Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	General The accompanying unaudited consolidated financial statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information or footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments, consisting of normal and recurring items, necessary for a fair presentation of the consolidated financial statements have been made. These interim financial statements should be read in conjunction with the audited consolidated financial statements and footnote disclosures for the Company previously filed with the SEC in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016. Operating results for the period ended June 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017. When we refer to the “Company,” “we,” “our,” or “us” in this Report, we mean IBERIABANK Corporation and subsidiaries (consolidated). When we refer to the “Parent,” we mean IBERIABANK Corporation. See the Glossary of Acronyms at the end of this Report for terms used throughout this Report. Principles of Consolidation The Company’s consolidated financial statements include all entities in which the Company has a controlling financial interest under either the voting interest or variable interest model. The assessment of whether or not the Company has a controlling interest (i.e., the primary beneficiary) in a variable interest entity ("VIE") is performed on an on-going basis. All equity investments in non-consolidated VIEs are included in "other assets" in the Company’s consolidated balance sheets. The Company’s maximum exposure to loss as a result of its involvement with non-consolidated VIEs was approximately $94 million and $91 million at June 30, 2017 and December 31, 2016, respectively. The Company's maximum exposure to loss was equivalent to the carrying value of its investments and any related outstanding loans to the non-consolidated VIEs. Investments in entities that are not consolidated are accounted for under either the equity, cost, or proportional amortization method of accounting. Investments for which the Company has the ability to exercise significant influence over the operating and financing decisions of the entity are accounted for under the equity method. Investments for which the Company does not hold such ability are accounted for under the cost method. Investments in qualified affordable housing projects, which meet certain criteria, are accounted for under the proportional amortization method. The consolidated financial statements include the accounts of the Company and its subsidiaries, IBERIABANK; Lenders Title Company; IBERIA Capital Partners, LLC; 1887 Leasing, LLC; IBERIA Asset Management, Inc.; 840 Denning, LLC; and IBERIA CDE, LLC. Effective January 1, 2017, IBERIABANK Mortgage Company, previously a subsidiary of IBERIABANK, merged into IBERIABANK. All significant intercompany balances and transactions have been eliminated in consolidation. Nature of Operations The Company offers commercial and retail banking products and services to customers throughout locations in eight states through IBERIABANK. The Company also operates mortgage production offices in 10 states and offers a full line of title insurance and closing services throughout Arkansas and Louisiana through LTC and its subsidiaries. ICP provides equity research, institutional sales and trading, and corporate finance services throughout the energy industry. 1887 Leasing, LLC owns an aircraft used by management of the Company. IAM provides wealth management and trust services for commercial and private banking clients. 840 Denning, LLC invests in a commercial rental property. CDE is engaged in the purchase of tax credits. Reclassifications Certain amounts reported in prior periods have been reclassified to conform to the current period presentation. These reclassifications did not have a material effect on previously reported consolidated financial statements. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Material estimates that are susceptible to significant change in the near term are the allowance for credit losses, valuation of and accounting for acquired loans, goodwill and other intangibles, and income taxes. Concentrations of Credit Risk Most of the Company’s business activity is with customers located in the southeastern United States. The Company’s lending activity is concentrated in its market areas in those states. The Company has emphasized originations of commercial loans and private banking loans, defined as loans to higher net worth clients. Repayments on loans are expected to come from cash flows of the borrower and/or guarantor. Losses on secured loans are limited by the net realizable value of the collateral upon default of the borrowers and guarantor support. Concentrations in commercial real estate have increased as a result of the Company's organic growth and recent acquisitions of banks with significant CRE portfolios. Additionally, as the Company has executed its risk-off strategy over the past two years, CRE concentrations have naturally increased as a percentage of the total portfolio. The Company believes it does not have any excessive concentrations to any one industry or customer.

General

The accompanying unaudited consolidated financial statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information or footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments, consisting of normal and recurring items, necessary for a fair presentation of the consolidated financial statements have been made. These interim financial statements should be read in conjunction with the audited consolidated financial statements and footnote disclosures for the Company previously filed with the SEC in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016. Operating results for the period ended June 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017.

When we refer to the “Company,” “we,” “our,” or “us” in this Report, we mean IBERIABANK Corporation and subsidiaries (consolidated). When we refer to the “Parent,” we mean IBERIABANK Corporation. See the Glossary of Acronyms at the end of this Report for terms used throughout this Report.

Principles of Consolidation

The Company’s consolidated financial statements include all entities in which the Company has a controlling financial interest under either the voting interest or variable interest model. The assessment of whether or not the Company has a controlling interest (i.e., the primary beneficiary) in a variable interest entity ("VIE") is performed on an on-going basis. All equity investments in non-consolidated VIEs are included in "other assets" in the Company’s consolidated balance sheets. The Company’s maximum exposure to loss as a result of its involvement with non-consolidated VIEs was approximately $94 million and $91 million at June 30, 2017 and December 31, 2016, respectively. The Company's maximum exposure to loss was equivalent to the carrying value of its investments and any related outstanding loans to the non-consolidated VIEs.

Investments in entities that are not consolidated are accounted for under either the equity, cost, or proportional amortization method of accounting. Investments for which the Company has the ability to exercise significant influence over the operating and financing decisions of the entity are accounted for under the equity method. Investments for which the Company does not hold such ability are accounted for under the cost method. Investments in qualified affordable housing projects, which meet certain criteria, are accounted for under the proportional amortization method.

The consolidated financial statements include the accounts of the Company and its subsidiaries, IBERIABANK; Lenders Title Company; IBERIA Capital Partners, LLC; 1887 Leasing, LLC; IBERIA Asset Management, Inc.; 840 Denning, LLC; and IBERIA CDE, LLC. Effective January 1, 2017, IBERIABANK Mortgage Company, previously a subsidiary of IBERIABANK, merged into IBERIABANK. All significant intercompany balances and transactions have been eliminated in consolidation.

Nature of Operations

The Company offers commercial and retail banking products and services to customers throughout locations in eight states through IBERIABANK. The Company also operates mortgage production offices in 10 states and offers a full line of title insurance and closing services throughout Arkansas and Louisiana through LTC and its subsidiaries. ICP provides equity research, institutional sales and trading, and corporate finance services throughout the energy industry. 1887 Leasing, LLC owns an aircraft used by management of the Company. IAM provides wealth management and trust services for commercial and private banking clients. 840 Denning, LLC invests in a commercial rental property. CDE is engaged in the purchase of tax credits.

Reclassifications

Certain amounts reported in prior periods have been reclassified to conform to the current period presentation. These reclassifications did not have a material effect on previously reported consolidated financial statements.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Material estimates that are susceptible to significant change in the near term are the allowance for credit losses, valuation of and accounting for acquired loans, goodwill and other intangibles, and income taxes.

Concentrations of Credit Risk

Most of the Company’s business activity is with customers located in the southeastern United States. The Company’s lending activity is concentrated in its market areas in those states. The Company has emphasized originations of commercial loans and private banking loans, defined as loans to higher net worth clients. Repayments on loans are expected to come from cash flows of the borrower and/or guarantor. Losses on secured loans are limited by the net realizable value of the collateral upon default of the borrowers and guarantor support. Concentrations in commercial real estate have increased as a result of the Company's organic growth and recent acquisitions of banks with significant CRE portfolios. Additionally, as the Company has executed its risk-off strategy over the past two years, CRE concentrations have naturally increased as a percentage of the total portfolio. The Company believes it does not have any excessive concentrations to any one industry or customer.