Basis Of Presentation (Policy)	3 Months Ended
Mar. 31, 2012
Basis Of Presentation [Abstract]
Principles Of Consolidation	PRINCIPLES OF CONSOLIDATION The unaudited consolidated financial statements include the accounts of IBERIABANK Corporation (the "Company") and its wholly owned subsidiaries, IBERIABANK, Lenders Title Company ("LTC"), IBERIA Capital Partners LLC ("ICP"), IB Aircraft Holdings, LLC, IBERIA Asset Management Inc. ("IAM"), and IBERIA CDE, LLC ("CDE"). All significant intercompany balances and transactions have been eliminated in consolidation. All normal, recurring adjustments which, in the opinion of management are necessary for a fair presentation of the financial statements, have been included. Certain amounts reported in prior periods have been reclassified to conform to the current period presentation.
Nature Of Operations	NATURE OF OPERATIONS The Company offers commercial and retail banking products and services to customers throughout locations in six states through IBERIABANK. The Company also operates mortgage production offices in twelve states through IBERIABANK Mortgage Company ("IMC"), 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. IB Aircraft Holdings, LLC owns a fractional share of an aircraft used by management of the Company and its subsidiaries. IAM provides wealth management and trust services for commercial and private banking clients. CDE is utilized to purchase tax credits.
Use Of Estimates	USE OF ESTIMATES The preparation of financial statements in conformity with generally accepted accounting principles 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 loan losses, valuation of and accounting for loans covered by loss sharing arrangements with the FDIC and the related loss share receivable, valuation of goodwill, intangible assets and other purchase accounting adjustments, and share-based compensation.
Concentration Of Credit Risks	CONCENTRATION OF CREDIT RISKS Most of the Company's business activity is with customers located within the States of Louisiana, Florida, Arkansas, Alabama, Texas, and Tennessee. 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 larger consumer clients. Repayment of loans is expected to come from cash flows of the borrower. Losses on secured loans are limited by the value of the collateral upon default of the borrowers. The Company does not have any significant concentrations to any one industry or customer.
Segments	SEGMENTS Upon the merger of the Company's two financial institution subsidiaries, IBERIABANK and IBERIABANK fsb, at the close of business on December 31, 2010, all of the Company's banking operations are considered by management to be aggregated in one reportable operating segment. Because the overall banking operations comprise substantially all of the consolidated operations and none of the Company's other subsidiaries, either individually or in the aggregate, meet quantitative materiality thresholds provided by ASC Topic 280, no separate segment disclosures are presented in these consolidated financial statements.

Basis Of Presentation (Policy)

3 Months Ended

Mar. 31, 2012

PRINCIPLES OF CONSOLIDATION

The unaudited consolidated financial statements include the accounts of IBERIABANK Corporation (the "Company") and its wholly owned subsidiaries, IBERIABANK, Lenders Title Company ("LTC"), IBERIA Capital Partners LLC ("ICP"), IB Aircraft Holdings, LLC, IBERIA Asset Management Inc. ("IAM"), and IBERIA CDE, LLC ("CDE"). All significant intercompany balances and transactions have been eliminated in consolidation. All normal, recurring adjustments which, in the opinion of management are necessary for a fair presentation of the financial statements, have been included. Certain amounts reported in prior periods have been reclassified to conform to the current period presentation.

Nature Of Operations

NATURE OF OPERATIONS

The Company offers commercial and retail banking products and services to customers throughout locations in six states through IBERIABANK. The Company also operates mortgage production offices in twelve states through IBERIABANK Mortgage Company ("IMC"), 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. IB Aircraft Holdings, LLC owns a fractional share of an aircraft used by management of the Company and its subsidiaries. IAM provides wealth management and trust services for commercial and private banking clients. CDE is utilized to purchase tax credits.

Use Of Estimates

USE OF ESTIMATES

The preparation of financial statements in conformity with generally accepted accounting principles 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 loan losses, valuation of and accounting for loans covered by loss sharing arrangements with the FDIC and the related loss share receivable, valuation of goodwill, intangible assets and other purchase accounting adjustments, and share-based compensation.

Concentration Of Credit Risks

CONCENTRATION OF CREDIT RISKS

Most of the Company's business activity is with customers located within the States of Louisiana, Florida, Arkansas, Alabama, Texas, and Tennessee. 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 larger consumer clients. Repayment of loans is expected to come from cash flows of the borrower. Losses on secured loans are limited by the value of the collateral upon default of the borrowers. The Company does not have any significant concentrations to any one industry or customer.

Segments

SEGMENTS

Upon the merger of the Company's two financial institution subsidiaries, IBERIABANK and IBERIABANK fsb, at the close of business on December 31, 2010, all of the Company's banking operations are considered by management to be aggregated in one reportable operating segment. Because the overall banking operations comprise substantially all of the consolidated operations and none of the Company's other subsidiaries, either individually or in the aggregate, meet quantitative materiality thresholds provided by ASC Topic 280, no separate segment disclosures are presented in these consolidated financial statements.

- Definition

Description of risks that arise due to concentrations of operating facilities, revenues, assets, customers, vendors or the like in a certain geographic area, either domestic or foreign. The description may address risks inherent in the geographic area, and, at a minimum, informs users of the general nature of the risk, but excludes "Information about Geographic Areas" that may be disclosed elsewhere (for instance, segment disclosures)..

+ References+ Details

- Definition

Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary.

+ References

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

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