v3.20.1

Document and Entity Information	Apr. 22, 2020
Document And Entity Information [Line Items]
Entity Registrant Name	IBERIABANK CORP
Amendment Flag	false
Entity Central Index Key	0000933141
Document Type	8-K
Document Period End Date	Apr. 22, 2020
Entity Incorporation State Country Code	LA
Entity File Number	001-37532
Entity Tax Identification Number	72-1280718
Entity Address, Address Line One	200 West Congress Street
Entity Address, City or Town	Lafayette
Entity Address, State or Province	LA
Entity Address, Postal Zip Code	70501
City Area Code	(337)
Local Phone Number	521-4003
Written Communications	true
Soliciting Material	false
Pre Commencement Tender Offer	false
Pre Commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Common Stock [Member]
Document And Entity Information [Line Items]
Security 12b Title	Common Stock (par value $1.00 per share)
Trading Symbol	IBKC
Security Exchange Name	NASDAQ
Series B Preferred Stock [Member]
Document And Entity Information [Line Items]
Security 12b Title	Depositary Shares, Each Representing a 1/400th Interestin a Share of 6.625% Fixed-to-Floating Non-Cumulative Perpetual Preferred Stock, Series B
Trading Symbol	IBKCP
Security Exchange Name	NASDAQ
Series C Preferred Stock [Member]
Document And Entity Information [Line Items]
Security 12b Title	Depositary Shares, Each Representing a 1/400th Interestin a Share of 6.60% Fixed-to-Floating Non-Cumulative Perpetual Preferred Stock, Series C
Trading Symbol	IBKCO
Security Exchange Name	NASDAQ
Series D Preferred Stock [Member]
Document And Entity Information [Line Items]
Security 12b Title	Depositary Shares, Each Representing a 1/400th Interestin a Share of 6.100% Fixed-to-Floating Non-Cumulative Perpetual Preferred Stock, Series D
Trading Symbol	IBKCN
Security Exchange Name	NASDAQ

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

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- Definition

Area code of city

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No definition available.

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- Definition

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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No definition available.

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- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

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- Definition

Address Line 1 such as Attn, Building Name, Street Name

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No definition available.

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Name of the City or Town

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Code for the postal or zip code

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No definition available.

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Name of the state or province.

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No definition available.

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- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation 12B
-Number 240
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- Definition

Indicate if registrant meets the emerging growth company criteria.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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No definition available.

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Two-character EDGAR code representing the state or country of incorporation.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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- Definition

Local phone number for entity.

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No definition available.

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Title of a 12(b) registered security.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name of the Exchange on which a security is registered.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Trading symbol of an instrument as listed on an exchange.

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No definition available.

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Securities Act
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- References

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IBERIABANK CORP 8-K