Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Notes)	9 Months Ended
Sep. 30, 2014
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation: The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America for interim financial reporting and with instructions for Form 10-Q and Regulation S-X. These financial statements include all adjustments (consisting of normal recurring accruals) which in the opinion of management are considered necessary for the fair presentation of the financial position and results of operations for the periods shown. Certain prior year amounts have been reclassified to conform to the current year presentation. The Company considers that it operates as one business segment, a commercial bank. Operating results for the nine month period ended September 30, 2014 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2014. For further information, refer to the consolidated financial statements and footnotes thereto included in the Form 10-K Annual Report of Hills Bancorporation and subsidiary (the “Company”) for the year ended December 31, 2013 filed with the Securities Exchange Commission on March 11, 2014. The consolidated balance sheet as of December 31, 2013, has been derived from the audited consolidated financial statements for that period. The Company evaluated subsequent events through the filing date of its quarterly report on Form 10-Q with the SEC. Effect of New Financial Accounting Standards: In January 2014, the FASB issued ASU No. 2014-01, Accounting for Investments in Qualified Affordable Housing Projects", to amend FASB ASC Topic 323, Investments – Equity Method and Joint Ventures. The objective of this standard is to provide guidance on accounting for investments by a reporting entity in flow-through limited liability entities that manage or invest in affordable housing projects that qualify for the low-income housing tax credit. The amendments in the standard permit, but do not require, reporting entities to make an accounting policy election to account for their investments in qualified affordable housing projects using the proportional amortization method if certain conditions are met. Under the proportional amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense (benefit). The standard will be effective for the Company beginning January 1, 2015; however, early adoption is permitted. The Company does have significant investments in such qualified affordable housing projects and is currently reviewing the provisions of this standard to determine what, if any, impacts it may have on the Company’s financial position or results of operations. In January 2014, the FASB issued ASU No. 2014-04, Receivables – Troubled Debt Restructurings by Creditors (Subtopic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. ASU 2014-4 clarifies that an in substance foreclosure repossession or foreclosure occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either the creditor obtaining legal title to the residential real estate property upon foreclosure or the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar legal agreement. Additional disclosures are required. ASU 2014-4 is effective for annual periods and interim periods within those annual periods beginning after December 15, 2014. The adoption of ASU 2014-4 by the Company is not expected to have a material impact. In May 2014, The FASB and International Accounting Standards Board (IASB) issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). The core principle of ASU 2014-09 is that a company should recognize revenue to depict the transfer of promised good or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. For financial institutions, significant changes are not expected given that most financial instruments are not in the scope of the accounting standard update. ASU 2014-09 is effective for annual periods and interim periods within those annual periods beginning after December 15, 2016. Early adoption is not permitted. The Company is currently reviewing the provisions of this standard to determine the application to financial institutions. The adoption of ASU 2014-09 by the Company is not expected to have a material impact.

Summary of Significant Accounting Policies

Basis of Presentation:

The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America for interim financial reporting and with instructions for Form 10-Q and Regulation S-X. These financial statements include all adjustments (consisting of normal recurring accruals) which in the opinion of management are considered necessary for the fair presentation of the financial position and results of operations for the periods shown. Certain prior year amounts have been reclassified to conform to the current year presentation. The Company considers that it operates as one business segment, a commercial bank.

Operating results for the nine month period ended September 30, 2014 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2014. For further information, refer to the consolidated financial statements and footnotes thereto included in the Form 10-K Annual Report of Hills Bancorporation and subsidiary (the “Company”) for the year ended December 31, 2013 filed with the Securities Exchange Commission on March 11, 2014. The consolidated balance sheet as of December 31, 2013, has been derived from the audited consolidated financial statements for that period.

The Company evaluated subsequent events through the filing date of its quarterly report on Form 10-Q with the SEC.

Effect of New Financial Accounting Standards:

In January 2014, the FASB issued ASU No. 2014-01, Accounting for Investments in Qualified Affordable Housing Projects", to amend FASB ASC Topic 323, Investments – Equity Method and Joint Ventures. The objective of this standard is to provide guidance on accounting for investments by a reporting entity in flow-through limited liability entities that manage or invest in affordable housing projects that qualify for the low-income housing tax credit. The amendments in the standard permit, but do not require, reporting entities to make an accounting policy election to account for their investments in qualified affordable housing projects using the proportional amortization method if certain conditions are met. Under the proportional amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense (benefit). The standard will be effective for the Company beginning January 1, 2015; however, early adoption is permitted. The Company does have significant investments in such qualified affordable housing projects and is currently reviewing the provisions of this standard to determine what, if any, impacts it may have on the Company’s financial position or results of operations.

In January 2014, the FASB issued ASU No. 2014-04, Receivables – Troubled Debt Restructurings by Creditors (Subtopic 310-40): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. ASU 2014-4 clarifies that an in substance foreclosure repossession or foreclosure occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either the creditor obtaining legal title to the residential real estate property upon foreclosure or the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar legal agreement. Additional disclosures are required. ASU 2014-4 is effective for annual periods and interim periods within those annual periods beginning after December 15, 2014. The adoption of ASU 2014-4 by the Company is not expected to have a material impact.

In May 2014, The FASB and International Accounting Standards Board (IASB) issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). The core principle of ASU 2014-09 is that a company should recognize revenue to depict the transfer of promised good or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. For financial institutions, significant changes are not expected given that most financial instruments are not in the scope of the accounting standard update. ASU 2014-09 is effective for annual periods and interim periods within those annual periods beginning after December 15, 2016. Early adoption is not permitted. The Company is currently reviewing the provisions of this standard to determine the application to financial institutions. The adoption of ASU 2014-09 by the Company is not expected to have a material impact.