax provisions for the three months ended March 31, 2018 and 2017 were less than the amounts computed by applying the maximum effective federal income tax rate of 21% and 35% , respectively, to the income before income taxes, because of the following items: For the Three Months Ended March 31, 2018 2017 (in thousands) Amount % of Pretax Income Amount % of Pretax Income Expected provision $ 2,053 21.0 % $ 3,235 35.0 % Tax-exempt interest (490 ) (5.0 ) (786 ) (8.5 ) Bank-owned life insurance (91 ) (0.9 ) (115 ) (1.2 ) State income taxes, net of federal income tax benefit 529 5.4 405 4.4 General business credits (47 ) (0.8 ) (21 ) (0.2 ) Other 30 0.6 (189 ) (2.1 ) Total income tax provision $ 1,984 20.3 % $ 2,529 27.4 %

Earnings per Share (Tables)

Earnings per Share (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table Text Block]	The following table presents the computation of earnings per common share for the respective periods: Three Months Ended March 31, (dollars in thousands, except per share amounts) 2018 2017 Basic earnings per common share computation Numerator: Net income $ 7,793 $ 6,713 Denominator: Weighted average shares outstanding 12,222,690 11,505,687 Basic earnings per common share $ 0.64 $ 0.58 Diluted earnings per common share computation Numerator: Net income $ 7,793 $ 6,713 Denominator: Weighted average shares outstanding, including all dilutive potential shares 12,241,714 11,555,356 Diluted earnings per common share $ 0.64 $ 0.58

Estimated Fair Value of Finan36

Estimated Fair Value of Financial Instruments and Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The following table summarizes assets and liabilities measured at fair value on a recurring basis as of March 31, 2018 and December 31, 2017 . The assets and liabilities are segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value: Fair Value Measurement at March 31, 2018 Using (in thousands) Fair Value 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. Government agencies and corporations $ 15,399 $ — $ 15,399 $ — State and political subdivisions 147,526 — 147,526 — Mortgage-backed securities 47,260 — 47,260 — Collateralized mortgage obligations 170,805 — 170,805 — Corporate debt securities 65,097 — 65,097 — Total available for sale debt securities $ 446,087 $ — $ 446,087 $ — Liabilities: Derivatives $ 161 $ — $ 161 $ — Fair Value Measurement at December 31, 2017 Using (in thousands) Fair Value 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. Government agencies and corporations $ 15,626 $ — $ 15,626 $ — State and political subdivisions 141,839 — 141,839 — Mortgage-backed securities 48,497 — 48,497 — Collateralized mortgage obligations 168,196 — 168,196 — Corporate debt securities 71,166 — 71,166 — Total available for sale debt securities $ 445,324 $ — $ 445,324 $ — Other equity securities 2,336 2,336 — — Total securities available for sale $ 447,660 $ 2,336 $ 445,324 $ —
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [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 March 31, 2018 and December 31, 2017 , as more fully described above. Fair Value Measurement at March 31, 2018 Using (in thousands) Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Collateral dependent impaired loans $ 8,877 $ — $ — $ 8,877 Other real estate owned $ 1,001 $ — $ — $ 1,001 Fair Value Measurement at December 31, 2017 Using (in thousands) Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Collateral dependent impaired loans $ 3,927 $ — $ — $ 3,927 Other real estate owned $ 2,010 $ — $ — $ 2,010
Fair Value, by Balance Sheet Grouping [Table Text Block]	Due to the adoption of ASU 2016-01 as of January 1, 2018, the estimated fair value amounts shown for December 31, 2017 are not comparable to those for March 31, 2018 , due to a change in the required methodology (“exit price” only) for determining current estimated fair value. The carrying amount and estimated fair value of financial instruments not carried at fair value, at March 31, 2018 and December 31, 2017 are as follows: March 31, 2018 Carrying Amount Estimated Fair Value Quoted Significant Other Significant (in thousands) Financial assets: Cash and cash equivalents $ 42,396 $ 42,396 $ 42,396 $ — $ — Investment securities: Equity securities 2,815 2,815 2,815 — — Available for sale debt securities 446,087 446,087 — 446,087 — Held to maturity debt securities 194,617 190,593 — 190,593 — Total investment securities 643,519 639,495 2,815 636,680 — Loans held for sale 870 895 — 895 — Loans, net 2,296,487 2,247,398 — — 2,247,398 Accrued interest receivable 13,337 13,337 13,337 — — Federal Home Loan Bank stock 12,780 12,780 — 12,780 — Financial liabilities: Deposits: Non-interest bearing demand 450,168 450,168 450,168 — — Interest-bearing checking 1,240,208 1,240,208 1,240,208 — — Savings 215,940 215,940 215,940 — — Certificates of deposit under $100,000 332,727 328,009 — 328,009 — Certificates of deposit $100,000 and over 392,878 389,430 — 389,430 — Total deposits 2,631,921 2,623,755 1,906,316 717,439 — Federal funds purchased and securities sold under agreements to repurchase 93,311 93,311 93,311 — — Federal Home Loan Bank borrowings 123,000 120,850 — 120,850 — Junior subordinated notes issued to capital trusts 23,817 21,032 — 21,032 — Long-term debt 11,250 11,250 — 11,250 — Derivative liability 161 161 — 161 — December 31, 2017 Carrying Amount Estimated Fair Value Quoted Prices in Markets for Significant Other Significant (in thousands) Financial assets: Cash and cash equivalents $ 50,972 $ 50,972 $ 50,972 $ — $ — Investment securities: Equity securities 2,336 2,336 2,336 — — Available for sale debt securities 445,324 445,324 — 445,324 — Held to maturity debt securities 195,619 194,343 — 194,343 — Total investment securities 643,279 642,003 2,336 639,667 — Loans held for sale 856 871 — — 871 Loans, net 2,258,636 2,256,726 — 2,256,726 — Accrued interest receivable 14,732 14,732 14,732 — — Federal Home Loan Bank stock 11,324 11,324 — 11,324 — Financial liabilities: Deposits: Non-interest bearing demand 461,969 461,969 461,969 — — Interest-bearing checking 1,228,112 1,228,112 1,228,112 — — Savings 213,430 213,430 213,430 — — Certificates of deposit under $100,000 324,681 321,197 — 321,197 — Certificates of deposit $100,000 and over 377,127 374,685 — 374,685 — Total deposits 2,605,319 2,599,393 1,903,511 695,882 — Federal funds purchased and securities sold under agreements to repurchase 97,229 97,229 97,229 — — Federal Home Loan Bank borrowings 115,000 114,945 — 114,945 — Junior subordinated notes issued to capital trusts 23,793 19,702 — 19,702 — Long-term debt 12,500 12,500 — 12,500 —
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Table Text Block]	The following presents the valuation technique(s), unobservable inputs, and quantitative information about the unobservable inputs used for fair value measurements of the financial instruments held by the Company at March 31, 2018 , categorized within Level 3 of the fair value hierarchy: Quantitative Information About Level 3 Fair Value Measurements (dollars in thousands) Fair Value at March 31, 2018 Valuation Techniques(s) Unobservable Input Range of Inputs Weighted Average Collateral dependent impaired loans $ 8,877 Modified appraised value Third party appraisal NM * - NM * NM * Appraisal discount NM * - NM * NM * Other real estate owned $ 1,001 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.

Investment Securities Schedule

Investment Securities Schedule of Available for Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities
Amortized cost basis	$ 454,482	$ 451,190
Gross unrealized gains	1,848	2,840
Gross unrealized losses	10,243	6,370
Estimated fair value	446,087	447,660
U.S. Government agencies and corporations
Schedule of Available-for-sale Securities
Amortized cost basis	15,678	15,716
Gross unrealized gains	0	0
Gross unrealized losses	279	90
Estimated fair value	15,399	15,626
State and political subdivisions
Schedule of Available-for-sale Securities
Amortized cost basis	146,386	139,561
Gross unrealized gains	1,663	2,475
Gross unrealized losses	523	197
Estimated fair value	147,526	141,839
Mortgage-backed securities
Schedule of Available-for-sale Securities
Amortized cost basis	48,065	48,744
Gross unrealized gains	147	181
Gross unrealized losses	952	428
Estimated fair value	47,260	48,497
Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Amortized cost basis	178,068	173,339
Gross unrealized gains	13	29
Gross unrealized losses	7,276	5,172
Estimated fair value	170,805	168,196
Corporate debt securities
Schedule of Available-for-sale Securities
Amortized cost basis	66,285	71,562
Gross unrealized gains	25	31
Gross unrealized losses	1,213	427
Estimated fair value	$ 65,097	71,166
Debt securities
Schedule of Available-for-sale Securities
Amortized cost basis		448,922
Gross unrealized gains		2,716
Gross unrealized losses		6,314
Estimated fair value		445,324
Equity securities
Schedule of Available-for-sale Securities
Amortized cost basis		2,268
Gross unrealized gains		124
Gross unrealized losses		56
Estimated fair value		$ 2,336

Investment Securities Schedul38

Investment Securities Schedule of Held to Maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Held-to-maturity Securities
Held to maturity securities, amortized cost	$ 194,617	$ 195,619
Gross unrealized gains	821	1,356
Gross unrealized losses	4,845	2,632
Estimated fair value	190,593	194,343
U.S. Government agencies and corporations
Schedule of Held-to-maturity Securities
Held to maturity securities, amortized cost	10,047	10,049
Gross unrealized losses	278
Estimated fair value	9,769	10,049
State and political subdivisions
Schedule of Held-to-maturity Securities
Held to maturity securities, amortized cost	126,356	126,413
Gross unrealized gains	315	804
Gross unrealized losses	3,089	1,631
Estimated fair value	123,582	125,586
Mortgage-backed securities
Schedule of Held-to-maturity Securities
Held to maturity securities, amortized cost	1,882	1,906
Gross unrealized gains	2	4
Gross unrealized losses	45	13
Estimated fair value	1,839	1,897
Collateralized mortgage obligations
Schedule of Held-to-maturity Securities
Held to maturity securities, amortized cost	21,204	22,115
Gross unrealized losses	932	707
Estimated fair value	20,272	21,408
Corporate debt securities
Schedule of Held-to-maturity Securities
Held to maturity securities, amortized cost	35,128	35,136
Gross unrealized gains	504	548
Gross unrealized losses	501	281
Estimated fair value	$ 35,131	$ 35,403

Investment Securities Available

Investment Securities Available for Sale Securities in Continuous Loss Position (Details) $ in Thousands	Mar. 31, 2018USD ($)count	Dec. 31, 2017USD ($)count
Schedule of Available-for-sale Securities
Available for sale securities in unrealized loss positions, number of positions | count	149	105
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 187,166	$ 158,516
Available for sale securities, continuous unrealized loss position, less than 12 months, Accumulated Loss	3,607	1,403
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	132,794	139,240
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	6,636	4,967
Available for sale securities, continuous unrealized loss position, fair value	319,960	297,756
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 10,243	$ 6,370
U.S. Government agencies and corporations
Schedule of Available-for-sale Securities
Available for sale securities in unrealized loss positions, number of positions | count	3	3
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 15,399	$ 15,626
Available for sale securities, continuous unrealized loss position, less than 12 months, Accumulated Loss	279	90
Available for sale securities, continuous unrealized loss position, fair value	15,399	15,626
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 279	$ 90
State and political subdivisions
Schedule of Available-for-sale Securities
Available for sale securities in unrealized loss positions, number of positions | count	72	34
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 33,470	$ 11,705
Available for sale securities, continuous unrealized loss position, less than 12 months, Accumulated Loss	452	167
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	2,757	1,800
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	71	30
Available for sale securities, continuous unrealized loss position, fair value	36,227	13,505
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 523	$ 197
Mortgage-backed securities
Schedule of Available-for-sale Securities
Available for sale securities in unrealized loss positions, number of positions | count	21	20
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 36,330	$ 37,964
Available for sale securities, continuous unrealized loss position, less than 12 months, Accumulated Loss	871	359
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	3,627	3,961
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	81	69
Available for sale securities, continuous unrealized loss position, fair value	39,957	41,925
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 952	$ 428
Collateralized mortgage obligations
Schedule of Available-for-sale Securities
Available for sale securities in unrealized loss positions, number of positions | count	41	35
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 47,328	$ 37,881
Available for sale securities, continuous unrealized loss position, less than 12 months, Accumulated Loss	1,010	489
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	117,834	122,757
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	6,266	4,683
Available for sale securities, continuous unrealized loss position, fair value	165,162	160,638
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 7,276	$ 5,172
Corporate debt securities
Schedule of Available-for-sale Securities
Available for sale securities in unrealized loss positions, number of positions | count	12	12
Available for sale securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 54,639	$ 55,340
Available for sale securities, continuous unrealized loss position, less than 12 months, Accumulated Loss	995	298
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value	8,576	8,778
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss	218	129
Available for sale securities, continuous unrealized loss position, fair value	63,215	64,118
Available for sale securities, continuous unrealized loss position, accumulated loss	$ 1,213	$ 427
Equity securities
Schedule of Available-for-sale Securities
Available for sale securities in unrealized loss positions, number of positions | count		1
Available for sale securities, continuous unrealized loss position, twelve months or longer, estimated fair value		$ 1,944
Available for sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss		56
Available for sale securities, continuous unrealized loss position, fair value		1,944
Available for sale securities, continuous unrealized loss position, accumulated loss		$ 56

Investment Securities Held to M

Investment Securities Held to Maturity Securities in Continuous Loss Position (Details) $ in Thousands	Mar. 31, 2018USD ($)count	Dec. 31, 2017USD ($)count
Schedule of Held-to-maturity Securities
Held to maturity securities in unrealized loss positions, number of positions | count	245	181
Held to maturity securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 79,794	$ 41,900
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	1,882	489
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value	43,978	45,515
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss	2,963	2,143
Held to maturity securities, continuous urealized loss position, fair value	123,772	87,415
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 4,845	$ 2,632
U.S. Government agencies and corporations
Schedule of Held-to-maturity Securities
Held to maturity securities in unrealized loss positions, number of positions | count	1
Held to maturity securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 9,769
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	278
Held to maturity securities, continuous urealized loss position, fair value	9,769
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 278
State and political subdivisions
Schedule of Held-to-maturity Securities
Held to maturity securities in unrealized loss positions, number of positions | count	227	167
Held to maturity securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 52,946	$ 33,237
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	1,212	393
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value	25,191	25,843
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss	1,877	1,238
Held to maturity securities, continuous urealized loss position, fair value	78,137	59,080
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 3,089	$ 1,631
Mortgage-backed securities
Schedule of Held-to-maturity Securities
Held to maturity securities in unrealized loss positions, number of positions | count	5	4
Held to maturity securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 902	$ 349
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	15	2
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value	857	887
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss	30	11
Held to maturity securities, continuous urealized loss position, fair value	1,759	1,236
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 45	$ 13
Collateralized mortgage obligations
Schedule of Held-to-maturity Securities
Held to maturity securities in unrealized loss positions, number of positions | count	7	7
Held to maturity securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 4,941	$ 5,221
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	155	90
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value	15,314	16,168
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss	777	617
Held to maturity securities, continuous urealized loss position, fair value	20,255	21,389
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 932	$ 707
Corporate debt securities
Schedule of Held-to-maturity Securities
Held to maturity securities in unrealized loss positions, number of positions | count	5	3
Held to maturity securities, continuous unrealized loss position, less than twelve months, estimated fair value	$ 11,236	$ 3,093
Held to maturity securities, continuous unrealized loss position, less than 12 months, accumulated loss	222	4
Held to maturity securities, continuous unrealized loss position, twelve months or longer, fair value	2,616	2,617
Held to maturity securities, continuous unrealized loss position, 12 months or longer, accumulated loss	279	277
Held to maturity securities, continuous urealized loss position, fair value	13,852	5,710
Held to maturity securities, continuous unrealized loss position, accumulated loss	$ 501	$ 281

Investment Securities Investmen

Investment Securities Investments Classified by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Rolling Maturity [Abstract]
Due in one year or less, amortized cost	$ 28,726
Due after one year through five years, amortized cost	116,063
Due after five years through ten years, amortized cost	70,509
Due after ten years, amortized cost	13,051
Debt securities without a single maturity date, amortized cost	226,133
Total available for sale securities, debt securities, amortized cost	454,482
Available-for-sale Securities, Debt Maturities, Fair Value, Rolling Maturity [Abstract]
Due in one year or less, estimated fair value	28,807
Due after one year through five years, estimated fair value	115,334
Due after five years through ten years, estimated fair value	71,045
Due after ten years, estimated fair value	12,836
Debt securities without a single maturity date, estimated fair value	218,065
Total available for sale securities, debt securities, estimated fair value	446,087	$ 445,324
Held-to-maturity Securities, Debt Maturities, Amortized Cost, Rolling Maturity [Abstract]
Due after one year through five years, amortized cost	18,777
Due after five years through ten years, amortized cost	91,309
Due after ten years, amortized cost	61,445
Debt securities without a single maturity date, amortized cost	23,086
Held to maturity securities, amortized cost	194,617	195,619
Held-to-maturity Securities, Debt Maturities, Fair Value, Rolling Maturity [Abstract]
Due after one year through five years, estimated fair value	18,573
Due after five years through ten years, estimated fair value	90,725
Due after ten years, estimated fair value	59,184
Debt securities without a single maturity date, estimated fair value	22,111
Fair value of investment securities held to maturity	$ 190,593	$ 194,343

Investment Securities Realized

Investment Securities Realized Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Held-to-maturity Securities [Abstract]
Gross realized gains	$ 0	$ 43
Marketable Securities, Equity Securities [Abstract]
Equity Securities, FV-NI, Realized Gain (Loss)	(24)
Gain (Loss) on Sale of Equity Investments	0
Equity Securities, FV-NI, Unrealized Gain (Loss)	(24)
Debt securities
Available-for-sale Securities [Abstract]
Gross realized gains	9	0
Gross realized losses	0	0
Other than Temporary Impairment	0	0
Available for sale securities, gross realized gain (loss)	9
Held-to-maturity Securities [Abstract]
Gross realized gains	$ 0	$ 43

Investment Securities Textual R

Investment Securities Textual References (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Schedule of Available-for-sale Securities
Available-for-sale securities pledged as collateral	$ 238,200		$ 237,400
Available for sale securities	446,087		447,660
Amortized cost basis	454,482		451,190
Proceeds from sales of available for sale securities	496
Proceeds from sales of held to maturity securities	0	$ 1,153
State and political subdivisions
Schedule of Available-for-sale Securities
Available for sale securities	147,526		141,839
Amortized cost basis	146,386		139,561
Corporate debt securities
Schedule of Available-for-sale Securities
Available for sale securities	65,097		71,166
Amortized cost basis	66,285		71,562
Other equity securities
Schedule of Available-for-sale Securities
Available for sale securities			2,336
Amortized cost basis			2,268
Other equity securities | Banks and Financial Service-Related Companies
Schedule of Available-for-sale Securities
Available for sale securities	400
Community Reinvestment Act qualified investment
Schedule of Available-for-sale Securities
Available for sale securities	2,400
Debt securities
Schedule of Available-for-sale Securities
Available for sale securities			445,324
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net, Available-for-sale Securities	0	0
Amortized cost basis			$ 448,922
Proceeds from sales of available for sale securities		0
Available for sale securities, gross realized gains	$ 9	$ 0
Geographic Concentration Risk | Total Obligations of State and Political Subdivisions | State and political subdivisions | IOWA
Schedule of Available-for-sale Securities
Concentration risk, percentage	56.00%
Geographic Concentration Risk | Total Obligations of State and Political Subdivisions | State and political subdivisions | MINNESOTA
Schedule of Available-for-sale Securities
Concentration risk, percentage	22.00%

Loans Receivable and the Allo44

Loans Receivable and the Allowance for Loan Losses Allowance for Loan Losses and Recorded Investment in Loan Receivables (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	$ 5,793	$ 3,649
Loans receivable, allowance for credit losses, collectively evaluated for impairment	23,171	23,612
Certain loans acquired in transfer not accounted for as debt securities, allowance for loan losses		798
Allowance for loan losses	29,671	28,059	$ 22,217	$ 21,850
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	43,147	26,811
Loans receivable, collectively evaluated for impairment	2,263,977	2,240,153
Loans receivable,purchased credit impaired		19,731
Loans and leases receivable, gross	2,326,158	2,286,695
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	707
Financing Receivable [Abstract]
Loans receivable,purchased credit impaired	19,034
Agricultural Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	580	140
Loans receivable, allowance for credit losses, collectively evaluated for impairment	2,573	2,650
Allowance for loan losses	3,153	2,790	2,460	2,003
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	10,945	2,969
Loans receivable, collectively evaluated for impairment	101,030	102,543
Loans and leases receivable, gross	111,975	105,512
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	1,708	1,126
Loans receivable, allowance for credit losses, collectively evaluated for impairment	6,654	7,392
Allowance for loan losses	8,362	8,518	6,021	6,274
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	10,899	9,734
Loans receivable, collectively evaluated for impairment	502,824	493,844
Loans and leases receivable, gross	513,778	503,624
Commercial Portfolio Segment | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable [Abstract]
Loans receivable,purchased credit impaired	55	46
Commercial Real Estate Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	3,338	2,157
Loans receivable, allowance for credit losses, collectively evaluated for impairment	11,408	11,144
Allowance for loan losses	14,997	13,637	9,751	9,860
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	17,448	10,386
Loans receivable, collectively evaluated for impairment	1,166,913	1,147,133
Loans and leases receivable, gross	1,198,446	1,171,971
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	251	336
Financing Receivable [Abstract]
Loans receivable,purchased credit impaired	14,085	14,452
Residential Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, individually evaluated for impairment	167	226
Loans receivable, allowance for credit losses, collectively evaluated for impairment	2,254	2,182
Allowance for loan losses	2,877	2,870	3,764	3,458
Financing Receivable [Abstract]
Loans receivable, individually evaluated for impairment	3,855	3,722
Loans receivable, collectively evaluated for impairment	457,180	460,475
Loans and leases receivable, gross	465,929	469,430
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	456	462
Financing Receivable [Abstract]
Loans receivable,purchased credit impaired	4,894	5,233
Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivable, allowance for credit losses, collectively evaluated for impairment	282	244
Allowance for loan losses	282	244	$ 221	$ 255
Financing Receivable [Abstract]
Loans receivable, collectively evaluated for impairment	36,030	36,158
Loans and leases receivable, gross	$ 36,030	$ 36,158

Loans Receivable and the Allo45

Loans Receivable and the Allowance for Loan Losses Allowance for Loan Loss Activity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 28,059	$ 21,850
Charge-offs	(476)	(716)
Recoveries	238	42
Provision	1,850	1,041
Ending balance	29,671	22,217
Agricultural Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	2,790	2,003
Charge-offs		(537)
Recoveries	6	10
Provision	357	984
Ending balance	3,153	2,460
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	8,518	6,274
Charge-offs	(87)	(65)
Recoveries	79	19
Provision	(148)	(207)
Ending balance	8,362	6,021
Commercial Real Estate Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	13,637	9,860
Charge-offs	(264)	(61)
Recoveries	76	10
Provision	1,548	(58)
Ending balance	14,997	9,751
Residential Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	2,870	3,458
Charge-offs	(104)	(28)
Recoveries	62
Provision	49	334
Ending balance	2,877	3,764
Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	244	255
Charge-offs	(21)	(25)
Recoveries	15	3
Provision	44	(12)
Ending balance	$ 282	$ 221

Loans Receivable and the Allo46

Loans Receivable and the Allowance for Loan Losses New Troubled Debt Restructurings During Period (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)count
Financing Receivable, Modifications
Financing Receivable, Modifications, Number of Contracts | count	7
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 3,005
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 3,051
Commercial and Industrial Loan Financing Receivable | Extended Maturity
Financing Receivable, Modifications
Financing Receivable, Modifications, Number of Contracts | count	6	[1]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 2,037	[1]
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 2,083	[1]
Commercial Real Estate Portfolio Segment | Commercial Real Estate Loan Other Financing Receivable | Extended Maturity
Financing Receivable, Modifications
Financing Receivable, Modifications, Number of Contracts | count	1	[1]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 968	[1]
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 968	[1]
[1]	TDRs may include multiple concessions, and the disclosure classifications are based on the primary concession provided to the borrower.

Loans Receivable and the Allo47

Loans Receivable and the Allowance for Loan Losses New Troubled Debt Restructurings During Past Twelve Months That Defaulted During the Period (Details) $ in Thousands		3 Months Ended
		Mar. 31, 2018USD ($)count	Mar. 31, 2017USD ($)count
Financing Receivable, Modifications
Financing receivable, modifications, subsequent default, number of contracts | count		1	3
Financing receivable, modifications, subsequent default, recorded investment | $		$ 2,657	$ 954
Commercial Portfolio Segment | Commercial and Industrial Loan Financing Receivable | Extended Maturity
Financing Receivable, Modifications
Financing receivable, modifications, subsequent default, number of contracts | count	[1]		3
Financing receivable, modifications, subsequent default, recorded investment | $	[1]		$ 954
Commercial Real Estate Portfolio Segment | Commercial Real Estate Loan Other Financing Receivable | Extended Maturity
Financing Receivable, Modifications
Financing receivable, modifications, subsequent default, number of contracts | count	[1]	1
Financing receivable, modifications, subsequent default, recorded investment | $	[1]	$ 2,657
[1]	TDRs may include multiple concessions, and the disclosure classifications are based on the primary concession provided to the borrower.

Loans Receivable and the Allo48

Loans Receivable and the Allowance for Loan Losses Loans by Internally Assigned Credit Quality Indicators (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment
Loans receivable, net	$ 2,326,158	$ 2,286,695
Purchased credit-impaired loans, internally classified as other than pass	12,000	12,600
Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	2,159,958	2,127,454
Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	97,921	96,842
Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	68,243	62,362
Internally Assigned Grade Doubtful
Financing Receivable, Recorded Investment
Loans receivable, net	36	37
Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	111,975	105,512
Agricultural Loan Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	80,471	80,377
Agricultural Loan Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	19,883	21,989
Agricultural Loan Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	11,621	3,146
Commercial and Industrial Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	513,778	503,624
Commercial and Industrial Loan Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	465,235	453,363
Commercial and Industrial Loan Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	30,574	23,153
Commercial and Industrial Loan Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	17,963	27,102
Commercial and Industrial Loan Financing Receivable | Internally Assigned Grade Doubtful
Financing Receivable, Recorded Investment
Loans receivable, net	6	6
Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	194,712	165,276
Commercial Real Estate Construction and Development Loan Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	192,384	162,968
Commercial Real Estate Construction and Development Loan Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	1,054	1,061
Commercial Real Estate Construction and Development Loan Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	1,274	1,247
Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	87,030	87,868
Farmland Loan Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	71,590	76,740
Farmland Loan Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	8,216	10,357
Farmland Loan Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	7,224	771
Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	126,802	134,506
Multifamily Real Estate Loan Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	124,203	131,507
Multifamily Real Estate Loan Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	1,417	2,498
Multifamily Real Estate Loan Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	1,182	501
Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	789,902	784,321
Commercial Real Estate Loan Other Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	737,765	731,231
Commercial Real Estate Loan Other Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	33,505	34,056
Commercial Real Estate Loan Other Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	18,632	19,034
Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	349,742	352,226
Residential Real Estate First Lien Loan Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	338,419	340,446
Residential Real Estate First Lien Loan Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	2,495	2,776
Residential Real Estate First Lien Loan Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	8,828	9,004
Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	116,187	117,204
Residential Real Estate Junior Lien Loan Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	114,074	114,763
Residential Real Estate Junior Lien Loan Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	641	952
Residential Real Estate Junior Lien Loan Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	1,472	1,489
Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	36,030	36,158
Consumer Loan Financing Receivable | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	35,817	36,059
Consumer Loan Financing Receivable | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	136
Consumer Loan Financing Receivable | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	47	68
Consumer Loan Financing Receivable | Internally Assigned Grade Doubtful
Financing Receivable, Recorded Investment
Loans receivable, net	30	31
Agricultural Portfolio Segment | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	111,975	105,512
Commercial Portfolio Segment | Commercial and Industrial Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	513,778	503,624
Commercial Real Estate Portfolio Segment
Financing Receivable, Recorded Investment
Loans receivable, net	1,198,446	1,171,971
Commercial Real Estate Portfolio Segment | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	1,125,942	1,102,446
Commercial Real Estate Portfolio Segment | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	44,192	47,972
Commercial Real Estate Portfolio Segment | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	28,312	21,553
Commercial Real Estate Portfolio Segment | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	194,712	165,276
Commercial Real Estate Portfolio Segment | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	87,030	87,868
Commercial Real Estate Portfolio Segment | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	126,802	134,506
Commercial Real Estate Portfolio Segment | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	789,902	784,321
Residential Portfolio Segment
Financing Receivable, Recorded Investment
Loans receivable, net	465,929	469,430
Residential Portfolio Segment | Internally Assigned Grade Pass
Financing Receivable, Recorded Investment
Loans receivable, net	452,493	455,209
Residential Portfolio Segment | Internally Assigned Grade Special Mention Watch
Financing Receivable, Recorded Investment
Loans receivable, net	3,136	3,728
Residential Portfolio Segment | Internally Assigned Grade Substandard
Financing Receivable, Recorded Investment
Loans receivable, net	10,300	10,493
Residential Portfolio Segment | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	349,742	352,226
Residential Portfolio Segment | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	116,187	117,204
Consumer Portfolio Segment | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment
Loans receivable, net	$ 36,030	$ 36,158

Loans Receivable and the Allo49

Loans Receivable and the Allowance for Loan Losses Amounts and Categories of Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	$ 27,096		$ 17,703
Impaired financing receivable, with no related allowance, unpaid principal balance	28,512		19,116
Impaired financing receivable, with related allowance, recorded investment	16,051		9,108
Impaired financing receivable, with related allowance, unpaid principal balance	23,772		16,406
Impaired financing receivable, related allowance	5,793		3,649
Impaired financing receivable, recorded investment	43,147		26,811
Impaired financing receivable, unpaid principal balance	52,284		35,522
Impaired financing receivable, with no related allowance, average recorded investment	18,502	$ 24,084
Impaired financing receivable, with no related allowance, interest income, accrual method	286	111
Impaired financing receivable, with related allowance, average recorded investment	15,197	15,102
Impaired financing receivable, with related allowance, interest income, accrual method	53	29
Impaired financing receivable, average recorded investment	33,699	39,186
Impaired financing receivable, interest income, accrual method	339	140
Loans and leases receivable, impaired, commitment to lend	0
Agricultural Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	8,764		1,523
Impaired financing receivable, with no related allowance, unpaid principal balance	9,264		2,023
Impaired financing receivable, with related allowance, recorded investment	2,181		1,446
Impaired financing receivable, with related allowance, unpaid principal balance	2,181		1,446
Impaired financing receivable, related allowance	580		140
Impaired financing receivable, with no related allowance, average recorded investment	5,015	2,230
Impaired financing receivable, with no related allowance, interest income, accrual method	124	13
Impaired financing receivable, with related allowance, average recorded investment	1,946	2,087
Impaired financing receivable, with related allowance, interest income, accrual method	17
Commercial and Industrial Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	3,781		7,588
Impaired financing receivable, with no related allowance, unpaid principal balance	4,147		7,963
Impaired financing receivable, with related allowance, recorded investment	7,118		2,146
Impaired financing receivable, with related allowance, unpaid principal balance	7,207		2,177
Impaired financing receivable, related allowance	1,708		1,126
Impaired financing receivable, with no related allowance, average recorded investment	3,189	12,431
Impaired financing receivable, with no related allowance, interest income, accrual method	46	72
Impaired financing receivable, with related allowance, average recorded investment	7,088	4,812
Impaired financing receivable, with related allowance, interest income, accrual method		20
Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	84		84
Impaired financing receivable, with no related allowance, unpaid principal balance	84		84
Impaired financing receivable, with no related allowance, average recorded investment	84	1,064
Impaired financing receivable, with related allowance, average recorded investment		434
Farmland Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	3,952		287
Impaired financing receivable, with no related allowance, unpaid principal balance	3,952		287
Impaired financing receivable, with related allowance, recorded investment	2,092
Impaired financing receivable, with related allowance, unpaid principal balance	2,092
Impaired financing receivable, related allowance	676
Impaired financing receivable, with no related allowance, average recorded investment	1,976	2,535
Impaired financing receivable, with no related allowance, interest income, accrual method	39	26
Impaired financing receivable, with related allowance, average recorded investment	1,046
Impaired financing receivable, with related allowance, interest income, accrual method	27
Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	826
Impaired financing receivable, with no related allowance, unpaid principal balance	826
Impaired financing receivable, with no related allowance, average recorded investment	413
Impaired financing receivable, with no related allowance, interest income, accrual method	10
Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	6,806		5,746
Impaired financing receivable, with no related allowance, unpaid principal balance	7,312		6,251
Impaired financing receivable, with related allowance, recorded investment	3,688		4,269
Impaired financing receivable, with related allowance, unpaid principal balance	11,320		11,536
Impaired financing receivable, related allowance	2,662		2,157
Impaired financing receivable, with no related allowance, average recorded investment	5,930	3,248
Impaired financing receivable, with no related allowance, interest income, accrual method	67
Impaired financing receivable, with related allowance, average recorded investment	4,141	6,369
Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	2,591		2,449
Impaired financing receivable, with no related allowance, unpaid principal balance	2,634		2,482
Impaired financing receivable, with related allowance, recorded investment	972		979
Impaired financing receivable, with related allowance, unpaid principal balance	972		979
Impaired financing receivable, related allowance	167		185
Impaired financing receivable, with no related allowance, average recorded investment	1,602	2,563
Impaired financing receivable, with related allowance, average recorded investment	976	1,400
Impaired financing receivable, with related allowance, interest income, accrual method	9	9
Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	292		26
Impaired financing receivable, with no related allowance, unpaid principal balance	293		26
Impaired financing receivable, with related allowance, recorded investment			268
Impaired financing receivable, with related allowance, unpaid principal balance			268
Impaired financing receivable, related allowance			41
Impaired financing receivable, with no related allowance, average recorded investment	293	13
Agricultural Portfolio Segment | Agricultural Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, related allowance	580		140
Impaired financing receivable, recorded investment	10,945		2,969
Impaired financing receivable, unpaid principal balance	11,445		3,469
Impaired financing receivable, average recorded investment	6,961	4,317
Impaired financing receivable, interest income, accrual method	141	13
Commercial Portfolio Segment | Commercial and Industrial Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, related allowance	1,708		1,126
Impaired financing receivable, recorded investment	10,899		9,734
Impaired financing receivable, unpaid principal balance	11,354		10,140
Impaired financing receivable, average recorded investment	10,277	17,243
Impaired financing receivable, interest income, accrual method	46	92
Commercial Real Estate Portfolio Segment
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	11,668		6,117
Impaired financing receivable, with no related allowance, unpaid principal balance	12,174		6,622
Impaired financing receivable, with related allowance, recorded investment	5,780		4,269
Impaired financing receivable, with related allowance, unpaid principal balance	13,412		11,536
Impaired financing receivable, related allowance	3,338		2,157
Impaired financing receivable, recorded investment	17,448		10,386
Impaired financing receivable, unpaid principal balance	25,586		18,158
Impaired financing receivable, with no related allowance, average recorded investment	8,403	6,847
Impaired financing receivable, with no related allowance, interest income, accrual method	116	26
Impaired financing receivable, with related allowance, average recorded investment	5,187	6,803
Impaired financing receivable, with related allowance, interest income, accrual method	27
Impaired financing receivable, average recorded investment	13,590	13,650
Impaired financing receivable, interest income, accrual method	143	26
Commercial Real Estate Portfolio Segment | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, recorded investment	84		84
Impaired financing receivable, unpaid principal balance	84		84
Impaired financing receivable, average recorded investment	84	1,498
Commercial Real Estate Portfolio Segment | Farmland Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, related allowance	676
Impaired financing receivable, recorded investment	6,044		287
Impaired financing receivable, unpaid principal balance	6,044		287
Impaired financing receivable, average recorded investment	3,022	2,535
Impaired financing receivable, interest income, accrual method	66	26
Commercial Real Estate Portfolio Segment | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, recorded investment	826
Impaired financing receivable, unpaid principal balance	826
Impaired financing receivable, average recorded investment	413
Impaired financing receivable, interest income, accrual method	10
Commercial Real Estate Portfolio Segment | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, related allowance	2,662		2,157
Impaired financing receivable, recorded investment	10,494		10,015
Impaired financing receivable, unpaid principal balance	18,632		17,787
Impaired financing receivable, average recorded investment	10,071	9,617
Impaired financing receivable, interest income, accrual method	67
Residential Portfolio Segment
Financing Receivable, Impaired
Impaired financing receivable, with no related allowance, recorded investment	2,883		2,475
Impaired financing receivable, with no related allowance, unpaid principal balance	2,927		2,508
Impaired financing receivable, with related allowance, recorded investment	972		1,247
Impaired financing receivable, with related allowance, unpaid principal balance	972		1,247
Impaired financing receivable, related allowance	167		226
Impaired financing receivable, recorded investment	3,855		3,722
Impaired financing receivable, unpaid principal balance	3,899		3,755
Impaired financing receivable, with no related allowance, average recorded investment	1,895	2,576
Impaired financing receivable, with related allowance, average recorded investment	976	1,400
Impaired financing receivable, with related allowance, interest income, accrual method	9	9
Impaired financing receivable, average recorded investment	2,871	3,976
Impaired financing receivable, interest income, accrual method	9	9
Residential Portfolio Segment | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, related allowance	167		185
Impaired financing receivable, recorded investment	3,563		3,428
Impaired financing receivable, unpaid principal balance	3,606		3,461
Impaired financing receivable, average recorded investment	2,578	3,963
Impaired financing receivable, interest income, accrual method	9	9
Residential Portfolio Segment | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Impaired
Impaired financing receivable, related allowance			41
Impaired financing receivable, recorded investment	292		294
Impaired financing receivable, unpaid principal balance	293		$ 294
Impaired financing receivable, average recorded investment	$ 293	$ 13

Loans Receivable and the Allo50

Loans Receivable and the Allowance for Loan Losses Past Due Loan Aging (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due
Loans past due	$ 19,062	$ 14,622
Loans current	2,307,096	2,272,073
Total Loans Receivable	2,326,158	2,286,695
Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	2,035	381
Loans current	109,940	105,131
Total Loans Receivable	111,975	105,512
Commercial and Industrial Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	7,258	4,346
Loans current	506,520	499,278
Total Loans Receivable	513,778	503,624
Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	188	236
Loans current	194,524	165,040
Total Loans Receivable	194,712	165,276
Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	363	590
Loans current	86,667	87,278
Total Loans Receivable	87,030	87,868
Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due		25
Loans current	126,802	134,481
Total Loans Receivable	126,802	134,506
Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	3,907	1,926
Loans current	785,995	782,395
Total Loans Receivable	789,902	784,321
Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	4,589	5,629
Loans current	345,153	346,597
Total Loans Receivable	349,742	352,226
Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	630	1,366
Loans current	115,557	115,838
Total Loans Receivable	116,187	117,204
Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	92	123
Loans current	35,938	36,035
Total Loans Receivable	36,030	36,158
Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	546	1,473
Loans current	18,488	18,258
Total Loans Receivable	19,034	19,731
Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	13,667	6,135
Financing Receivables, 30 to 59 Days Past Due | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	1,722	95
Financing Receivables, 30 to 59 Days Past Due | Commercial and Industrial Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	5,523	1,434
Financing Receivables, 30 to 59 Days Past Due | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	11	57
Financing Receivables, 30 to 59 Days Past Due | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	363	217
Financing Receivables, 30 to 59 Days Past Due | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	2,778	74
Financing Receivables, 30 to 59 Days Past Due | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	2,968	3,854
Financing Receivables, 30 to 59 Days Past Due | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	244	325
Financing Receivables, 30 to 59 Days Past Due | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	58	79
Financing Receivables, 30 to 59 Days Past Due | Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due		164
Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	848	3,117
Financing Receivables, 60 to 89 Days Past Due | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	175	118
Financing Receivables, 60 to 89 Days Past Due | Commercial and Industrial Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	136	1,336
Financing Receivables, 60 to 89 Days Past Due | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due		97
Financing Receivables, 60 to 89 Days Past Due | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due		25
Financing Receivables, 60 to 89 Days Past Due | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	48
Financing Receivables, 60 to 89 Days Past Due | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	444	756
Financing Receivables, 60 to 89 Days Past Due | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	30	770
Financing Receivables, 60 to 89 Days Past Due | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	15	15
Financing Receivables, 60 to 89 Days Past Due | Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	206	756
Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	4,547	5,370
Financing Receivables, Equal to Greater than 90 Days Past Due | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	138	168
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial and Industrial Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	1,599	1,576
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
Loans past due	177	82
Financing Receivables, Equal to Greater than 90 Days Past Due | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due		373
Financing Receivables, Equal to Greater than 90 Days Past Due | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	1,081	1,852
Financing Receivables, Equal to Greater than 90 Days Past Due | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	1,177	1,019
Financing Receivables, Equal to Greater than 90 Days Past Due | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	356	271
Financing Receivables, Equal to Greater than 90 Days Past Due | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	19	29
Financing Receivables, Equal to Greater than 90 Days Past Due | Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due
Loans past due	340	553
Agricultural Portfolio Segment | Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	111,975	105,512
Commercial Portfolio Segment | Commercial and Industrial Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	513,778	503,624
Commercial Real Estate Portfolio Segment
Financing Receivable, Recorded Investment, Past Due
Loans past due	4,458	2,777
Loans current	1,193,988	1,169,194
Total Loans Receivable	1,198,446	1,171,971
Commercial Real Estate Portfolio Segment | Commercial Real Estate Construction and Development Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	194,712	165,276
Commercial Real Estate Portfolio Segment | Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	87,030	87,868
Commercial Real Estate Portfolio Segment | Multifamily Real Estate Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	126,802	134,506
Commercial Real Estate Portfolio Segment | Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	789,902	784,321
Commercial Real Estate Portfolio Segment | Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	3,152	348
Commercial Real Estate Portfolio Segment | Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	48	122
Commercial Real Estate Portfolio Segment | Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	1,258	2,307
Residential Portfolio Segment
Financing Receivable, Recorded Investment, Past Due
Loans past due	5,219	6,995
Loans current	460,710	462,435
Total Loans Receivable	465,929	469,430
Residential Portfolio Segment | Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	349,742	352,226
Residential Portfolio Segment | Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	116,187	117,204
Residential Portfolio Segment | Financing Receivables, 30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	3,212	4,179
Residential Portfolio Segment | Financing Receivables, 60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	474	1,526
Residential Portfolio Segment | Financing Receivables, Equal to Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Loans past due	1,533	1,290
Consumer Portfolio Segment | Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Total Loans Receivable	$ 36,030	$ 36,158

Loans Receivable and the Allo51

Loans Receivable and the Allowance for Loan Losses Nonaccrual and 90+ Days Past Due and Still Accruing Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due
Document Period End Date	Mar. 31, 2018
Loans in nonaccrual status	$ 13,566	$ 14,784
Loans 90 days past due and still accruing	116	207
Agricultural Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	390	168
Commercial and Industrial Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	7,125	7,124
Commercial Real Estate Construction and Development Loan Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	186	188
Farmland Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	140	386
Commercial Real Estate Loan Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	3,924	5,279
Residential Real Estate First Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	1,312	1,228
Loans 90 days past due and still accruing	103	205
Residential Real Estate Junior Lien Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	434	346
Loans 90 days past due and still accruing	13	2
Purchased Credit Impaired Loans Receivable
Financing Receivable, Recorded Investment, Past Due
Loans, nonaccrual or 90 days past due and still accruing	500	700
Loans, discount, nonaccrual or 90 days past due and still accruing	0	100
Consumer Loan Financing Receivable
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	55	65
Commercial Real Estate Portfolio Segment
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	4,250	5,853
Loans 90 days past due and still accruing		0
Residential Portfolio Segment
Financing Receivable, Recorded Investment, Past Due
Loans in nonaccrual status	1,746	1,574
Loans 90 days past due and still accruing	$ 116	$ 207

Loans Receivable and the Allo52

Loans Receivable and the Allowance for Loan Losses Accretable Yield for Loans Acquired and Accounted for Under ASC 310-30 (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Loans and Leases Receivable Disclosure [Abstract]
Balance at beginning of period	$ 840	$ 1,961
Accretion	(277)	(416)
Reclassifications (to) from nonaccretable difference	45	88
Balance at end of period	$ 608	$ 1,633

Loans Receivable and the Allo53

Loans Receivable and the Allowance for Loan Losses Textual References (Details) $ in Millions	Mar. 31, 2018USD ($)quarters	Dec. 31, 2017USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans pledged for Federal Home Loan Bank debt	$ 487.7	$ 477.6
Allowance for loan losses, maximum overage percentage	20.00%
Allowance for loan losses, 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	$ 20.5
Purchased credit-impaired loans, discount	$ 1.5

Derivative and Hedging Activi54

Derivative and Hedging Activities Derivative Instruments (Details) - Fair Value Hedging $ in Thousands	Mar. 31, 2018USD ($)count
Interest Rate Swap
Derivative [Line Items]
Number of instruments held | count	1
Notional amount	$ 4,354
Hedged Item, Loans [Member]
Derivative [Line Items]
Carrying amount of the hedged asset	4,516
Adjustment included in the carrying amount of the hedged asset	$ 161

Derivative and Hedging Activi55

Derivative and Hedging Activities Fair Values of Outstanding Derivative Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Other Liabilities [Member] | Interest Rate Swap | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Fair value of interest rate derivative liabilities	$ 161	$ 0

Derivative and Hedging Activi56

Derivative and Hedging Activities Effect of Derivative Instruments on Income (Details) - Interest Rate Swap - Designated as Hedging Instrument - Fair Value Hedging - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	$ (1)	$ 0
Loss on derivative	(162)	0
Interest Income
Derivative Instruments, Gain (Loss) [Line Items]
Gain on derivative	161	0
Other gain (loss)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivative, net	0	0
Loss on derivative	0	0
Gain on derivative	$ 0	$ 0

Derivative and Hedging Activi57

Derivative and Hedging Activities Offsetting of Financial Assets and Financial Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gross amounts of recognized liabilities	$ (161)	$ 0
Gross amounts offset in the balance sheet	0	0
Net amounts of liabilities presented in balance sheet	(161)	0
Financial instruments	0	0
Cash collateral pledged	(130)	0
Net liabilities	$ (31)	$ 0

Goodwill and Intangible Asset58

Goodwill and Intangible Assets Changes in Carrying Amount of Non-Goodwill Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018
Schedule of Intangible Assets [Line Items]
Balance, beginning of period	$ 12,046
Amortization expense	(657)	$ (849)
Balance at end of period	11,389
Gross carrying amount			$ 28,276
Accumulated amortizations			(16,887)
Net book value	12,046		11,389
Trade names intangible
Schedule of Intangible Assets [Line Items]
Balance, beginning of period	7,040
Amortization expense	0
Balance at end of period	7,040
Gross carrying amount			7,040
Net book value	7,040		7,040
Insurance agency intangible
Schedule of Intangible Assets [Line Items]
Balance, beginning of period	148
Amortization expense	(9)
Balance at end of period	139
Gross carrying amount			1,320
Accumulated amortizations			(1,181)
Net book value	148		139
Core deposit intangible
Schedule of Intangible Assets [Line Items]
Balance, beginning of period	4,011
Amortization expense	(594)
Balance at end of period	3,417
Gross carrying amount			18,206
Accumulated amortizations			(14,789)
Net book value	4,011		3,417
Trade names intangible
Schedule of Intangible Assets [Line Items]
Balance, beginning of period	744
Amortization expense	(50)
Balance at end of period	694
Gross carrying amount			1,380
Accumulated amortizations			(686)
Net book value	744		694
Customer list intangible
Schedule of Intangible Assets [Line Items]
Balance, beginning of period	103
Amortization expense	(4)
Balance at end of period	99
Gross carrying amount			330
Accumulated amortizations			(231)
Net book value	$ 103		$ 99

Goodwill and Intangible Asset59

Goodwill and Intangible Assets Textual References (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Schedule of Intangible Assets [Line Items]
Goodwill, impairment loss	$ 0
Goodwill	64,654	$ 64,654
Trade names intangible
Schedule of Intangible Assets [Line Items]
Impairment of indefinite-lived trade name intangible	$ 0

Other Assets (Details)

Other Assets (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Other Assets [Abstract]
Federal Home Loan Bank stock	$ 12,780,000	$ 11,324,000
Prepaid expense	2,067,000	2,992,000
Mortgage Servicing Rights	2,536,000	2,316,000
Federal & state income taxes receivable, current	897,000	3,120,000
Accounts receivable & other miscellaneous assets	4,479,000	3,009,000
Other assets	22,759,000	22,761,000
Investment in Federal Home Loan Bank Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other than Temporary Impairment Losses, Investments	$ 0	$ 0

Short-Term Borrowings (Details)

Short-Term Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Short-term Debt [Line Items]
Weighted Average Cost	1.06%	0.73%
Short-term debt	$ 93,311	$ 97,229
Available-for-sale securities pledged as collateral	238,200	237,400
Federal Reserve Bank advances
Short-term Debt [Line Items]
Short-term debt	0	0
Unsercured line of credit, maximum borrowing capacity	11,500	11,536
Available-for-sale securities pledged as collateral	$ 12,700	$ 12,800
Federal funds purchased
Short-term Debt [Line Items]
Weighted Average Cost	1.95%	1.77%
Short-term debt	$ 25,573	$ 1,000
Securities sold under agreements to repurchase
Short-term Debt [Line Items]
Weighted Average Cost	0.72%	0.71%
Short-term debt	$ 67,738	$ 96,229
Line of credit
Short-term Debt [Line Items]
Short-term debt	0
Unsercured line of credit, maximum borrowing capacity	$ 5,000
Debt Instrument, Issuance Date	Apr. 30, 2015
Debt instrument, maturity date	Apr. 28, 2018
London Interbank Offered Rate (LIBOR) | Line of credit
Short-term Debt [Line Items]
Description of variable interest rate basis	one-month LIBOR
Debt instrument, basis spread on variable rate	2.00%

Subordinated Notes Payable (Det

Subordinated Notes Payable (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
		Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Junior subordinated notes issued to capital trusts, book value		$ 23,817	$ 23,793
Junior subordinated notes
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary trust, face value	[1]	24,743	24,743
Junior subordinated notes issued to capital trusts, book value		23,817	23,793
Junior subordinated notes | CBI Capital Trust II
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary trust, face value	[1],[2]	7,217	7,217
Junior subordinated notes issued to capital trusts, book value	[1],[2]	$ 6,688	$ 6,674
Interest rate	[1],[2]	5.62%	5.09%
Debt instrument, maturity date	[1],[2]	Mar. 15, 2038	Mar. 15, 2038
Debt instrument, earliest call date	[1],[2]	Mar. 15, 2013	Mar. 15, 2013
Junior subordinated notes | CBI Capital Trust II | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Description of variable interest rate basis	[1],[2]	Three-month LIBOR
Debt instrument, basis spread on variable rate	[1],[2]	3.50%
Junior subordinated notes | Barron Investment Capital Trust I
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary trust, face value	[1],[2]	$ 2,062	$ 2,062
Junior subordinated notes issued to capital trusts, book value	[1],[2]	$ 1,665	$ 1,655
Interest rate	[1],[2]	4.42%	3.82%
Debt instrument, maturity date	[1],[2]	Sep. 23, 2036	Sep. 23, 2036
Debt instrument, earliest call date	[1],[2]	Sep. 23, 2011	Sep. 23, 2011
Junior subordinated notes | Barron Investment Capital Trust I | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Description of variable interest rate basis	[1],[2]	Three-month LIBOR
Debt instrument, basis spread on variable rate	[1],[2]	2.15%
Junior subordinated notes | MidWestOne Statutory Trust II
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary trust, face value	[1]	$ 15,464	$ 15,464
Junior subordinated notes issued to capital trusts, book value	[1]	$ 15,464	$ 15,464
Interest rate	[1]	3.71%	3.18%
Debt instrument, maturity date	[1]	Dec. 15, 2037	Dec. 15, 2037
Debt instrument, earliest call date	[1]	Dec. 15, 2012	Dec. 15, 2012
Junior subordinated notes | MidWestOne Statutory Trust II | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Description of variable interest rate basis	[1]	Three-month LIBOR
Debt instrument, basis spread on variable rate	[1]	1.59%
Maximum
Debt Instrument [Line Items]
Junior subordinated debenture owed to unconsolidated subsidiary, deferral period		5 years
[1]	(1) All distributions are cumulative and paid in cash quarterly.
[2]	(2) Central Bancshares Capital Trust II and Barron Investment Capital Trust I were established by Central prior to the Company’s merger with Central, and the junior subordinated notes issued by Central were assumed by the Company.

Long-Term Borrowings (Details)

Long-Term Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2015	Apr. 30, 2015
Debt Instrument [Line Items]
Long-term debt, excluding subordinated debt, weighted average interest rate	2.05%	1.88%
Long-term Debt, Gross	$ 134,250	$ 127,500
Federal Home Loan Bank Borrowings
Debt Instrument [Line Items]
Weighted average cost	1.93%	1.72%
Long-term Debt, Gross	$ 123,000	$ 115,000
Federal Home Loan, Bank advances general debt obligations, disclosures maximum borrowing capacity as percentage of total assets	35.00%
Note payable to unaffiliated bank
Debt Instrument [Line Items]
Weighted average cost	3.41%	3.32%
Long-term Debt, Gross	$ 11,250	$ 12,500
Debt Instrument, Issuance Date		Apr. 30, 2015
Original note face amount				$ 35,000
Debt instrument, maturity date		Jun. 30, 2020
Long-term debt, amount advanced			$ 25,000
Debt instrument, frequency of periodic payment	quarterly
Debt Instrument, Date of First Required Payment		Sep. 30, 2015

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Expected provision, amount	$ 2,053	$ 3,235
Tax-exempt interest, amount	(490)	(786)
Bank-owned life insurance, amount	(91)	(115)
State income taxes, net of federal income tax benefit, amount	529	405
General business credits, amount	(47)	(21)
Other, amount	30	(189)
Total income tax provision, amount	$ 1,984	$ 2,529
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Expected provision, percent	21.00%	35.00%
Tax-exempt interest, percent	(5.00%)	(8.50%)
Bank-owned life insurance, percent	(0.90%)	(1.20%)
State income taxes, net of federal income tax benefit, percent	5.40%	4.40%
General business credits, percent	(0.80%)	(0.20%)
Other, percent	0.60%	(2.10%)
Total income tax provision, percent	20.30%	27.40%

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share [Abstract]
Net income	$ 7,793	$ 6,713
Earnings per common share - basic	$ 0.64	$ 0.58
Earnings per common share - diluted	$ 0.64	$ 0.58

Estimated Fair Value of Finan66

Estimated Fair Value of Financial Instruments and Fair Value Measurements Fair Value Financial Assets and Liabilities Measured on a Recurring Basis (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018USD ($)count	Dec. 31, 2017USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	$ 446,087	$ 447,660
Derivative liability	161	0
Transfer of assets, fair value, to (from) Level 3, amount	0	0
Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative liability	0
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative liability	161
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative liability	0
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		447,660
Derivative liability	161
Recurring | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		2,336
Derivative liability	0
Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		445,324
Derivative liability	161
Recurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative liability	0
U.S. Government agencies and corporations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	15,399	15,626
U.S. Government agencies and corporations | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	15,399	15,626
U.S. Government agencies and corporations | Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	15,399	15,626
State and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	147,526	141,839
State and political subdivisions | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	147,526	141,839
State and political subdivisions | Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	147,526	141,839
Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	47,260	48,497
Mortgage-backed securities | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	47,260	48,497
Mortgage-backed securities | Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	47,260	48,497
Collateralized mortgage obligations | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	170,805	168,196
Collateralized mortgage obligations | Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	170,805	168,196
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	65,097	71,166
Corporate debt securities | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	65,097	71,166
Corporate debt securities | Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	$ 65,097	71,166
Debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Sample size used to validate pricing service results | count	30
Available for sale securities		445,324
Debt securities | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	$ 446,087	445,324
Debt securities | Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	$ 446,087	445,324
Other equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		2,336
Other equity securities | Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		2,336
Other equity securities | Recurring | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		$ 2,336

Estimated Fair Value of Finan67

Estimated Fair Value of Financial Instruments and Fair Value Measurements Fair Value Assets and Liabilities Measured on a Nonrecurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Other real estate owned	$ 1,001	$ 2,010
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Collateral dependent impaired loans	8,877	3,927
Other real estate owned	1,001	2,010
Nonrecurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Collateral dependent impaired loans	8,877	3,927
Other real estate owned	$ 1,001	$ 2,010

Estimated Fair Value of Finan68

Estimated Fair Value of Financial Instruments and Fair Value Measurements Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Investment securities:
Equity securities	$ 2,815
Equity securities		$ 2,336
Available for sale debt securities	446,087	445,324
Held to maturity securities	194,617	195,619
Held to maturity, estimated fair value	190,593	194,343
Accrued interest receivable	13,337	14,732
Federal Home Loan Bank stock	12,780	11,324
Deposits:
Non-interest-bearing demand	450,168	461,969
Interest-bearing checking	1,240,208	1,228,112
Savings	215,940	213,430
Derivative liability	161	0
Accrued interest payable	1,459	1,428
Reported Value Measurement
Financial Assets
Cash and cash equivalents	42,396	50,972
Investment securities:
Equity securities	2,815
Equity securities		2,336
Available for sale debt securities	446,087	445,324
Held to maturity securities	194,617	195,619
Total investment securities	643,519	643,279
Loans held for sale	870	856
Loans, net	2,296,487	2,258,636
Accrued interest receivable	13,337	14,732
Deposits:
Non-interest-bearing demand	450,168	461,969
Interest-bearing checking	1,240,208	1,228,112
Savings	215,940	213,430
Certificates of deposit under $100,000	332,727	324,681
Certificates of deposit $100,000 and over	392,878	377,127
Total deposits	2,631,921	2,605,319
Federal funds purchased and securities sold under agreements to repurchase	93,311	97,229
Federal Home Loan Bank borrowings	123,000	115,000
Junior subordinated notes issued to capital trusts	23,817	23,793
Long-term debt	11,250	12,500
Derivative liability	161
Estimate of Fair Value Measurement
Financial Assets
Cash and cash equivalents	42,396	50,972
Investment securities:
Equity securities	2,815
Equity securities		2,336
Available for sale debt securities	446,087	445,324
Held to maturity, estimated fair value	190,593	194,343
Total investment securities	639,495	642,003
Loans held for sale	895	871
Loans, net	2,247,398	2,256,726
Accrued interest receivable	13,337	14,732
Federal Home Loan Bank stock	12,780	11,324
Deposits:
Non-interest-bearing demand	450,168	461,969
Interest-bearing checking	1,240,208	1,228,112
Savings	215,940	213,430
Certificates of deposit under $100,000	328,009	321,197
Certificates of deposit $100,000 and over	389,430	374,685
Total deposits	2,623,755	2,599,393
Federal funds purchased and securities sold under agreements to repurchase	93,311	97,229
Federal Home Loan Bank borrowings	120,850	114,945
Junior subordinated notes issued to capital trusts	21,032	19,702
Long-term debt	11,250	12,500
Derivative liability	161
Fair Value, Inputs, Level 1
Financial Assets
Cash and cash equivalents	42,396	50,972
Investment securities:
Equity securities	2,815
Equity securities		2,336
Total investment securities	2,815	2,336
Accrued interest receivable	13,337	14,732
Deposits:
Non-interest-bearing demand	450,168	461,969
Interest-bearing checking	1,240,208	1,228,112
Savings	215,940	213,430
Total deposits	1,906,316	1,903,511
Federal funds purchased and securities sold under agreements to repurchase	93,311	97,229
Derivative liability	0
Fair Value, Inputs, Level 2
Investment securities:
Equity securities	0
Equity securities		0
Available for sale debt securities	446,087	445,324
Held to maturity, estimated fair value	190,593	194,343
Total investment securities	636,680	639,667
Loans held for sale	895
Loans, net		2,256,726
Federal Home Loan Bank stock	12,780	11,324
Deposits:
Certificates of deposit under $100,000	328,009	321,197
Certificates of deposit $100,000 and over	389,430	374,685
Total deposits	717,439	695,882
Federal Home Loan Bank borrowings	120,850	114,945
Junior subordinated notes issued to capital trusts	21,032	19,702
Long-term debt	11,250	12,500
Derivative liability	161
Fair Value, Inputs, Level 3
Investment securities:
Equity securities	0
Equity securities		0
Loans held for sale		871
Loans, net	2,247,398
Deposits:
Derivative liability	$ 0

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event - Common Stock	Apr. 19, 2018$ / shares
Subsequent Event
Dividends payable, amount per share	$ 0.195
Dividends payable, date to be paid	Jun. 15, 2018
Dividends payable, date of record	Jun. 1, 2018