Iberiabank (IBKC) 10-K 21 Feb 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2016	Feb. 17, 2017	Jun. 30, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Trading Symbol	IBKC
Entity Registrant Name	IBERIABANK CORP
Entity Central Index Key	933,141
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		44,802,973
Entity Public Float			$ 2.4

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Assets
Cash and due from banks	$ 295,896	$ 241,650
Interest-bearing deposits in banks	1,066,230	268,617
Total cash and cash equivalents	1,362,126	510,267
Securities available for sale, at fair value	3,446,097	2,800,286
Securities held to maturity (fair values of $89,932 and $100,961, respectively)	89,216	98,928
Mortgage loans held for sale, at fair value	157,041	166,247
Loans covered by loss share agreements	0	229,217
Non-covered loans, net of unearned income	15,064,971	14,098,211
Total loans, net of unearned income	15,064,971	14,327,428
Allowance for loan losses	(144,719)	(138,378)
Loans, net	14,920,252	14,189,050
FDIC loss share receivables	0	39,878
Premises and equipment, net	306,373	323,902
Goodwill	726,856	724,603
Other assets	651,229	650,907
Total Assets	21,659,190	19,504,068
Deposits:
Non-interest-bearing	4,928,878	4,352,229
Interest-bearing	12,479,405	11,826,519
Total deposits	17,408,283	16,178,748
Short-term borrowings	509,136	326,617
Long-term debt	628,953	340,447
Other liabilities	173,124	159,421
Total Liabilities	18,719,496	17,005,233
Shareholders’ Equity
Carrying Amount	132,097	76,812
Common stock, $1 par value - 100,000,000 shares authorized; 44,795,386 and 41,139,537 shares issued and outstanding, respectively	44,795	41,140
Additional paid-in capital	2,084,446	1,797,982
Retained earnings	704,391	584,486
Accumulated other comprehensive income (loss)	(26,035)	(1,585)
Total Shareholders’ Equity	2,939,694	2,498,835
Total Liabilities and Shareholders’ Equity	$ 21,659,190	$ 19,504,068

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Securities held to maturity, fair values	$ 89,932	$ 100,961
Preferred stock, par value (in usd per share)	$ 1	$ 1
Preferred stock, shares authorized	5,000,000	5,000,000
Liquidation preference (per share)	$ 10,000	$ 10,000
Preferred stock, shares issued	13,750	8,000
Preferred stock, shares outstanding	13,750	8,000
Common stock, par value (in usd per share)	$ 1	$ 1
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	44,795,386	41,139,537
Common stock, shares outstanding	44,795,386	41,139,537

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest and Dividend Income
Loans, including fees	$ 663,037	$ 606,966	$ 526,706
Mortgage loans held for sale, including fees	6,564	6,164	5,153
Investment securities:
Taxable interest	52,150	47,380	38,815
Tax-exempt interest	7,004	5,785	5,862
Amortization of FDIC loss share receivable	(16,024)	(23,500)	(74,617)
Other	4,208	4,063	2,896
Total interest and dividend income	716,939	646,858	504,815
Deposits:
NOW and MMDA	32,396	27,226	18,483
Savings	1,145	740	325
Time deposits	18,039	19,137	14,282
Short-term borrowings	2,453	797	1,364
Long-term debt	13,668	11,200	10,250
Total interest expense	67,701	59,100	44,704
Net interest income	649,238	587,758	460,111
Provision for loan losses	44,424	30,908	19,060
Net interest income after provision for loan losses	604,814	556,850	441,051
Non-interest Income
Mortgage income	83,853	80,662	51,797
Service charges on deposit accounts	44,135	42,197	35,573
Title revenue	22,213	22,837	20,492
Broker commissions	15,338	17,592	18,783
ATM/debit card fee income	14,240	13,989	12,023
Credit card and merchant-related income	12,171	10,675	9,718
Income from bank owned life insurance	5,241	4,356	5,473
Gain on sale of available for sale securities	2,001	1,575	771
Other non-interest income	34,629	26,510	18,998
Total non-interest income	233,821	220,393	173,628
Non-interest Expense
Salaries and employee benefits	331,686	322,586	259,086
Net occupancy and equipment	65,797	68,541	59,571
Communication and delivery	12,383	13,506	12,029
Marketing and business development	12,332	13,176	11,707
Data processing	25,091	34,424	27,249
Professional services	19,153	22,368	18,975
Credit and other loan related expense	10,937	16,653	13,692
Insurance	17,270	16,670	14,359
Loss on early termination of loss share agreements	17,798	0	0
Travel and entertainment	8,481	9,525	9,033
Other non-interest expense	45,737	52,856	47,913
Total non-interest expense	566,665	570,305	473,614
Income before income tax expense	271,970	206,938	141,065
Income tax expense	85,193	64,094	35,683
Net Income	186,777	142,844	105,382
Preferred stock dividends	(7,977)	0	0
Net Income Available to Common Shareholders	178,800	142,844	105,382
Earnings Allocated to Unvested Restricted Stock	(1,872)	(1,680)	(1,651)
Earnings Allocated to Common Shareholders	$ 176,928	$ 141,164	$ 103,731
Earnings per common share - Basic (in usd per share)	$ 4.32	$ 3.69	$ 3.31
Earnings per common share - Diluted (in usd per share)	4.30	3.68	3.30
Cash dividends declared per common share (in usd per share)	$ 1.4	$ 1.36	$ 1.36
Comprehensive Income
Net income	$ 186,777	$ 142,844	$ 105,382
Unrealized gains (losses) on securities:
Unrealized holding gains (losses) arising during the period (net of tax effects of $12,261, $4,374, and $13,202, respectively)	(22,771)	(8,124)	24,517
Reclassification adjustment for gains included in net income (net of tax effects of $700, $551 and $270, respectively)	(1,301)	(1,024)	(501)
Unrealized gains (losses) on securities, net of tax	(24,072)	(9,148)	24,016
Fair value of derivative instruments designated as cash flow hedges:
Change in fair value of derivative instruments designated as cash flow hedges during the period (net of tax effects of $231, $20 and $0, respectively)	(428)	38	0
Reclassification adjustment for losses included in net income (net of tax effects of $27, $0 and $0, respectively)	50	0	0
Fair value of derivative instruments designated as cash flow hedges, net of tax	(378)	38	0
Other comprehensive income (loss), net of tax	(24,450)	(9,110)	24,016
Comprehensive income	$ 162,327	$ 133,734	$ 129,398

Consolidated Statements of Com5

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Unrealized holding gains (losses), taxes	$ 12,261	$ 4,374	$ 13,202
Reclassification adjustment for gains included in net income , taxes	700	551	270
Change in fair value of derivative instruments designated as cash flow hedges, taxes	231	20	0
Reclassification adjustment for losses included in net income, taxes	$ 27	$ 0	$ 0

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($)		Total		Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock at Cost
Beginning balance (in shares) at Dec. 31, 2013				0	31,917,385
Beginning balance at Dec. 31, 2013		$ 1,530,346,000		$ 0	$ 31,917,000	$ 1,178,284,000	$ 435,508,000	$ (16,491,000)	$ (98,872,000)
Increase (Decrease) in Shareholders' Equity
Net income		105,382,000					105,382,000
Other comprehensive income/(loss)		24,016,000						24,016,000
Cash dividends declared		(44,317,000)					(44,317,000)
Reissuance of treasury stock under incentive plans, net of shares surrendered in payment, including tax benefit		10,071,000				3,242,000			6,829,000
Common stock issued for acquisitions (in shares)					3,345,516
Common stock issued for acquisitions		214,665,000			$ 3,346,000	211,319,000
Common stock issued		0				(6,197,000)			6,197,000
Share-based compensation cost		11,985,000				11,985,000
Ending balance (in shares) at Dec. 31, 2014				0	35,262,901
Ending balance at Dec. 31, 2014		1,852,148,000		$ 0	$ 35,263,000	1,398,633,000	496,573,000	7,525,000	(85,846,000)
Increase (Decrease) in Shareholders' Equity
Net income		142,844,000					142,844,000
Other comprehensive income/(loss)		(9,110,000)						(9,110,000)
Cash dividends declared		(54,931,000)					(54,931,000)
Reclassification of treasury stock under the LBCA (in shares)	[1]				(1,809,497)
Reclassification of treasury stock under the LBCA	[1]	0			$ (1,809,000)	(84,037,000)			85,846,000
Common stock issued under incentive plans, net of shares surrendered in payment, including tax benefit (in shares)					211,729
Common stock issued under incentive plans, net of shares surrendered in payment, including tax benefit		2,413,000			$ 212,000	2,201,000
Common stock issued for acquisitions (in shares)					7,474,404
Common stock issued for acquisitions		474,753,000			$ 7,474,000	467,279,000
Shares issued (in shares)				8,000
Preferred stock issued		76,812,000		$ 76,812,000
Share-based compensation cost		13,906,000				13,906,000
Ending balance (in shares) at Dec. 31, 2015				8,000	41,139,537
Ending balance at Dec. 31, 2015		2,498,835,000		$ 76,812,000	$ 41,140,000	1,797,982,000	584,486,000	(1,585,000)	0
Increase (Decrease) in Shareholders' Equity
Net income		186,777,000					186,777,000
Other comprehensive income/(loss)		(24,450,000)						(24,450,000)
Cash dividends declared		(58,895,000)					(58,895,000)
Preferred stock dividends		(7,977,000)	[1]				(7,977,000)
Common stock issued under incentive plans, net of shares surrendered in payment, including tax benefit (in shares)					264,605
Common stock issued under incentive plans, net of shares surrendered in payment, including tax benefit		8,020,000			$ 264,000	7,756,000
Shares issued (in shares)				5,750	3,593,750
Common stock issued		279,242,000			$ 3,594,000	275,648,000
Preferred stock issued		55,285,000		$ 55,285,000
Common stock repurchases (in shares)					(202,506)
Common stock repurchases		(11,666,000)			$ (203,000)	(11,463,000)
Share-based compensation cost		14,523,000				14,523,000
Ending balance (in shares) at Dec. 31, 2016				13,750	44,795,386
Ending balance at Dec. 31, 2016		$ 2,939,694,000		$ 132,097,000	$ 44,795,000	$ 2,084,446,000	$ 704,391,000	$ (26,035,000)	$ 0
[1]	Effective January 1, 2015, companies incorporated in Louisiana became subject to the Louisiana Business Corporation Act (“LBCA”), which eliminates the concept of treasury stock and provides that shares reacquired by a company are to be treated as authorized but unissued. Refer to Note 1 for further discussion.

Consolidated Statements of Sha7

Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash dividends declared per common share (in usd per share)	$ 1.4	$ 1.36	$ 1.36
Retained Earnings
Cash dividends declared per common share (in usd per share)	$ 1.4	$ 1.36	$ 1.36

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash Flows from Operating Activities
Net income	$ 186,777	$ 142,844	$ 105,382
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization, and accretion	5,332	15,457	15,791
Amortization of purchase accounting adjustments, net	(17,431)	(21,635)	7,536
Provision for loan losses	44,424	30,908	19,060
Share-based compensation cost - equity awards	14,523	13,906	11,985
Gain on sale of assets, net	(58)	(2,539)	(14)
Gain on sale of available for sale securities	(2,001)	(1,575)	(771)
Gain on sale of OREO, net	(6,325)	(5,552)	(4,221)
Impairment of FDIC loss share receivables and other long-lived assets	20,883	6,954	6,437
Amortization of premium/discount on securities, net	22,732	18,195	13,793
(Benefit) expense for deferred income taxes	(16,654)	4,551	(25,027)
Originations of mortgage loans held for sale	(2,460,033)	(2,464,588)	(1,675,538)
Proceeds from sales of mortgage loans held for sale	2,525,945	2,516,936	1,720,443
Realized and unrealized gains on mortgage loans held for sale, net	(74,486)	(83,957)	(63,034)
Tax benefit associated with share-based payment arrangements	(1,122)	(580)	(2,105)
Other operating activities, net	64,460	26,798	(10,354)
Net Cash Provided by Operating Activities	306,966	196,123	119,363
Cash Flows from Investing Activities
Proceeds from sales of available for sale securities	197,733	228,604	61,702
Proceeds from maturities, prepayments and calls of available for sale securities	484,138	473,142	488,699
Purchases of available for sale securities	(1,384,525)	(1,063,460)	(703,179)
Proceeds from maturities, prepayments and calls of held to maturity securities	8,791	22,939	36,182
Purchases of held to maturity securities	0	(5,833)	0
Purchases of equity securities	(31,530)	(16,362)	(32,735)
Reimbursement of recoverable covered asset losses (to) from the FDIC	(1,558)	(932)	5,734
Increase in loans, net of loans acquired	(704,025)	(703,946)	(824,437)
Proceeds from sale of premises and equipment	1,941	13,309	5,129
Purchases of premises and equipment, net of premises and equipment acquired	(12,840)	(19,502)	(29,841)
Proceeds from disposition of OREO	33,236	55,025	84,429
Cash paid for additional investment in tax credit entities	(19,208)	(9,671)	(13,191)
Cash received in excess of cash paid for acquisitions	0	425,581	188,803
Other investing activities, net	3,450	30,134	19,950
Net Cash Used in Investing Activities	(1,424,397)	(570,972)	(712,755)
Cash Flows from Financing Activities
Increase in deposits, net of deposits acquired	1,230,008	968,746	641,026
Net change in short-term borrowings, net of borrowings acquired	182,518	(520,653)	110,298
Proceeds from long-term debt	304,728	63,198	54,637
Repayments of long-term debt	(15,025)	(201,259)	(22,871)
Cash dividends paid on common stock	(56,793)	(52,318)	(43,070)
Cash dividends paid on preferred stock	(7,028)	0	0
Net share-based compensation stock transactions	6,899	1,915	7,966
Payments to repurchase common stock	(11,666)	0	0
Net proceeds from issuance of common stock	279,242	0	0
Net proceeds from issuance of preferred stock	55,285	76,812	0
Tax benefit associated with share-based payment arrangements	1,122	580	2,105
Net Cash Provided by Financing Activities	1,969,290	337,021	750,091
Net Increase (Decrease) In Cash and Cash Equivalents	851,859	(37,828)	156,699
Cash and Cash Equivalents at Beginning of Period	510,267	548,095	391,396
Cash and Cash Equivalents at End of Period	1,362,126	510,267	548,095
Supplemental Schedule of Non-cash Activities
Acquisition of real estate in settlement of loans	9,743	21,690	27,050
Common stock issued in acquisition	0	474,753	214,665
Cash paid for:
Interest on deposits and borrowings	70,084	58,556	43,210
Income taxes, net	$ 79,784	$ 53,476	$ 52,094

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES GENERAL The accompanying consolidated financial statements have been prepared in accordance with GAAP and practices generally accepted in the banking industry. The consolidated financial statements include the accounts of the Company and its subsidiaries. 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. Reclassification 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. 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 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 $84 million and $160 million at December 31, 2016 and 2015, 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. 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. NATURE OF OPERATIONS The Company offers commercial and retail banking products and services to customers throughout locations in seven states through IBERIABANK. The Company also operates mortgage production offices in 10 states through 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 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. CDE is engaged in the purchase of tax credits. 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. CONCENTRATION OF CREDIT RISKS Most of the Company’s business activity is with customers located within the states of Louisiana, Florida, Arkansas, Alabama, Texas, Georgia, 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 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 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 does not have any excessive concentrations to any one industry or customer. BUSINESS COMBINATIONS Assets and liabilities acquired in business combinations are recorded at their acquisition date fair values. In accordance with ASC Topic 805, Business Combinations , the Company generally records provisional amounts at the time of acquisition based on the information available to the Company. The provisional estimates of fair values may be adjusted for a period of up to one year (“measurement period”) from the date of acquisition if new information is obtained about facts and circumstances that existed as of the acquisition date that, if known, would have affected the measurement of the amounts recognized as of that date. Subsequent to the Company's early adoption of ASU No. 2015-16 during the third quarter of 2015, adjustments recorded during the measurement period are recognized in the current reporting period. Loans generally represent a significant portion of the assets acquired in the Company’s business acquisitions. If the Company discovers that it has materially underestimated the credit losses expected in the loan portfolio based on information available at the acquisition date within the measurement period, it will reduce or eliminate the gain and/or increase goodwill recorded on the acquisition in the period the adjustment is recorded. If the Company determines that losses arose subsequent to the acquisition date, such losses are reflected as a provision for credit losses. CASH AND CASH EQUIVALENTS For purposes of presentation in the consolidated statements of cash flows, cash and cash equivalents are defined as cash on hand, interest-bearing deposits, and non-interest-bearing demand deposits at other financial institutions with original maturities less than three months . IBERIABANK may be required to maintain average cash balances on hand or with the Federal Reserve Bank to meet regulatory reserve and clearing requirements. At December 31, 2016 and 2015, IBERIABANK had sufficient cash deposited with the Federal Reserve Bank to cover the required reserve balance. INVESTMENT SECURITIES Management determines the appropriate accounting classification of debt and equity securities at the time of acquisition and re-evaluates such designations at least quarterly. Debt securities that management has the ability and intent to hold to maturity are classified as HTM and carried at cost, adjusted for amortization of premiums and accretion of discounts using methods approximating the interest method. Securities acquired with the intention of recognizing short-term profits or which are actively bought and sold are classified as trading securities and reported at fair value, with unrealized gains and losses recognized in earnings. Securities not classified as HTM or trading, including equity securities with readily determinable fair values, are classified as AFS and recorded at fair value, with unrealized gains and losses excluded from earnings and reported in OCI. Credit-related declines in the fair value of debt and marketable equity securities that are considered OTTI are recorded in earnings. The Company evaluates its investment securities portfolio on a quarterly basis for indicators of OTTI. Declines in the fair value of individual HTM and AFS securities below their amortized cost basis are reviewed to determine whether the declines are other than temporary. In estimating OTTI losses, management considers 1) the length of time and the extent to which the fair value has been less than the amortized cost basis, 2) the financial condition and near-term prospects of the issuer, 3) its intent to sell and whether it is more likely than not that the Company would be required to sell those securities before the anticipated recovery of the amortized cost basis, and 4) for debt securities, the recovery of contractual principal and interest. For securities that the Company does not expect to sell, or it is not more likely than not it will be required to sell prior to recovery of its amortized cost basis, the credit component of an OTTI is recognized in earnings and the non-credit component is recognized in OCI. For securities that the Company does expect to sell, or it is more likely than not that it will be required to sell prior to recovery of its amortized cost basis, both the credit and non-credit component of an OTTI are recognized in earnings. Subsequent to recognition of OTTI, an increase in expected cash flows is recognized as a yield adjustment over the remaining expected life of the security based on an evaluation of the nature of the increase. Nonmarketable equity securities include stock acquired for regulatory purposes, such as Federal Home Loan Bank stock and Federal Reserve Bank stock. These securities are accounted for at amortized cost, evaluated for impairment at least quarterly, and included in "other assets". Gains or losses on securities sold are recorded on the trade date, using the specific identification method. LOANS HELD FOR SALE Loans and loan commitments which the Company does not have the intent and ability to hold for the foreseeable future or until maturity or payoff are classified as loans held for sale at the time of origination or acquisition. Subsequent to origination or acquisition, if the Company no longer has the intent or ability to hold a loan for the foreseeable future, generally a decision has been made to sell the loan, and it is classified within loans held for sale. Unless the fair value option has been elected at origination or acquisition, loans classified as held for sale are carried at the lower of cost or fair value. Amortization/accretion of remaining unamortized net deferred loan fees or costs and discounts or premiums (if applicable) ceases when a loan is classified as held for sale. Loans held for sale primarily consist of fixed rate single-family residential mortgage loans originated and committed to be sold in the secondary market. Mortgage loans originated and held for sale are recorded at fair value under the fair value option, unless otherwise noted. For mortgage loans for which the Company has elected the fair value option, gains and losses are included in mortgage income. For any other loans held for sale, net unrealized losses, if any, are recognized through a valuation allowance that is recorded as a charge to non-interest income. See Note 20 for further discussion of the determination of fair value for loans held for sale. In most cases, loans in this category are sold within thirty days and are generally sold with the mortgage servicing rights released. Buyers generally have recourse to return a purchased loan or request reimbursement for the loan premium or servicing rights under limited circumstances. Recourse conditions may include prepayment, payment default, breach of representations or warranties, and documentation deficiencies. During 2016 and 2015, an insignificant number of loans were returned to the Company. At December 31, 2016 and 2015, the recorded repurchase liability associated with transferred loans was not material. LOANS Legacy (Loans originated or renewed and underwritten by the Company) The Company originates mortgage, commercial, and consumer loans for customers. Loans that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at the unpaid principal balances, less the ALL, charge-offs, and unamortized net loan origination fees and direct costs, except for loans carried at fair value. Interest income is accrued as earned over the term of the loans based on the principal balance outstanding. Loan origination fees, net of certain direct origination costs, are deferred and recognized as an adjustment of the related loan yield. Acquired (Loans acquired through Business Combinations) Acquired loans are recorded at fair value on the acquisition date in accordance with ASC Topic 820, Fair Value Measurement , consistent with the exit price concept on the date of acquisition. Credit risk assumptions and any resulting credit discounts are included in the determination of fair value. Therefore, an ALL is not recorded at the acquisition date. The determination of fair value includes estimates related to discount rates, expected prepayments, and the amount and timing of undiscounted expected principal, interest, and other cash flows. Acquired loans are evaluated at acquisition and classified as purchased impaired (“acquired impaired”) or purchased non-impaired (“acquired non-impaired”). Purchased impaired loans reflect credit deterioration since origination to the extent that it is probable at the time of acquisition that the Company will be unable to collect all contractually required payments. At the time of acquisition, purchased impaired loans are accounted for individually or aggregated into loan pools with similar characteristics, which include: • whether the loan is performing according to contractual terms at the time of acquisition, • the loan type based on regulatory reporting guidelines, namely whether the loan was a mortgage, consumer, or commercial loan, • the nature of collateral, • the interest rate type, whether fixed or variable rate, and • the loan payment type, primarily whether the loan is amortizing or interest-only. From these pools, the Company uses certain loan information, including outstanding principal balance, estimated expected losses, weighted average maturity, weighted average term to re-price (if a variable rate loan), weighted average margin, and weighted average interest rate to estimate the expected cash flow for each loan pool. For purchased impaired loans, expected cash flows at the acquisition date in excess of the fair value of loans are recorded as interest income over the life of the loans using a level yield method if the timing and amount of future cash flows is reasonably estimable. For purchased non-impaired loans, the difference between the fair value and unpaid principal balance of the loan at acquisition, referred to as a purchase premium or discount, is amortized or accreted to income over the estimated life of the loans as an adjustment to yield. Subsequent to acquisition, the Company performs cash flow re-estimations at least quarterly for each purchased impaired loan and/or loan pool. Increases in estimated cash flows above those expected at acquisition are recognized on a prospective basis as interest income over the remaining life of the loan and/or pool. Decreases in expected cash flows subsequent to acquisition generally result in recognition of a provision for credit loss. The measurement of cash flows involves several assumptions and judgments (i.e., prepayments, default rates, loss severity, etc.). All of these factors are inherently subjective and significant changes in the cash flow estimations can result over the life of the loan. Classification The Company’s loan portfolio is disaggregated into portfolio segments for purposes of determining the ACL. The Company’s portfolio segments include commercial, residential mortgage, and consumer and other loans, bifurcated between legacy and acquired. The Company further disaggregates each commercial, residential mortgage, and consumer and other loans portfolio segment into classes for purposes of monitoring and assessing credit quality based on certain risk characteristics. Classes within the commercial loan portfolio segment include commercial real estate-construction, commercial real estate-other, commercial and industrial, and energy-related. Classes within the consumer and other loans portfolio segment include consumer-home equity, consumer-indirect automobile, consumer-credit card, and consumer-other. Troubled Debt Restructurings The Company periodically grants concessions to its customers in an attempt to protect as much of its investment as possible and minimize risk of loss. These concessions may include restructuring the terms of a loan to alleviate the burden of the customer’s near-term cash requirements. In order to be classified as a TDR, the Company must conclude that the restructuring constitutes a concession and the customer is experiencing financial difficulties. The Company defines a concession to the customer as a modification of existing terms for economic or legal reasons that it would otherwise not consider. The concession is either granted through an agreement with the customer or is imposed by a court or law. Concessions include modifying original loan terms to reduce or defer cash payments required as part of the loan agreement, including but not limited to: • a reduction of the stated interest rate for the remaining original life of the loan, • extension of the maturity date or dates at a stated interest rate lower than the current market rate for new loans with similar risk characteristics, • reduction of the face amount or maturity amount of the loan as stated in the agreement, or • reduction of accrued interest receivable on the loan. In its determination of whether the customer is experiencing financial difficulties, the Company considers numerous indicators, including, but not limited to: • whether the customer is currently in default on its existing loan(s), or is in an economic position where it is probable the customer will be in default on its loan(s) in the foreseeable future without a modification, • whether the customer has declared or is in the process of declaring bankruptcy, • whether there is substantial doubt about the customer’s ability to continue as a going concern, • whether, based on its projections of the customer’s current capabilities, the Company believes the customer’s future cash flows will be insufficient to service the loan, including interest, in accordance with the contractual terms of the existing agreement for the foreseeable future, and • whether, without modification, the customer cannot obtain sufficient funds from other sources at an effective interest rate equal to the current market rate for a similar loan for a non-troubled debtor. If the Company concludes that both a concession has been granted and the customer is experiencing financial difficulties, the Company identifies the loan as a TDR. All TDRs are considered impaired loans. NON-ACCRUAL AND PAST DUE LOANS (INCLUDING LOAN CHARGE-OFFS) Loans are generally considered past due when contractual payments of principal and interest have not been received within 30 days from the contractual due date. Residential mortgage loans are considered past due when contractual payments have not been received for two consecutive payment dates. Legacy and purchased non-impaired loans are placed on non-accrual status when any of the following occur: 1) the loan is maintained on a cash basis because of deterioration in the financial condition of the borrower; 2) collection of the full contractual amount of principal or interest is not expected (even if the loan is currently paying as agreed); 3) when principal or interest has been in default for a period of 90 days or more, unless the loan is both well secured and in the process of collection; or 4) the borrower has filed or is likely to file bankruptcy. Factors considered in determining the collection of the full contractual amount of principal or interest include assessment of the borrower’s cash flow, valuation of underlying collateral, and the ability and willingness of guarantors to provide credit support. Certain commercial loans are also placed on non-accrual status when payment is not past due and full payment of principal and interest is expected, but we have doubt about the borrower’s ability to comply with existing repayment terms. Consideration will be given to placing a loan on non-accrual due to the deterioration of the debtor’s repayment ability, the repayment of the loan becoming dependent on the liquidation of collateral, an existing collateral deficiency, the loan being classified as "Doubtful" or "Loss", the client filing for bankruptcy, and/or foreclosure being initiated. Regarding all classes within the C&I and CRE portfolios, the determination of a borrower’s ability to make the required principal and interest payments is based on an examination of the borrower’s current financial statements, industry, management capabilities, and other qualitative measures. Purchased impaired loans are placed on non-accrual status when the Company cannot reasonably estimate cash flows on a loan or loan pool. Legacy and purchased non-impaired loans are evaluated for potential charge-off in accordance with the parameters discussed in the following paragraph or when the loan is placed on non-accrual status, whichever is earlier. Loans within the commercial portfolio (except for purchased impaired) are generally evaluated for charge-off at 90 days past due, unless both well-secured and in the process of collection. Closed and open-end residential mortgage and consumer loans (except for purchased impaired) are evaluated for charge-off no later than 120 days past due. Any outstanding loan balance in excess of the fair value of the collateral less costs to sell is charged-off no later than 120 days past due for loans secured by real estate. For non-real estate secured loans, in lieu of charging off the entire loan balance, loans may be written down to the fair value of the collateral less costs to sell if repossession of collateral is assured and in process. The accrual of interest, as well as the amortization/accretion of any remaining unamortized net deferred fees or costs and discount or premium, is discontinued at the time the loan is placed on non-accrual status. All accrued but uncollected interest for loans that are placed on non-accrual status is reversed through interest income. Cash receipts received on non-accrual loans are generally applied against principal until the loan has been collected in full, after which time any additional cash receipts are recognized as interest income (i.e., cost recovery method). However, interest may be accounted for under the cash-basis method as long as the remaining recorded investment in the loan is deemed fully collectible. Loans are returned to accrual status when the borrower has demonstrated a capacity to continue payment of the debt (generally a minimum of six months of payment history) and collection of contractually required principal and interest associated with the debt is reasonably assured. At such time, the accrual of interest and amortization/accretion of any remaining unamortized net deferred fees or costs and discount or premium shall resume. Any interest income which was applied to the principal balance shall not be reversed and subsequently will be recognized as an adjustment to yield over the remaining life of the loan. IMPAIRED LOANS For all classes within the commercial portfolio, all loans with an outstanding commitment balance above a specific threshold are evaluated on a quarterly basis for potential impairment. Generally, residential mortgage and consumer loans within any class are not individually evaluated on a regular basis for impairment. All TDRs, regardless of the outstanding balance amount or portfolio classification, and all purchased impaired loans are considered to be impaired. A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal and/or interest when due, according to the contractual terms of the loan agreement. Factors considered by management in determining impairment include payment status, collateral value, and the likelihood of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired. Impairment losses are measured on a loan-by-loan basis for commercial and certain residential mortgage or consumer loans, based on either the present value of expected future cash flows discounted at the loan’s effective interest rate, the loan’s observable market price, or the fair value of the collateral if the loan is collateral-dependent. This measurement requires significant judgment and use of estimates, and the actual loss ultimately recognized by the Company may differ significantly from the estimates. ALLOWANCE FOR CREDIT LOSSES The Company maintains the ACL at a level that management believes appropriate to absorb estimated probable credit losses incurred in the loan portfolios (including unfunded commitments) as of the consolidated balance sheet date. The ACL consists of the allowance for loan losses (contra asset) and the reserve for unfunded commitments (liability). The manner in which the ACL is determined is based on 1) the accounting method applied to the underlying loans and 2) whether the loan is required to be measured for impairment. The Company delineates between loans accounted for under the contractual yield method, legacy and purchased non-impaired loans, and purchased impaired loans. Further, for legacy and acquired non-impaired loans, the Company attributes portions of the ACL to loans and loan commitments that it measures individually, and groups of homogeneous loans and loan commitments that it measures collectively for impairment. Determination of the appropriate ACL involves a high degree of complexity and requires significant judgment regarding the credit quality of the loan portfolio. Several factors are taken into consideration in the determination of the overall ACL, including a qualitative component. These factors include, but are not limited to, the overall risk profiles of the loan portfolios, net charge-off experience, the extent of impaired loans, the level of non-accrual loans, the level of 90 days past due loans, the value of collateral, the ability to monetize guarantor support, and the overall percentage level of the allowance relative to the loan portfolio, amongst other factors. The Company also considers overall asset quality trends, changes in lending practices and procedures, trends in the nature and volume of the loan portfolio, including the existence and effect of any portfolio concentrations, changes in experience and depth of lending staff, the Company’s legal, regulatory and competitive environment, national and regional economic trends, data availability and applicability that might impact the portfolio or the manner in which it estimates losses, and risk rating accuracy and risk identification. The allowance for loan losses for all impaired loans (excluding purchased impaired) is determined on an individual loan basis, considering the facts and circumstances specific to each borrower. The allowance is based on the difference between the recorded investment in the loan and generally either the estimated net present value of projected cash flows or the estimated value of the collateral associated with the loan, if the loan is deemed collateral-dependent. For non-impaired loans (excluding purchased impaired), the allowance for loan losses is calculated based on pools of loans with similar characteristics. The pool-level allowance is calculated through the application of PD (i.e., probability of default) and LGD (i.e., loss given default) factors for each individual loan. PDs and LGDs are determined based on historical default and loss information for similar loans. For purposes of establishing estimated loss percentages for pools of loans that share common risk characteristics, the Company’s loan portfolio is segmented by various loan characteristics including loan type, risk rating (commercial), Vantage or FICO score (residential mortgage and consumer), past due status (residential mortgage and consumer) and call report code. The default and loss information is measured over an appropriate period for each loan pool and adjusted as deemed appropriate. Qualitative adjustments are incorporated into the pool-level analysis to accommodate for the imprecision of certain assumptions and uncertainties inherent in the calculation. See the "Loans" section of this Footnote for discussion of the determination of the ACL for purchased impaired loans. Certain inherent, but unconfirmed losses are probable within the loan portfolio. The Company’s current methodology for determining the level of inherent losses is based on historical loss rates, current credit grades, specific allocation, and other qualitative adjustments. In a stable or deteriorating credit environment, heavy reliance on historical loss rates and the credit grade rating process results in model-derived reserves that tend to slightly lag behind portfolio deterioration. Similar lags can occur in an improving credit environment whereby required reserves can lag slightly behind portfolio improvement. Given these and other model limitations, qualitative adjustment factors may be incremental or decremental to the quantitative model results. In periods prior to 2015, the Company estimated incurred losses on its Exploration and Production and its Oil Field Services portfolios as an aggregate portfolio. Beginning in 2015, as the performance of these two portfolios began to diverge, the Company disaggregated the analysis of incurred losses within these portfolios, which included modifying its LGD estimates for the portfolios to more closely align with published historical industry data and other factors. Absent this change, the Company would have recorded an additional $10.0 million , or 17 cents per share, in provision expense for the year ended December 31, 2015. The reserve for unfunded commitments is determined using similar methodologies described above for non-impaired loans. The loss factors used in the reserve for unfunded commitments are equivalent to the loss factors used in the allowance for loan losses, while also considering utilization of unused commitments. FDIC LOSS SHARE RECEIVABLE The Company entered into or assumed arrangements with the FDIC which obligated the FDIC to reimburse the Company for losses on certain loans associated with FDIC-assisted transactions. The indemnification assets were recorded at fair value as of the acquisition dates based on estimated cash flows to be received over the expected life of the acquired assets, not to exceed the term of the indemnification agreements. Effective as of December 20, 2016, the Company entered into an agreement with the FDIC to terminate the Company’s twelve loss share agreements ahead of their contractual maturities. Under the terms of the agreement, all rights and obligations of the Company and FDIC have been resolved and completed. The Company received a net payment of $6.5 million from the FDIC as consideration for termination of the loss share agreements and subsequently derecognized the remaining FDIC indemnification asset of $20.4 million , along with other transaction related-adjustments (including tax impacts), resulting in a net loss of $11.2 million . PREMISES AND EQUIPMENT Land is carried at cost. Buildings, furniture, fixtures, and equipment are carried at cost, less accumulated depreciation computed on a straight-line basis over the estimated useful lives of 10 to 40 years for buildings and related improvements and generally 3 to 20 years for furniture, fixtures, and equipment. Leasehold improvements are amortized over the lease term, including any renewal periods that are reasonably assured, or the asset’s useful life, whichever is shorter. Premises and equipment are evaluated for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. SOFTWARE Software is amortized on a straight-line basis over its estimated useful life. The estimated useful life of software is generally three years , but

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2016
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	RECENT ACCOUNTING PRONOUNCEMENTS ASU No. 2014-09 In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers , which implements a common revenue standard and clarifies the principles used for recognizing revenue. The amendments in the ASU clarify that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. As part of that principle, the entity should identify the contract(s) with the customer, identify the performance obligation(s) of the contract, determine the transaction price, allocate that transaction price to the performance obligation(s), and then recognize revenue when or as the entity satisfies the performance obligation(s). The amendments also provide additional guidance/principles associated with gross vs. net presentation (i.e., principal versus agency considerations). The amendments in ASU No. 2014-09 will be effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that annual reporting period. The amendments will be applied through the election of one of two retrospective methods. The Company intends to adopt the amendments beginning January 1, 2018 through the modified-retrospective transition method. Based on the Company’s preliminary scoping, walkthroughs, and contract reviews, it does not expect to recognize a significant cumulative adjustment to equity upon implementation of the standard. Further, the Company does not expect a significant impact to the Company’s consolidated statements of comprehensive income or consolidated balance sheets from either a presentation or timing perspective, but is still analyzing some contracts (e.g., card interchange and rewards). The Company does anticipate additional disclosures will be presented in the notes to the consolidated financial statements following adoption. ASU No. 2015-02 In February 2015, the FASB issued ASU No. 2015-02, Consolidation - Amendments to the Consolidation Analysis , which changes the analysis that a reporting entity must perform to determine whether it should consolidate certain types of legal entities. The amendments in the guidance: 1) modify the evaluation of whether limited partnerships and similar legal entities are variable interest entities or voting interest entities, 2) eliminate the presumption that a general partner should consolidate a limited partnership, 3) affect the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships, and 4) provide a scope exception from consolidation guidance for certain investment funds. The Company adopted the amendment, effective January 1, 2016, through retrospective application on all existing agreements; however, there was no resulting change to amounts reported in prior periods. Refer to Note 1 for current principles of consolidation. ASU No. 2015-05 In April 2015, the FASB issued new accounting guidance related to whether a cloud computing arrangement includes a software license (ASU No. 2015-05, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement). If a cloud computing arrangement includes a software license, the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. The Company adopted the amendment prospectively on all arrangements entered into or materially modified beginning January 1, 2016, on an individual arrangement basis. The impact of the adoption of ASU 2015-05 was not material to the Company’s consolidated financial statements. ASU No. 2016-01 In January 2016, the FASB issued ASU No. 2016-01, Financial Statements - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The amendments will not change the guidance for classifying and measuring investments in debt securities or loans; however, the ASU will impact how entities measure certain equity investments, recognize changes in the fair value of financial liabilities measured under the fair value option that are attributable to instrument-specific credit risk, and disclose and present financial assets and liabilities in financial statements. Specifically, the aforementioned amendments will require measurement of equity investments at fair value, with changes recognized in net income, unless the investments qualify for the new practicability exception, the equity method of accounting, or consolidation. For financial liabilities measured using the fair value option, any change in fair value caused by a change in an entity’s own credit risk will be recognized separately in OCI, as opposed to earnings. The amendments will also require entities to present financial assets and financial liabilities separately, grouped by measurement category and form of financial asset in the statement of financial position or in the accompanying notes to the financial statements. Entities will also no longer have to disclose the methods and significant assumptions for financial instruments measured at amortized cost, but will be required to measure such instruments under the “exit price” notion for disclosure purposes. ASU No. 2016-01 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. An entity will record a cumulative-effect adjustment to beginning retained earnings as of the beginning of the first reporting period in which the guidance is adopted, with two exceptions. The amendments related to equity investments without readily determinable fair values (including disclosure requirements) will be effective prospectively. The requirement to use the exit price notion to measure the fair value of financial instruments for disclosure purposes will also be applied prospectively. The Company does not expect a significant cumulative-effect adjustment to be recorded at adoption or any significant impact to the consolidated financial statements associated with the accounting for its current equity investments. The Company does anticipate financial statement disclosures to be impacted, specifically related to financial instruments measured at amortized cost whose fair values are disclosed under the “entry price” notion, but is currently still in the process of determining the impact. ASU No. 2016-02 In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842 ). The most significant amendment to existing GAAP is the recognition of lease assets (i.e., right of use assets) and liabilities on the balance sheet for leases that are classified as operating leases by lessees. The lessor model remains similar to the current accounting model in existing GAAP. Additional amendments include, but are not limited to, the elimination of leveraged leases; modification to the definition of a lease; amendments on sale and leaseback transactions; and disclosure of additional quantitative and qualitative information. ASU 2016-02 will be effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The Company anticipates adopting the amendments on January 1, 2019. The Company is currently assessing the practical expedients it may elect at adoption, but does not anticipate the amendments will have a significant impact to the consolidated financial statements. Based on the Company’s preliminary analysis of its current portfolio, the impact to the Company’s consolidated balance sheets is estimated to result in less than a 1% increase in assets and liabilities. The adjustment to retained earnings is not expected to be material based on the transition guidance associated with current sale-leaseback agreements. The Company also anticipates additional disclosures to be provided at adoption. ASU No. 2016-09 In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . The amendments will require recognition of excess tax benefits and deficiencies associated with awards which vest or settle within income tax expense or benefit in the statement of comprehensive income, with the tax effects treated as discrete items in the reporting period in which they occur. The ASU further requires entities to recognize excess tax benefits regardless of whether the benefit reduces taxes payable in the current period. This will eliminate the current APIC pool concept. The amendments will also allow an accounting policy election to account for forfeitures as they occur, permit an entity to withhold up to the maximum statutory tax rates in the applicable jurisdictions while still qualifying for equity classification, and change the classification of certain cash flows associated with stock compensation. ASU 2016-09 will be effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The transition method for implementing each amendment varies. The Company expects to elect an accounting policy to account for forfeitures as they occur upon adoption. Based on the Company's current stock valuation and estimated exercise activity associated with stock options, it anticipates an insignificant reduction to income tax expense at adoption. ASU No. 2016-13 In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The amendments introduce an impairment model that is based on expected credit losses (“ECL”), rather than incurred losses, to estimate credit losses on certain types of financial instruments (e.g., loans and held-to-maturity securities), including certain off-balance sheet financial instruments (e.g., loan commitments). The ECL should consider historical information, current information, and reasonable and supportable forecasts, including estimates of prepayments, over the contractual term. Financial instruments with similar risk characteristics may be grouped together when estimating the ECL. The ASU also amends the current AFS security impairment model for debt securities. The new model will require an estimate of ECL when the fair value is below the amortized cost of the asset through the use of an allowance to record estimated credit losses (and subsequent recoveries). Non-credit related losses will continue to be recognized through OCI. In addition, the amendments provide for a simplified accounting model for purchased financial assets with a more-than-insignificant amount of credit deterioration since their origination. The initial estimate of expected credit losses would be recognized through an ALL with an offset (i.e., increase) to the cost basis of the related financial asset at acquisition. ASU 2016-13 will be effective for fiscal years beginning after December 15, 2019, including interim periods. The amendments will be applied through a modified-retrospective approach, resulting in a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective. A prospective transition approach is required for debt securities for which OTTI had been recognized before the effective date. Amounts previously recognized in AOCI as of the date of adoption that relate to improvements in cash flows expected to be collected should continue to be accreted into income over the remaining life of the asset. Recoveries of amounts previously written off relating to improvements in cash flows after the date of adoption should be recorded in earnings when received. The Company is currently evaluating the impact of the ASU on the Company’s consolidated financial statements. ASU No. 2016-15 In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments , in order to reduce current diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. ASU 2016-15 will be effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. The amendments should be applied using a retrospective transition method to each period presented. The Company is currently evaluating the impact of the ASU on the Company’s consolidated statement of cash flows. The Company is not expecting to early adopt the ASU. ASU No. 2017-01 In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business , which introduces amendments that are intended to clarify the definition of a business to assist companies and other reporting organizations with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The amendments are intended to narrow the current interpretation of a business. ASU No. 2017-01 will be effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within those periods. The amendments will be applied prospectively on or after the effective date. Early application of the amendments in this ASU is allowed for transactions, including when a subsidiary or group of assets is deconsolidated/derecognized, in which the acquisition date occurs before the issuance date or effective date of the amendments, only when the transaction has not been reported in financial statements that have been issued or made available for issuance. The Company is currently evaluating the effect of the ASU. ASU No. 2017-04 In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment, which simplifies how an entity is required to test goodwill for impairment by eliminating Step 2 from the goodwill impairment test. Therefore, any carrying amount which exceeds the reporting unit’s fair value (up to the amount of goodwill recorded) will be recognized as an impairment loss. ASU No. 2017-04 will be effective for annual reporting periods beginning after December 15, 2019, including interim reporting periods within those periods. The amendments will be applied prospectively on or after the effective date. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Based on recent goodwill impairments tests, which did not require the application of Step 2, the Company does not expect the adoption of this ASU to have an immediate impact.

Acquisition Activity

Acquisition Activity	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Acquisition Activity	ACQUISITION ACTIVITY 2015 Acquisitions During 2015, the Company expanded its presence in Florida and Georgia through acquisitions of Florida Bank Group, Inc. on February 28, 2015, Old Florida Bancshares, Inc. on March 31, 2015, and Georgia Commerce Bancshares, Inc. on May 31, 2015. The Company accounts for business combinations under the acquisition method in accordance with ASC Topic 805, Business Combinations. Accordingly, for each transaction the purchase price is allocated to the fair value of the assets acquired and liabilities assumed as of the date of acquisition. Upon receipt of final fair value estimates during the measurement period, which must be within one year of the acquisition dates, the Company records any adjustments to the preliminary fair value estimates in the reporting period in which the adjustments are determined. During the first quarter of 2016, the Company finalized the purchase price allocations related to the Florida Bank Group and Old Florida acquisitions. During the second quarter of 2016, the Company finalized the purchase price allocation related to the Georgia Commerce acquisition. The impact of these adjustments during 2016 was a $2.3 million increase to goodwill, with an offsetting decrease to net deferred tax assets. The following tables summarize the consideration paid, allocation of purchase price to net assets acquired and resulting goodwill for the aforementioned acquisitions. Acquisition of Florida Bank Group, Inc. (Dollars in thousands) Number of Shares Amount Equity consideration Common stock issued 752,493 $ 47,497 Total equity consideration 47,497 Non-Equity consideration Cash 42,988 Total consideration paid 90,485 Fair value of net assets assumed including identifiable intangible assets 73,043 Goodwill $ 17,442 (Dollars in thousands) As Acquired Fair Value Adjustments As recorded by the Company Assets Cash and cash equivalents $ 72,982 $ — $ 72,982 Investment securities 107,236 136 (1) 107,372 Loans 312,902 (5,371 ) (2) 307,531 Other real estate owned 498 (75 ) (3) 423 Core deposit intangible — 4,489 (4) 4,489 Deferred tax asset, net 18,151 8,569 (5) 26,720 Other assets 29,817 (8,949 ) (6) 20,868 Total Assets $ 541,586 $ (1,201 ) $ 540,385 Liabilities Interest-bearing deposits $ 282,417 $ 263 (7) $ 282,680 Non-interest-bearing deposits 109,548 — 109,548 Borrowings 60,000 8,598 (8) 68,598 Other liabilities 1,898 4,618 (9) 6,516 Total Liabilities $ 453,863 $ 13,479 $ 467,342 Explanation of certain fair value adjustments: (1) The amount represents the adjustment of the book value of Florida Bank Group’s investments to their estimated fair value on the date of acquisition. (2) The amount represents the adjustment of the book value of Florida Bank Group's loans to their estimated fair values based on acquisition date interest rates and expected cash flows, which includes estimates of expected credit losses inherent in the portfolio. (3) The adjustment represents the adjustment of Florida Bank Group's OREO to its estimated fair value less costs to sell on the date of acquisition. (4) The amount represents the fair value of the core deposit intangible asset created in the acquisition. (5) The amount represents the net deferred tax asset recognized on the fair value adjustments of Florida Bank Group acquired assets and assumed liabilities. (6) The amount represents the adjustment of the book value of Florida Bank Group’s property, equipment, and other assets to their estimated fair value at the acquisition date based on their appraised value. (7) The amount represents the adjustment of the book value of Florida Bank Group's time deposits to their estimated fair values at the date of acquisition. (8) The amount represents the adjustment of the book value of Florida Bank Group’s borrowings to their estimated fair value based on acquisition date interest rates and the credit characteristics inherent in the liability. (9) The amount is necessary to record Florida Bank Group's rent liability at fair value. Acquisition of Old Florida Bancshares, Inc. (Dollars in thousands) Number of Shares Amount Equity consideration Common stock issued 3,839,554 $ 242,007 Total equity consideration 242,007 Non-Equity consideration Cash 11,145 Total consideration paid 253,152 Fair value of net assets assumed including identifiable intangible assets 152,375 Goodwill $ 100,777 (Dollars in thousands) As Acquired Fair Value Adjustments As recorded by the Company Assets Cash and cash equivalents $ 360,688 $ — $ 360,688 Investment securities 67,209 — 67,209 Loans held for sale 5,952 — 5,952 Loans 1,073,773 (10,822 ) (1) 1,062,951 Other real estate owned 4,515 1,449 (2) 5,964 Core deposit intangible — 6,821 (3) 6,821 Deferred tax asset, net 9,490 4,388 (4) 13,878 Other assets 30,549 (7,238 ) (5) 23,311 Total Assets $ 1,552,176 $ (5,402 ) $ 1,546,774 Liabilities Interest-bearing deposits $ 1,048,765 $ 123 (6) $ 1,048,888 Non-interest-bearing deposits 340,869 — 340,869 Borrowings 1,528 — 1,528 Other liabilities 3,038 76 (7) 3,114 Total Liabilities $ 1,394,200 $ 199 $ 1,394,399 Explanation of certain fair value adjustments: (1) The amount represents the adjustment of the book value of Old Florida's loans to their estimated fair values based on acquisition date interest rates and expected cash flows, which includes estimates of expected credit losses inherent in the portfolio. (2) The adjustment represents the adjustment of Old Florida's OREO to its estimated fair value less costs to sell on the date of acquisition. (3) The amount represents the fair value of the core deposit intangible asset created in the acquisition. (4) The amount represents the net deferred tax asset recognized on the fair value adjustment of Old Florida acquired assets and assumed liabilities. (5) The amount represents the adjustment of the book value of Old Florida’s property, equipment, and other assets to their estimated fair value at the acquisition date based on their appraised value. (6) The amount represents the adjustment of the book value of Old Florida's time deposits to their estimated fair values on the date of acquisition. (7) The adjustment is necessary to record Old Florida's rent liability at fair value. Acquisition of Georgia Commerce Bancshares, Inc (Dollars in thousands) Number of Shares Amount Equity consideration Common stock issued 2,882,357 $ 185,249 Total equity consideration 185,249 Non-Equity consideration Cash 5,015 Total consideration paid 190,264 Fair value of net assets assumed including identifiable intangible assets 103,569 Goodwill $ 86,695 (Dollars in thousands) As Acquired Fair Value As recorded by Assets Cash and cash equivalents $ 51,059 $ — $ 51,059 Investment securities 135,710 (807 ) (1) 134,903 Loans held for sale 1,249 — 1,249 Loans 807,726 (15,607 ) (2) 792,119 Other real estate owned 9,795 (4,207 ) (3) 5,588 Core deposit intangible — 6,720 (4) 6,720 Deferred tax asset, net 3,603 5,452 (5) 9,055 Other assets 28,956 (657 ) (6) 28,299 Total Assets $ 1,038,098 $ (9,106 ) $ 1,028,992 Liabilities Interest-bearing deposits 658,133 176 (7) 658,309 Non-interest-bearing deposits 249,739 — 249,739 Borrowings 13,204 — 13,204 Other liabilities 4,171 — 4,171 Total Liabilities $ 925,247 $ 176 $ 925,423 Explanation of certain fair value adjustments: (1) The amount represents the adjustment of the book value of Georgia Commerce’s investments to their estimated fair value on the date of acquisition. (2) The amount represents the adjustment of the book value of Georgia Commerce's loans to their estimated fair value based on acquisition date interest rates and expected cash flows, which includes estimates of expected credit losses inherent in the portfolio. (3) The adjustment represents the adjustment of Georgia Commerce's OREO to its estimated fair value less costs to sell on the date of acquisition. (4) The amount represents the fair value of the core deposit intangible asset created in the acquisition. (5) The amount represents the net deferred tax asset recognized on the fair value adjustment of Georgia Commerce acquired assets and assumed liabilities. (6) The amount represents the adjustment of the book value of Georgia Commerce’s property, equipment, and other assets to their estimated fair value at the acquisition date based on their appraised value. (7) The amount represents the adjustment of the book value of Georgia Commerce's time deposits to their estimated fair values at the date of acquisition. There were no acquisitions during the year ended December 31, 2016.

Investment Securities

Investment Securities	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Investment Securities	INVESTMENT SECURITIES The amortized cost and fair values of investment securities, with gross unrealized gains and losses, consist of the following: December 31, 2016 (Dollars in thousands) Amortized Gross Gross Estimated Securities available for sale: U.S. Government-sponsored enterprise obligations $ 212,662 $ 245 $ (549 ) $ 212,358 Obligations of state and political subdivisions 286,458 1,948 (5,207 ) 283,199 Mortgage-backed securities 2,888,180 4,820 (41,291 ) 2,851,709 Other securities 98,974 361 (504 ) 98,831 Total securities available for sale $ 3,486,274 $ 7,374 $ (47,551 ) $ 3,446,097 Securities held to maturity: Obligations of state and political subdivisions $ 64,726 $ 1,609 $ (133 ) $ 66,202 Mortgage-backed securities 24,490 57 (817 ) 23,730 Total securities held to maturity $ 89,216 $ 1,666 $ (950 ) $ 89,932 December 31, 2015 (Dollars in thousands) Amortized Gross Gross Estimated Securities available for sale: U.S. Government-sponsored enterprise obligations $ 252,514 $ 1,161 $ (1,592 ) $ 252,083 Obligations of state and political subdivisions 182,541 5,429 (9 ) 187,961 Mortgage-backed securities 2,272,879 8,457 (16,523 ) 2,264,813 Other securities 95,496 430 (497 ) 95,429 Total securities available for sale $ 2,803,430 $ 15,477 $ (18,621 ) $ 2,800,286 Securities held to maturity: Obligations of state and political subdivisions $ 69,979 $ 2,803 $ (101 ) $ 72,681 Mortgage-backed securities 28,949 107 (776 ) 28,280 Total securities held to maturity $ 98,928 $ 2,910 $ (877 ) $ 100,961 Securities with carrying values of $1.5 billion and $1.4 billion were pledged to secure public deposits and other borrowings at December 31, 2016 and 2015 , respectively. Information pertaining to securities with gross unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous loss position, is as follows: December 31, 2016 Less Than Twelve Months Over Twelve Months Total (Dollars in thousands) Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Securities available for sale: U.S. Government-sponsored enterprise obligations $ (549 ) $ 150,554 $ — $ — $ (549 ) $ 150,554 Obligations of state and political obligations (5,207 ) 148,059 — — (5,207 ) 148,059 Mortgage-backed securities (38,667 ) 2,191,563 (2,624 ) 98,912 (41,291 ) 2,290,475 Other Securities (451 ) 36,484 (53 ) 3,850 (504 ) 40,334 Total securities available for sale $ (44,874 ) $ 2,526,660 $ (2,677 ) $ 102,762 $ (47,551 ) $ 2,629,422 Securities held to maturity: Obligations of state and political obligations $ (133 ) $ 10,602 $ — $ — $ (133 ) $ 10,602 Mortgage-backed securities (330 ) 12,288 (487 ) 10,960 (817 ) 23,248 Total securities held to maturity $ (463 ) $ 22,890 $ (487 ) $ 10,960 $ (950 ) $ 33,850 December 31, 2015 Less Than Twelve Months Over Twelve Months Total (Dollars in thousands) Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Securities available for sale: U.S. Government-sponsored enterprise obligations $ (1,214 ) $ 177,839 $ (378 ) $ 28,116 $ (1,592 ) $ 205,955 Obligations of state and political obligations (9 ) 5,765 — — (9 ) 5,765 Mortgage-backed securities (11,737 ) 1,279,914 (4,786 ) 185,215 (16,523 ) 1,465,129 Other Securities (488 ) 51,975 (9 ) 499 (497 ) 52,474 Total securities available for sale $ (13,448 ) $ 1,515,493 $ (5,173 ) $ 213,830 $ (18,621 ) $ 1,729,323 Securities held to maturity: Obligations of state and political obligations $ (9 ) $ 1,999 $ (92 ) $ 4,162 $ (101 ) $ 6,161 Mortgage-backed securities (45 ) 3,530 (731 ) 17,573 (776 ) 21,103 Total securities held to maturity $ (54 ) $ 5,529 $ (823 ) $ 21,735 $ (877 ) $ 27,264 The Company assessed the nature of the unrealized losses in its portfolio as of December 31, 2016 and 2015 to determine if there are losses that should be deemed other-than-temporary. In its analysis of these securities, management considered numerous factors to determine whether there were instances where the amortized cost basis of the debt securities would not be fully recoverable, including, but not limited to: • The length of time and extent to which the estimated fair value of the securities was less than their amortized cost, • Whether adverse conditions were present in the operations, geographic area, or industry of the issuer, • The payment structure of the security, including scheduled interest and principal payments, including the issuer’s failures to make scheduled payments, if any, and the likelihood of failure to make scheduled payments in the future, • Changes to the rating of the security by a rating agency, and • Subsequent recoveries or additional declines in fair value after the balance sheet date. Management believes it has considered these factors, as well as all relevant information available, when determining the expected future cash flows of the securities in question. In each instance, management has determined the cost basis of the securities would be fully recoverable. Management also has the intent to hold debt securities until their maturity or anticipated recovery if the security is classified as available for sale. In addition, management does not believe the Company will be required to sell debt securities before the anticipated recovery of the amortized cost basis of the security. As a result of the Company's analysis, no declines in the estimated fair value of the Company's investment securities were deemed to be other-than-temporary at December 31, 2016 or 2015 . At December 31, 2016 , 397 debt securities had unrealized losses of 1.79% of the securities’ amortized cost basis. At December 31, 2015 , 252 debt securities had unrealized losses of 1.10% of the securities’ amortized cost basis. The unrealized losses for each of the securities related to market interest rate changes and not credit concerns of the issuers. Additional information on securities that have been in a continuous loss position for over twelve months at December 31 is presented in the following table. (Dollars in thousands) 2016 2015 Number of securities Issued by Fannie Mae, Freddie Mac, or Ginnie Mae 28 40 Issued by political subdivisions — 2 Other 3 1 31 43 Amortized Cost Basis Issued by Fannie Mae, Freddie Mac, or Ginnie Mae $ 112,983 $ 236,800 Issued by political subdivisions — 4,253 Other 3,903 508 $ 116,886 $ 241,561 Unrealized Loss Issued by Fannie Mae, Freddie Mac, or Ginnie Mae $ 3,111 $ 5,895 Issued by political subdivisions — 92 Other 53 9 $ 3,164 $ 5,996 The Fannie Mae, Freddie Mac, and Ginnie Mae securities are rated AA+ by S&P and Aaa by Moodys. The amortized cost and estimated fair value of investment securities by maturity at December 31, 2016 are presented in the following table. Securities are classified according to their contractual maturities without consideration of principal amortization, potential prepayments or call options. Accordingly, actual maturities may differ from contractual maturities. Weighted average yields are calculated on the basis of the yield to maturity based on the amortized cost of each security. Securities Available for Sale Securities Held to Maturity (Dollars in thousands) Weighted Amortized Estimated Weighted Amortized Estimated Within one year or less 2.29 % $ 15,540 $ 15,477 2.59 % $ 2,551 $ 2,570 One through five years 1.65 283,914 284,150 2.95 9,903 10,082 After five through ten years 2.25 703,768 697,829 3.07 18,181 18,569 Over ten years 2.05 2,483,052 2,448,641 2.81 58,581 58,711 2.06 % $ 3,486,274 $ 3,446,097 2.88 % $ 89,216 $ 89,932 The following is a summary of realized gains and losses from the sale of securities classified as available for sale. Gains or losses on securities sold are recorded on the trade date, using the specific identification method. Years Ended December 31 (Dollars in thousands) 2016 2015 2014 Realized gains $ 2,949 $ 1,834 $ 863 Realized losses (948 ) (259 ) (92 ) $ 2,001 $ 1,575 $ 771 In addition to the gains above, the Company realized certain gains on calls of securities held to maturity that were not significant to the consolidated financial statements. Other Equity Securities The Company accounts for the following securities at amortized cost, which approximates fair value, in “other assets” on the consolidated balance sheets at December 31: (Dollars in thousands) 2016 2015 Federal Home Loan Bank (FHLB) stock $ 42,326 $ 16,265 Federal Reserve Bank (FRB) stock 48,584 48,584 Other investments 2,808 1,159 $ 93,718 $ 66,008

Loans

Loans	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Loans	90 days Total Past Due Non-accrual Loans Total Loans Commercial real estate - Construction $ 740,761 $ — $ — $ — $ — $ — $ 740,761 Commercial real estate - Other 4,863,902 1,861 351 — 2,212 16,439 4,882,553 Commercial and industrial 3,158,700 3,999 870 — 4,869 31,227 3,194,796 Energy-related 407,434 — 1,526 — 1,526 150,329 559,289 Residential mortgage 836,509 2,012 1,577 1,104 4,693 13,014 854,216 Consumer - Home equity 1,768,763 5,249 1,430 — 6,679 7,979 1,783,421 Consumer - Indirect automobile 127,054 2,551 405 — 2,956 1,038 131,048 Consumer - Credit card 81,602 199 99 — 298 624 82,524 Consumer - Other 462,650 2,155 618 — 2,773 893 466,316 Total $ 12,447,375 $ 18,026 $ 6,876 $ 1,104 $ 26,006 $ 221,543 $ 12,694,924 December 31, 2015 Legacy loans Accruing (Dollars in thousands) Current or less than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Total Loans Commercial real estate - Construction $ 635,560 $ 801 $ — $ — $ 801 $ 120 $ 636,481 Commercial real estate - Other 3,848,584 2,687 793 95 3,575 15,422 3,867,581 Commercial and industrial 2,943,409 1,208 739 87 2,034 6,659 2,952,102 Energy-related 670,081 15 — — 15 7,081 677,177 Residential mortgage 676,347 1,075 2,485 442 4,002 13,674 694,023 Consumer - Home equity 1,565,596 3,549 870 — 4,419 5,628 1,575,643 Consumer - Indirect automobile 242,328 2,187 518 — 2,705 1,181 246,214 Consumer - Credit card 76,360 394 113 — 507 394 77,261 Consumer - Other 460,594 1,923 752 — 2,675 769 464,038 Total $ 11,118,859 $ 13,839 $ 6,270 $ 624 $ 20,733 $ 50,928 $ 11,190,520 December 31, 2016 Acquired loans (1) (2) Accruing (Dollars in thousands) Current or Less Than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Discount/Premium Acquired Impaired Loans Total Loans Commercial real estate - Construction $ 26,714 $ — $ — $ — $ — $ 1,946 $ (243 ) $ 32,991 $ 61,408 Commercial real estate - Other 871,492 716 55 32 803 1,221 (3,649 ) 247,677 1,117,544 Commercial and industrial 314,990 73 51 — 124 1,317 (837 ) 32,732 348,326 Energy-related 1,910 — — — — — (6 ) — 1,904 Residential mortgage 290,031 328 989 — 1,317 719 (1,835 ) 122,952 413,184 Consumer - Home equity 286,411 1,078 189 250 1,517 1,395 (5,237 ) 88,419 372,505 Consumer - Indirect automobile — — — — — — — 4 4 Consumer - Credit Card 468 — — — — — — — 468 Consumer - Other 49,449 391 97 — 488 360 (1,004 ) 5,411 54,704 Total $ 1,841,465 $ 2,586 $ 1,381 $ 282 $ 4,249 $ 6,958 $ (12,811 ) $ 530,186 $ 2,370,047 December 31, 2015 Acquired loans (1) (2) Accruing (Dollars in thousands) Current or Less Than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Discount/Premium Acquired Impaired Loans Total Loans Commercial real estate - Construction $ 69,167 $ 180 $ 117 $ — $ 297 $ — $ (358 ) $ 56,320 $ 125,426 Commercial real estate - Other 1,090,688 861 705 — 1,566 1,491 (4,479 ) 354,757 1,444,023 Commercial and industrial 442,454 623 — — 623 1,154 (2,517 ) 50,762 492,476 Energy-related 2,186 — — — — 170 2 1,231 3,589 Residential mortgage 365,261 7 940 — 947 1,109 (6,601 ) 140,580 501,296 Consumer - Home equity 381,107 622 416 291 1,329 1,291 (7,333 ) 114,130 490,524 Consumer - Indirect automobile 19 — — — — — — 65 84 Consumer - Credit Card — — — — — — — 582 582 Consumer - Other 74,385 468 127 — 595 206 (2,570 ) 6,292 78,908 Total $ 2,425,267 $ 2,761 $ 2,305 $ 291 $ 5,357 $ 5,421 $ (23,856 ) $ 724,719 $ 3,136,908 (1) Past due and non-accrual information presents acquired loans at the gross loan balance, prior to application of discounts. (2) Past due and non-accrual loan amounts exclude acquired impaired loans, even if contractually past due or if the Company does not expect to receive payment in full, as the Company is currently accreting interest income over the expected life of the loans. Loans Acquired As discussed in Note 3, during 2015, the Company acquired loans with fair values of $0.3 billion from Florida Bank Group, $1.1 billion from Old Florida, and $0.8 billion from Georgia Commerce. Of the total $2.2 billion of loans acquired, $2.1 billion were determined to have no evidence of deteriorated credit quality and are accounted for under ASC Topics 310-10 and 310-20. The remaining $57.8 million were determined to exhibit deteriorated credit quality since origination under ASC 310-30. The tables below show the balances acquired during 2015 for these two subsections of the acquired portfolio as of the acquisition date. (Dollars in thousands) Acquired Non-Impaired Loans Contractually required principal and interest at acquisition $ 2,384,114 Expected losses and foregone interest (15,539 ) Cash flows expected to be collected at acquisition 2,368,575 Fair value of acquired loans at acquisition $ 2,105,466 (Dollars in thousands) Acquired Impaired Loans Contractually required principal and interest at acquisition $ 76,445 Non-accretable difference (expected losses and foregone interest) (11,867 ) Cash flows expected to be collected at acquisition 64,578 Accretable yield (6,823 ) Basis in acquired loans at acquisition $ 57,755 The following is a summary of changes in the accretable difference for all loans accounted for under ASC 310-30 during the years ended December 31: (Dollars in thousands) 2016 2015 2014 Balance at beginning of period $ 227,502 $ 287,651 $ 354,892 Additions — 6,823 13,848 Transfers from non-accretable difference to accretable yield 5,490 9,916 25,844 Accretion (68,211 ) (80,479 ) (103,233 ) Changes in expected cash flows not affecting non-accretable differences (1) 10,273 3,591 (3,700 ) Balance at end of period $ 175,054 $ 227,502 $ 287,651 (1) Includes changes in cash flows expected to be collected due to the impact of changes in actual or expected timing of liquidation events, modifications, changes in interest rates and changes in prepayment assumptions. Troubled Debt Restructurings Information about the Company’s troubled debt restructurings ("TDRs") at December 31, 2016 and 2015 is presented in the following tables. Modifications of loans that are accounted for within a pool under ASC Topic 310-30 are excluded as TDRs. Accordingly, such modifications do not result in the removal of those loans from the pool, even if the modification of those loans would otherwise be considered a TDR. As a result, all such acquired loans that would otherwise meet the criteria for classification as a TDR are excluded from the tables below. TDRs totaling $222.4 million and $57.0 million occurred during the twelve months ended December 31, 2016 and December 31, 2015, respectively, through modification of the original loan terms. There were no TDRs that occurred during the twelve months ended December 31, 2014 through modification of the original loan terms. The following table provides information on how the TDRs were modified during the years ended December 31: (Dollars in thousands) 2016 2015 Extended maturities $ 75,315 $ 15,594 Interest rate adjustment 193 — Maturity and interest rate adjustment 2,470 23,374 Movement to or extension of interest-rate only payments 27,931 241 Forbearance 76,819 122 Other concession(s) (1) 39,708 17,710 Total $ 222,436 $ 57,041 (1) Other concessions may include covenant waivers, forgiveness of principal or interest associated with a customer bankruptcy, or a combination of any of the above concessions. Of the $222.4 million of TDRs occurring during the twelve months ended December 31, 2016, $85.9 million are on accrual status and $136.5 million are on non-accrual status. Of the $57.0 million of TDRs occurring during the twelve months ended December 31, 2015, $34.5 million were on accrual status and $22.5 million are on non-accrual status. The following table presents the end of period balance for loans modified in a TDR during the years ended December 31: 2016 2015 (In thousands, except number of loans) Number of Loans Pre-modification Outstanding Recorded Investment Post-modification Outstanding Recorded Investment Number of Loans Pre-modification Outstanding Recorded Investment Post-modification Outstanding Recorded Investment Commercial real estate 44 $ 30,844 $ 24,997 11 $ 26,764 $ 25,250 Commercial and industrial 59 36,379 34,415 26 21,233 18,114 Energy-related 24 133,933 141,848 2 9,797 9,484 Residential mortgage 43 5,141 4,946 1 70 68 Consumer - Home equity 158 13,273 12,568 50 4,440 3,865 Consumer - Indirect 79 983 792 6 79 79 Consumer - Other 116 3,087 2,870 17 248 181 Total 523 $ 223,640 $ 222,436 113 $ 62,631 $ 57,041 Information detailing TDRs that defaulted during the years ended December 31, 2016 and 2015 and were modified in the previous twelve months (i.e., the twelve months prior to the default) is presented in the following table. The Company has defined a default as any loan with a loan payment that is currently past due greater than 30 days , or was past due greater than 30 days at any point during the previous twelve months, or since the date of modification, whichever is shorter. December 31, 2016 December 31, 2015 (In thousands, except number of loans) Number of Loans Recorded Investment Number of Loans Recorded Investment Commercial real estate 9 $ 467 6 $ 22,075 Commercial and industrial 21 12,996 20 8,970 Energy-related 2 5,034 1 3,120 Residential mortgage 8 405 — — Consumer - Home Equity 25 1,379 20 1,547 Consumer - Indirect automobile 37 338 6 79 Consumer - Other 22 606 9 2 Total 124 $ 21,225 62 $ 35,793" id="sjs-B4">LOANS Loans consist of the following, segregated into legacy and acquired loans, for the periods indicated: December 31, 2016 (Dollars in thousands) Legacy Loans Acquired Loans Total Commercial loans: Real estate $ 5,623,314 $ 1,178,952 $ 6,802,266 Commercial and industrial 3,194,796 348,326 3,543,122 Energy-related 559,289 1,904 561,193 9,377,399 1,529,182 10,906,581 Residential mortgage loans: 854,216 413,184 1,267,400 Consumer and other loans: Home equity 1,783,421 372,505 2,155,926 Indirect automobile 131,048 4 131,052 Other 548,840 55,172 604,012 2,463,309 427,681 2,890,990 Total $ 12,694,924 $ 2,370,047 $ 15,064,971 December 31, 2015 (Dollars in thousands) Legacy Loans Acquired Loans Total Commercial loans: Real estate $ 4,504,062 $ 1,569,449 $ 6,073,511 Commercial and industrial 2,952,102 492,476 3,444,578 Energy-related 677,177 3,589 680,766 8,133,341 2,065,514 10,198,855 Residential mortgage loans: 694,023 501,296 1,195,319 Consumer and other loans: Home equity 1,575,643 490,524 2,066,167 Indirect automobile 246,214 84 246,298 Other 541,299 79,490 620,789 2,363,156 570,098 2,933,254 Total $ 11,190,520 $ 3,136,908 $ 14,327,428 Between 2009 and 2011, the Company acquired certain assets and liabilities of six failed banks. Substantially all of the loans and foreclosed real estate that were acquired through these transactions were covered by loss share agreements between the FDIC and IBERIABANK, as well as FDIC loss share agreements assumed in connection with the Company's acquisition of Georgia Commerce in 2015, which afforded IBERIABANK loss protection. In December of 2016, the Company terminated all loss share agreements associated with FDIC-assisted acquisitions. Covered loans, which are included in the December 31, 2015 acquired loans table above, were $229.2 million at December 31, 2015 of which $191.7 million were residential mortgage and home equity loans. As a result of the termination of the loss share agreements, there were no covered loans outstanding as of December 31, 2016. Refer to Note 7 for additional information regarding the Company’s termination of its loss share agreements. Net deferred loan origination fees were $22.6 million and $18.7 million at December 31, 2016 and 2015, respectively. In addition to loans issued in the normal course of business, the Company considers overdrafts on customer deposit accounts to be loans and reclassifies these overdrafts as loans in its consolidated balance sheets. At December 31, 2016 and 2015, overdrafts of $4.2 million and $5.1 million , respectively, have been reclassified to loans. Loans with carrying values of $4.5 billion and $3.9 billion were pledged as collateral for borrowings at December 31, 2016 and 2015, respectively. Aging Analysis The following tables provide an analysis of the aging of loans as of December 31, 2016 and 2015. Due to the difference in accounting for acquired loans, the tables below further segregate the Company’s loans between loans originated, or renewed and underwritten by the Company ("legacy loans") and acquired loans. December 31, 2016 Legacy loans Accruing (Dollars in thousands) Current or less than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Total Loans Commercial real estate - Construction $ 740,761 $ — $ — $ — $ — $ — $ 740,761 Commercial real estate - Other 4,863,902 1,861 351 — 2,212 16,439 4,882,553 Commercial and industrial 3,158,700 3,999 870 — 4,869 31,227 3,194,796 Energy-related 407,434 — 1,526 — 1,526 150,329 559,289 Residential mortgage 836,509 2,012 1,577 1,104 4,693 13,014 854,216 Consumer - Home equity 1,768,763 5,249 1,430 — 6,679 7,979 1,783,421 Consumer - Indirect automobile 127,054 2,551 405 — 2,956 1,038 131,048 Consumer - Credit card 81,602 199 99 — 298 624 82,524 Consumer - Other 462,650 2,155 618 — 2,773 893 466,316 Total $ 12,447,375 $ 18,026 $ 6,876 $ 1,104 $ 26,006 $ 221,543 $ 12,694,924 December 31, 2015 Legacy loans Accruing (Dollars in thousands) Current or less than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Total Loans Commercial real estate - Construction $ 635,560 $ 801 $ — $ — $ 801 $ 120 $ 636,481 Commercial real estate - Other 3,848,584 2,687 793 95 3,575 15,422 3,867,581 Commercial and industrial 2,943,409 1,208 739 87 2,034 6,659 2,952,102 Energy-related 670,081 15 — — 15 7,081 677,177 Residential mortgage 676,347 1,075 2,485 442 4,002 13,674 694,023 Consumer - Home equity 1,565,596 3,549 870 — 4,419 5,628 1,575,643 Consumer - Indirect automobile 242,328 2,187 518 — 2,705 1,181 246,214 Consumer - Credit card 76,360 394 113 — 507 394 77,261 Consumer - Other 460,594 1,923 752 — 2,675 769 464,038 Total $ 11,118,859 $ 13,839 $ 6,270 $ 624 $ 20,733 $ 50,928 $ 11,190,520 December 31, 2016 Acquired loans (1) (2) Accruing (Dollars in thousands) Current or Less Than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Discount/Premium Acquired Impaired Loans Total Loans Commercial real estate - Construction $ 26,714 $ — $ — $ — $ — $ 1,946 $ (243 ) $ 32,991 $ 61,408 Commercial real estate - Other 871,492 716 55 32 803 1,221 (3,649 ) 247,677 1,117,544 Commercial and industrial 314,990 73 51 — 124 1,317 (837 ) 32,732 348,326 Energy-related 1,910 — — — — — (6 ) — 1,904 Residential mortgage 290,031 328 989 — 1,317 719 (1,835 ) 122,952 413,184 Consumer - Home equity 286,411 1,078 189 250 1,517 1,395 (5,237 ) 88,419 372,505 Consumer - Indirect automobile — — — — — — — 4 4 Consumer - Credit Card 468 — — — — — — — 468 Consumer - Other 49,449 391 97 — 488 360 (1,004 ) 5,411 54,704 Total $ 1,841,465 $ 2,586 $ 1,381 $ 282 $ 4,249 $ 6,958 $ (12,811 ) $ 530,186 $ 2,370,047 December 31, 2015 Acquired loans (1) (2) Accruing (Dollars in thousands) Current or Less Than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Discount/Premium Acquired Impaired Loans Total Loans Commercial real estate - Construction $ 69,167 $ 180 $ 117 $ — $ 297 $ — $ (358 ) $ 56,320 $ 125,426 Commercial real estate - Other 1,090,688 861 705 — 1,566 1,491 (4,479 ) 354,757 1,444,023 Commercial and industrial 442,454 623 — — 623 1,154 (2,517 ) 50,762 492,476 Energy-related 2,186 — — — — 170 2 1,231 3,589 Residential mortgage 365,261 7 940 — 947 1,109 (6,601 ) 140,580 501,296 Consumer - Home equity 381,107 622 416 291 1,329 1,291 (7,333 ) 114,130 490,524 Consumer - Indirect automobile 19 — — — — — — 65 84 Consumer - Credit Card — — — — — — — 582 582 Consumer - Other 74,385 468 127 — 595 206 (2,570 ) 6,292 78,908 Total $ 2,425,267 $ 2,761 $ 2,305 $ 291 $ 5,357 $ 5,421 $ (23,856 ) $ 724,719 $ 3,136,908 (1) Past due and non-accrual information presents acquired loans at the gross loan balance, prior to application of discounts. (2) Past due and non-accrual loan amounts exclude acquired impaired loans, even if contractually past due or if the Company does not expect to receive payment in full, as the Company is currently accreting interest income over the expected life of the loans. Loans Acquired As discussed in Note 3, during 2015, the Company acquired loans with fair values of $0.3 billion from Florida Bank Group, $1.1 billion from Old Florida, and $0.8 billion from Georgia Commerce. Of the total $2.2 billion of loans acquired, $2.1 billion were determined to have no evidence of deteriorated credit quality and are accounted for under ASC Topics 310-10 and 310-20. The remaining $57.8 million were determined to exhibit deteriorated credit quality since origination under ASC 310-30. The tables below show the balances acquired during 2015 for these two subsections of the acquired portfolio as of the acquisition date. (Dollars in thousands) Acquired Non-Impaired Loans Contractually required principal and interest at acquisition $ 2,384,114 Expected losses and foregone interest (15,539 ) Cash flows expected to be collected at acquisition 2,368,575 Fair value of acquired loans at acquisition $ 2,105,466 (Dollars in thousands) Acquired Impaired Loans Contractually required principal and interest at acquisition $ 76,445 Non-accretable difference (expected losses and foregone interest) (11,867 ) Cash flows expected to be collected at acquisition 64,578 Accretable yield (6,823 ) Basis in acquired loans at acquisition $ 57,755 The following is a summary of changes in the accretable difference for all loans accounted for under ASC 310-30 during the years ended December 31: (Dollars in thousands) 2016 2015 2014 Balance at beginning of period $ 227,502 $ 287,651 $ 354,892 Additions — 6,823 13,848 Transfers from non-accretable difference to accretable yield 5,490 9,916 25,844 Accretion (68,211 ) (80,479 ) (103,233 ) Changes in expected cash flows not affecting non-accretable differences (1) 10,273 3,591 (3,700 ) Balance at end of period $ 175,054 $ 227,502 $ 287,651 (1) Includes changes in cash flows expected to be collected due to the impact of changes in actual or expected timing of liquidation events, modifications, changes in interest rates and changes in prepayment assumptions. Troubled Debt Restructurings Information about the Company’s troubled debt restructurings ("TDRs") at December 31, 2016 and 2015 is presented in the following tables. Modifications of loans that are accounted for within a pool under ASC Topic 310-30 are excluded as TDRs. Accordingly, such modifications do not result in the removal of those loans from the pool, even if the modification of those loans would otherwise be considered a TDR. As a result, all such acquired loans that would otherwise meet the criteria for classification as a TDR are excluded from the tables below. TDRs totaling $222.4 million and $57.0 million occurred during the twelve months ended December 31, 2016 and December 31, 2015, respectively, through modification of the original loan terms. There were no TDRs that occurred during the twelve months ended December 31, 2014 through modification of the original loan terms. The following table provides information on how the TDRs were modified during the years ended December 31: (Dollars in thousands) 2016 2015 Extended maturities $ 75,315 $ 15,594 Interest rate adjustment 193 — Maturity and interest rate adjustment 2,470 23,374 Movement to or extension of interest-rate only payments 27,931 241 Forbearance 76,819 122 Other concession(s) (1) 39,708 17,710 Total $ 222,436 $ 57,041 (1) Other concessions may include covenant waivers, forgiveness of principal or interest associated with a customer bankruptcy, or a combination of any of the above concessions. Of the $222.4 million of TDRs occurring during the twelve months ended December 31, 2016, $85.9 million are on accrual status and $136.5 million are on non-accrual status. Of the $57.0 million of TDRs occurring during the twelve months ended December 31, 2015, $34.5 million were on accrual status and $22.5 million are on non-accrual status. The following table presents the end of period balance for loans modified in a TDR during the years ended December 31: 2016 2015 (In thousands, except number of loans) Number of Loans Pre-modification Outstanding Recorded Investment Post-modification Outstanding Recorded Investment Number of Loans Pre-modification Outstanding Recorded Investment Post-modification Outstanding Recorded Investment Commercial real estate 44 $ 30,844 $ 24,997 11 $ 26,764 $ 25,250 Commercial and industrial 59 36,379 34,415 26 21,233 18,114 Energy-related 24 133,933 141,848 2 9,797 9,484 Residential mortgage 43 5,141 4,946 1 70 68 Consumer - Home equity 158 13,273 12,568 50 4,440 3,865 Consumer - Indirect 79 983 792 6 79 79 Consumer - Other 116 3,087 2,870 17 248 181 Total 523 $ 223,640 $ 222,436 113 $ 62,631 $ 57,041 Information detailing TDRs that defaulted during the years ended December 31, 2016 and 2015 and were modified in the previous twelve months (i.e., the twelve months prior to the default) is presented in the following table. The Company has defined a default as any loan with a loan payment that is currently past due greater than 30 days , or was past due greater than 30 days at any point during the previous twelve months, or since the date of modification, whichever is shorter. December 31, 2016 December 31, 2015 (In thousands, except number of loans) Number of Loans Recorded Investment Number of Loans Recorded Investment Commercial real estate 9 $ 467 6 $ 22,075 Commercial and industrial 21 12,996 20 8,970 Energy-related 2 5,034 1 3,120 Residential mortgage 8 405 — — Consumer - Home Equity 25 1,379 20 1,547 Consumer - Indirect automobile 37 338 6 79 Consumer - Other 22 606 9 2 Total 124 $ 21,225 62 $ 35,793

Allowance for Credit Losses and

Allowance for Credit Losses and Credit Quality	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Allowance for Credit Losses and Credit Quality	ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY Allowance for Credit Losses Activity A summary of changes in the allowance for credit losses for the years ended December 31 is as follows: 2016 (Dollars in thousands) Legacy Loans Acquired Loans Total Allowance for credit losses Allowance for loan losses at beginning of period $ 93,808 $ 44,570 $ 138,378 Provision for (Reversal of) loan losses before benefit attributable to FDIC loss share agreements 44,791 (1,864 ) 42,927 Adjustment attributable to FDIC loss share arrangements — 1,497 1,497 Net provision for loan losses 44,791 (367 ) 44,424 Adjustment attributable to FDIC loss share arrangements — (1,497 ) (1,497 ) Transfer of balance to OREO and other (9 ) (2,772 ) (2,781 ) Loans charged-off (38,055 ) (1,784 ) (39,839 ) Recoveries 5,034 1,000 6,034 Allowance for loan losses at end of period $ 105,569 $ 39,150 $ 144,719 Reserve for unfunded commitments at beginning of period $ 14,145 $ — $ 14,145 Provision for (Reversal of) unfunded lending commitments (2,904 ) — (2,904 ) Reserve for unfunded commitments at end of period $ 11,241 $ — $ 11,241 Allowance for credit losses at end of period $ 116,810 $ 39,150 $ 155,960 2015 Legacy Loans Acquired Loans Total Allowance for credit losses Allowance for loan losses at beginning of period $ 76,174 $ 53,957 $ 130,131 Provision for loan losses before benefit attributable to FDIC loss share agreements 27,711 1,837 29,548 Adjustment attributable to FDIC loss share arrangements — 1,360 1,360 Net provision for loan losses 27,711 3,197 30,908 Adjustment attributable to FDIC loss share arrangements — (1,360 ) (1,360 ) Transfer of balance to OREO and other — (10,419 ) (10,419 ) Loans charged-off (15,778 ) (1,523 ) (17,301 ) Recoveries 5,701 718 6,419 Allowance for loan losses at end of period $ 93,808 $ 44,570 $ 138,378 Reserve for unfunded commitments at beginning of period $ 11,801 $ — $ 11,801 Provision for unfunded lending commitments 2,344 — 2,344 Reserve for unfunded commitments at end of period $ 14,145 $ — $ 14,145 Allowance for credit losses at end of period $ 107,953 $ 44,570 $ 152,523 2014 Legacy Loans Acquired Loans Total Allowance for credit losses Allowance for loan losses at beginning of period $ 67,342 $ 75,732 $ 143,074 Provision for loan losses before benefit attributable to FDIC loss share agreements 14,274 526 14,800 Adjustment attributable to FDIC loss share arrangements — 4,260 4,260 Net provision for loan losses $ 14,274 $ 4,786 $ 19,060 Adjustment attributable to FDIC loss share arrangements $ — $ (4,260 ) $ (4,260 ) Transfer of balance to OREO and other — (22,157 ) (22,157 ) Loans charged-off (11,312 ) (671 ) (11,983 ) Recoveries 5,870 527 6,397 Allowance for loan losses at end of period $ 76,174 $ 53,957 $ 130,131 Reserve for unfunded commitments at beginning of period $ 11,147 $ — $ 11,147 Provision for unfunded lending commitments 654 — 654 Reserve for unfunded commitments at end of period $ 11,801 $ — $ 11,801 Allowance for credit losses at end of period $ 87,975 $ 53,957 $ 141,932 A summary of changes in the allowance for credit losses for legacy loans, by loan portfolio type, for the years ended December 31 is as follows: 2016 (Dollars in thousands) Commercial Real Estate Commercial and Industrial Energy-related Residential Mortgage Consumer Total Allowance for loan losses at beginning of period $ 24,658 $ 23,283 $ 23,863 $ 3,947 $ 18,057 $ 93,808 Provision for (Reversal of) loan losses 4,042 15,476 14,776 64 10,433 44,791 Transfer of balance to OREO and other — — — (9 ) — (9 ) Loans charged off (4,316 ) (3,720 ) (16,993 ) (313 ) (12,713 ) (38,055 ) Recoveries 1,024 395 840 146 2,629 5,034 Allowance for loan losses at end of period $ 25,408 $ 35,434 $ 22,486 $ 3,835 $ 18,406 $ 105,569 Reserve for unfunded commitments at beginning of period $ 4,160 $ 3,448 $ 2,665 $ 830 $ 3,042 $ 14,145 Provision for (Reversal of) unfunded commitments (954 ) 87 (1,662 ) (173 ) (202 ) (2,904 ) Reserve for unfunded commitments at end of period $ 3,206 $ 3,535 $ 1,003 $ 657 $ 2,840 $ 11,241 Allowance on loans individually evaluated for impairment $ 641 $ 10,864 $ 9,769 $ 144 $ 1,358 $ 22,776 Allowance on loans collectively evaluated for impairment 24,767 24,570 12,717 3,691 17,048 82,793 Loans, net of unearned income: Balance at end of period $ 5,623,314 $ 3,194,796 $ 559,289 $ 854,216 $ 2,463,309 $ 12,694,924 Balance at end of period individually evaluated for impairment 34,031 41,518 196,327 4,312 16,457 292,645 Balance at end of period collectively evaluated for impairment 5,589,283 3,153,278 $ 362,962 849,904 2,446,852 12,402,279 2015 (Dollars in thousands) Commercial Real Estate Commercial and Industrial Energy-related Residential Mortgage Consumer Total Allowance for loan losses at beginning of period $ 26,752 $ 24,455 $ 5,949 $ 2,678 $ 16,340 $ 76,174 Provision for (Reversal of) loan losses (1,466 ) (103 ) 17,917 1,493 9,870 27,711 Loans charged off (2,525 ) (1,276 ) (3 ) (291 ) (11,683 ) (15,778 ) Recoveries 1,897 207 — 67 3,530 5,701 Allowance for loan losses at end of period $ 24,658 $ 23,283 $ 23,863 $ 3,947 $ 18,057 $ 93,808 Reserve for unfunded commitments at beginning of period $ 3,370 $ 3,733 $ 1,596 $ 168 $ 2,934 $ 11,801 Provision for (Reversal of) unfunded commitments 790 (285 ) 1,069 662 108 2,344 Reserve for unfunded commitments at end of period $ 4,160 $ 3,448 $ 2,665 $ 830 $ 3,042 $ 14,145 Allowance on loans individually evaluated for impairment $ 1,246 $ 272 $ 2,122 $ 1 $ 352 $ 3,993 Allowance on loans collectively evaluated for impairment 23,412 23,011 21,741 3,946 17,705 89,815 Loans, net of unearned income: Balance at end of period $ 4,504,062 $ 2,952,102 $ 677,177 $ 694,023 $ 2,363,156 $ 11,190,520 Balance at end of period individually evaluated for impairment 28,857 20,086 13,020 70 4,608 66,641 Balance at end of period collectively evaluated for impairment 4,475,205 2,932,016 $ 664,157 693,953 2,358,548 11,123,879 2014 (Dollars in thousands) Commercial Real Estate Commercial and Industrial Energy-related Residential Mortgage Consumer Total Allowance for loan losses at beginning of period $ 22,872 $ 20,839 $ 6,878 $ 2,546 $ 14,207 $ 67,342 Provision for (Reversal of) loan losses 2,171 4,971 (929 ) 566 7,495 14,274 Loans charged off (1,164 ) (1,400 ) — (578 ) (8,170 ) (11,312 ) Recoveries 2,873 45 — 144 2,808 5,870 Allowance for loan losses at end of period $ 26,752 $ 24,455 $ 5,949 $ 2,678 $ 16,340 $ 76,174 Reserve for unfunded commitments at beginning of period $ 3,071 $ 1,814 $ 3,043 $ 72 $ 3,147 $ 11,147 Provision for (Reversal of) unfunded commitments 299 1,919 (1,447 ) 96 (213 ) 654 Reserve for unfunded commitments at end of period $ 3,370 $ 3,733 $ 1,596 $ 168 $ 2,934 $ 11,801 Allowance on loans individually evaluated for impairment $ 20 $ 407 $ — $ — $ 3 $ 430 Allowance on loans collectively evaluated for impairment 26,732 24,048 5,949 2,678 16,337 75,744 Loans, net of unearned income: Balance at end of period $ 3,676,811 $ 2,452,521 $ 872,866 $ 527,694 $ 2,138,822 $ 9,668,714 Balance at end of period individually evaluated for impairment 7,036 3,965 — — 699 11,700 Balance at end of period collectively evaluated for impairment 3,669,775 2,448,556 872,866 527,694 2,138,123 9,657,014 A summary of changes in the allowance for loan losses for acquired loans, by loan portfolio type, for the years ended December 31 is as follows: 2016 (Dollars in thousands) Commercial Commercial Energy-related Residential Consumer Total Allowance for loan losses at beginning of period $ 25,979 $ 2,819 $ 125 $ 7,841 $ 7,806 $ 44,570 Provision for (Reversal of) loan losses (1,598 ) 1,645 (86 ) 759 (1,087 ) (367 ) Decrease in FDIC loss share receivable (34 ) (50 ) — (1,090 ) (323 ) (1,497 ) Transfer of balance to OREO and other (868 ) (519 ) — (132 ) (1,253 ) (2,772 ) Loans charged off (22 ) (932 ) — — (830 ) (1,784 ) Recoveries 117 267 — 34 582 1,000 Allowance for loan losses at end of period $ 23,574 $ 3,230 $ 39 $ 7,412 $ 4,895 $ 39,150 Allowance on loans individually evaluated for impairment $ 737 $ 780 $ — $ — $ — $ 1,517 Allowance on loans collectively evaluated for impairment 22,837 2,450 39 7,412 4,895 37,633 Loans, net of unearned income: Balance at end of period $ 1,178,952 $ 348,326 $ 1,904 $ 413,184 $ 427,681 $ 2,370,047 Balance at end of period individually evaluated for impairment 8,246 1,879 — — 10 10,135 Balance at end of period collectively evaluated for impairment 890,038 313,715 1,904 290,232 333,837 1,829,726 Balance at end of period acquired with deteriorated credit quality 280,668 32,732 — 122,952 93,834 530,186 2015 (Dollars in thousands) Commercial Commercial Energy-related Residential Consumer Total Allowance for loan losses at beginning of period $ 29,949 $ 3,265 $ 51 $ 6,484 $ 14,208 $ 53,957 Provision for (Reversal of) loan losses 2,182 (122 ) 74 2,126 (1,063 ) 3,197 Increase (Decrease) in FDIC loss share receivable 757 (49 ) — (235 ) (1,833 ) (1,360 ) Transfer of balance to OREO and other (6,849 ) (275 ) — (491 ) (2,804 ) (10,419 ) Loans charged off (281 ) — — (71 ) (1,171 ) (1,523 ) Recoveries 221 — — 28 469 718 Allowance for loan losses at end of period $ 25,979 $ 2,819 $ 125 $ 7,841 $ 7,806 $ 44,570 Allowance on loans individually evaluated for impairment $ — $ 41 $ — $ — $ 45 $ 86 Allowance on loans collectively evaluated for impairment 25,979 2,778 125 7,841 7,761 44,484 Loans, net of unearned income: Balance at end of period $ 1,569,449 $ 492,476 $ 3,589 $ 501,296 $ 570,098 $ 3,136,908 Balance at end of period individually evaluated for impairment 720 164 — — 458 1,342 Balance at end of period collectively evaluated for impairment 1,157,652 441,550 2,358 360,716 448,571 2,410,847 Balance at end of period acquired with deteriorated credit quality 411,077 50,762 1,231 140,580 121,069 724,719 2014 (Dollars in thousands) Commercial Commercial Energy-related Residential Consumer Total Allowance for loan losses at beginning of period $ 42,026 $ 6,641 $ — $ 10,889 $ 16,176 $ 75,732 Provision for loan losses 665 536 51 1,296 2,238 4,786 Increase (Decrease) in FDIC loss share receivable 227 509 — (3,854 ) (1,142 ) (4,260 ) Transfer of balance to OREO and other (13,117 ) (4,421 ) — (1,914 ) (2,705 ) (22,157 ) Loans charged off — — — (35 ) (636 ) (671 ) Recoveries 148 — — 102 277 527 Allowance for loan losses at end of period $ 29,949 $ 3,265 $ 51 $ 6,484 $ 14,208 $ 53,957 Allowance on loans individually evaluated for impairment $ — $ — $ — $ — $ — $ — Allowance on loans collectively evaluated for impairment 29,949 3,265 51 6,484 14,208 53,957 Loans, net of unearned income: Balance at end of period $ 684,968 $ 119,174 $ 7,742 $ 552,603 $ 407,843 $ 1,772,330 Balance at end of period individually evaluated for impairment — — — — — — Balance at end of period collectively evaluated for impairment 169,338 60,584 7,742 402,347 265,168 905,179 Balance at end of period acquired with deteriorated credit quality 515,630 58,590 — 150,256 142,675 867,151 Portfolio Segment Risk Factors Commercial real estate loans include loans to commercial customers for long-term financing of land and buildings or for land development or construction of a building. These loans are repaid through revenues from operations of the businesses, rents of properties, sales of properties and refinances. Commercial and industrial loans represent loans to commercial customers to finance general working capital needs, equipment purchases and other projects where repayment is derived from cash flows resulting from business operations. The Company originates commercial business loans on a secured and, to a lesser extent, unsecured basis. Residential mortgage loans consist of loans to consumers to finance a primary residence. The vast majority of the residential mortgage loan portfolio is comprised of non-conforming 1-4 family mortgage loans secured by properties located in the Company's market areas and originated under terms and documentation that permit their sale in a secondary market. Consumer loans are offered by the Company in order to provide a full range of retail financial services to its customers and include home equity, credit card and other direct consumer installment loans. The Company originates substantially all of its consumer loans in its primary market areas. Loans in the consumer segment are sensitive to unemployment and other key consumer economic measures. Credit Quality The Company utilizes an asset risk classification system in accordance with guidelines established by the Federal Reserve Board as part of its efforts to monitor commercial asset quality. “Special mention” loans are defined as loans where known information about possible credit problems of the borrower cause management to have some doubt as to the ability of these borrowers to comply with the present loan repayment terms and which may result in future disclosure of these loans as non-performing. For assets with identified credit issues, the Company has two primary classifications for problem assets: “substandard” and “doubtful.” Substandard assets have one or more defined weaknesses and are characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected. Doubtful assets have the weaknesses of substandard assets with the additional characteristic that the weaknesses make collection or liquidation in full satisfaction of the loan balance outstanding questionable, which makes probability of loss based on currently existing facts, conditions, and values higher. Loans classified as “Pass” do not meet the criteria set forth for special mention, substandard, or doubtful classification and are not considered criticized. Asset risk classifications are determined at origination or acquisition and reviewed on an ongoing basis. Risk classifications are changed if, in the opinion of management, the risk profile of the customer has changed since the last review of the loan relationship. The Company’s investment in loans by credit quality indicator is presented in the following tables. The tables below further segregate the Company’s loans between loans that were originated by the Company (legacy loans) and acquired loans. Loan premiums/discounts in the tables below represent the adjustment of acquired loans to fair value at the acquisition date, as adjusted for income accretion and changes in cash flow estimates in subsequent periods. Asset risk classifications for commercial loans reflect the classification as of December 31, 2016 and 2015, respectively. Credit quality information in the tables below includes total loans acquired (including acquired impaired loans) at the gross loan balance, prior to the application of premiums/discounts, at December 31, 2016 and 2015. Loan delinquency is the primary credit quality indicator that the Company utilizes to monitor consumer asset quality. Legacy loans December 31, 2016 December 31, 2015 (Dollars in thousands) Pass Special Mention Sub- Doubtful Total Pass Special Mention Sub- Doubtful Total Commercial real estate - Construction $ 734,687 $ 2,203 $ 3,871 $ — $ 740,761 $ 634,889 $ 160 $ 1,432 $ — $ 636,481 Commercial real estate - Other 4,801,494 26,159 54,900 — 4,882,553 3,806,528 21,877 37,001 2,175 3,867,581 Commercial and industrial 3,112,300 29,763 35,199 17,534 3,194,796 2,911,396 14,826 19,888 5,992 2,952,102 Energy-related 242,123 80,084 225,724 11,358 559,289 531,657 67,937 74,272 3,311 677,177 Total $ 8,890,604 $ 138,209 $ 319,694 $ 28,892 $ 9,377,399 $ 7,884,470 $ 104,800 $ 132,593 $ 11,478 $ 8,133,341 Legacy loans December 31, 2016 December 31, 2015 (Dollars in thousands) Current 30+ Days Past Due Total Current 30+ Days Past Due Total Residential mortgage $ 836,509 $ 17,707 $ 854,216 $ 676,347 $ 17,676 $ 694,023 Consumer - Home equity 1,768,763 14,658 1,783,421 1,565,596 10,047 1,575,643 Consumer - Indirect automobile 127,054 3,994 131,048 242,328 3,886 246,214 Consumer - Credit card 81,602 922 82,524 76,360 901 77,261 Consumer - Other 462,650 3,666 466,316 460,594 3,444 464,038 Total $ 3,276,578 $ 40,947 $ 3,317,525 $ 3,021,225 $ 35,954 $ 3,057,179 Acquired loans December 31, 2016 December 31, 2015 (Dollars in thousands) Pass Special Sub-standard Doubtful Loss Premium/(Discount) Total Pass Special Sub-standard Doubtful Loss Premium/(Discount) Total Commercial real estate - Construction $ 46,498 $ 459 $ 3,118 $ 2,574 $ — $ 8,759 $ 61,408 $ 104,064 $ 1,681 $ 8,803 $ 771 $ — $ 10,107 $ 125,426 Commercial real 1,090,063 19,284 49,136 1,457 23 (42,419 ) 1,117,544 1,395,884 26,080 79,119 6,124 111 (63,295 ) 1,444,023 Commercial and industrial 323,154 1,416 27,749 494 — (4,487 ) 348,326 473,241 8,376 16,510 1,206 43 (6,900 ) 492,476 Energy-related 1,910 — — — — (6 ) 1,904 2,166 55 170 1,198 — — 3,589 Total $ 1,461,625 $ 21,159 $ 80,003 $ 4,525 $ 23 $ (38,153 ) $ 1,529,182 $ 1,975,355 $ 36,192 $ 104,602 $ 9,299 $ 154 $ (60,088 ) $ 2,065,514 Acquired loans December 31, 2016 December 31, 2015 (Dollars in thousands) Current 30+ Days Past Due Premium (Discount) Total Current 30+ Days Past Due Premium (Discount) Total Residential mortgage $ 424,300 $ 20,914 $ (32,030 ) $ 413,184 $ 506,103 $ 24,752 $ (29,559 ) $ 501,296 Consumer - Home equity 377,021 12,807 (17,323 ) 372,505 503,635 16,381 (29,492 ) 490,524 Consumer - Indirect automobile 12 — (8 ) 4 72 12 — 84 Consumer - Other 58,141 1,423 (4,392 ) 55,172 79,732 1,475 (1,717 ) 79,490 Total $ 859,474 $ 35,144 $ (53,753 ) $ 840,865 $ 1,089,542 $ 42,620 $ (60,768 ) $ 1,071,394 Legacy Impaired Loans Information on the Company’s investment in legacy impaired loans, which include all TDRs and all other non-accrual loans evaluated or measured individually for impairment purposes of determining the allowance for loan losses, is presented in the following tables as of and for the periods indicated. December 31, 2016 (Dollars in thousands) Unpaid Principal Balance Recorded Investment Related Average Interest With no related allowance recorded: Commercial real estate $ 17,299 $ 16,507 $ — $ 21,133 $ 948 Commercial and industrial 14,202 13,189 — 15,492 805 Energy-related 152,424 143,239 — 114,623 2,903 Consumer - Home equity — — — — — Consumer - Other — — — — — With an allowance recorded: Commercial real estate 17,688 17,524 (641 ) 16,771 494 Commercial and industrial 28,829 28,329 (10,864 ) 29,333 1,107 Energy-related 53,967 53,088 (9,769 ) 47,469 1,677 Residential mortgage 4,627 4,312 (144 ) 4,377 161 Consumer - Home equity 13,906 13,257 (993 ) 10,227 434 Consumer - Indirect automobile 1,037 758 (114 ) 956 49 Consumer - Other 2,447 2,442 (251 ) 1,469 102 Total $ 306,426 $ 292,645 $ (22,776 ) $ 261,850 $ 8,680 Total commercial loans $ 284,409 $ 271,876 $ (21,274 ) $ 244,821 $ 7,934 Total mortgage loans 4,627 4,312 (144 ) 4,377 161 Total consumer loans 17,390 16,457 (1,358 ) 12,652 585 December 31, 2015 (Dollars in thousands) Unpaid Principal Balance Recorded Investment Related Average Interest With no related allowance recorded: Commercial real estate $ 17,002 $ 16,145 $ — $ 15,864 $ 315 Commercial and industrial 14,571 14,340 — 18,839 1,148 Energy-related — — — — — Consumer - Home equity 730 730 — 533 22 Consumer - Other 66 66 — 66 5 With an allowance recorded: Commercial real estate 12,765 12,712 (1,246 ) 12,985 530 Commercial and industrial 5,748 5,746 (272 ) 5,975 313 Energy-related 13,046 13,020 (2,122 ) 13,899 454 Residential mortgage 70 70 (1 ) 70 5 Consumer - Home equity 3,859 3,683 (337 ) 2,453 73 Consumer - Other 130 129 (15 ) 30 3 Total $ 67,987 $ 66,641 $ (3,993 ) $ 70,714 $ 2,868 Total commercial loans $ 63,132 $ 61,963 $ (3,640 ) $ 67,562 $ 2,760 Total mortgage loans 70 70 (1 ) 70 5 Total consumer loans 4,785 4,608 (352 ) 3,082 103 December 31, 2014 (Dollars in thousands) Unpaid Principal Balance Recorded Investment Related Average Interest With no related allowance recorded: Commercial real estate $ 7,615 $ 6,680 $ — $ 6,703 $ 132 Commercial and industrial 3,710 2,483 — 2,602 39 Consumer - Home equity 748 682 — 696 19 With an allowance recorded: Commercial real estate 356 356 (20 ) 378 23 Commercial and industrial 1,590 1,482 (407 ) 1,849 24 Consumer - Other 17 17 (3 ) 18 2 Total $ 14,036 $ 11,700 $ (430 ) $ 12,246 $ 239 Total commercial loans $ 13,271 $ 11,001 $ (427 ) $ 11,532 $ 218 Total mortgage loans — — — — — Total consumer loans 765 699 (3 ) 714 21 As of December 31, 2016 and 2015, the Company was not committed to lend a material amount of additional funds to any customer whose loan was classified as impaired or as a troubled debt restructuring.

Loss Sharing Agreements and FDI

Loss Sharing Agreements and FDIC Loss Share Receivable	12 Months Ended
	Dec. 31, 2016
Loss Sharing Agreements and FDIC Loss Share Receivable [Abstract]
Loss Sharing Agreements and FDIC Loss Share Receivable	LOSS SHARING AGREEMENTS AND FDIC LOSS SHARE RECEIVABLE In conjunction with the acquisitions of certain assets and liabilities of six failed banks between 2009 and 2011, as well as the acquisition of Georgia Commerce in 2015, the Company entered into or assumed arrangements with the FDIC that obligated the FDIC to reimburse the Company for losses on certain loans associated with the FDIC-assisted transactions. The indemnification assets were recorded at fair value as of the acquisition dates based on estimated cash flows to be received over the expected life of the acquired assets, not to exceed the term of the indemnification agreements. Effective as of December 20, 2016, the Company entered into an agreement with the FDIC to terminate the Company’s loss share agreements ahead of their contractual maturities. Under the terms of the agreement, all rights and obligations of the Company and the FDIC have been resolved and completed. The Company received a net payment of $6.5 million from the FDIC as consideration for termination of the loss share agreements and subsequently derecognized the remaining FDIC indemnification asset and associated assets and liabilities, resulting in a pre-tax loss of $17.8 million . The Company will benefit from all future recoveries, and be responsible for all future losses and expenses related to the assets previously subject to the loss share agreements. The following is a summary of the year-to-date activity for the FDIC loss share receivables: December 31 (Dollars in thousands) 2016 2015 Balance at beginning of period $ 39,878 $ 69,627 Reversal of loan loss provision recorded on FDIC covered loans (1,497 ) (1,360 ) Amortization (16,024 ) (23,500 ) Submission of reimbursable losses to the FDIC (1,945 ) (2,444 ) Impairment (20,402 ) — Changes due to a change in cash flow assumptions on OREO and other changes (10 ) (2,445 ) Balance at end of period $ — $ 39,878

Transfers and Servicing of Fina

Transfers and Servicing of Financial Assets (Including Mortgage Banking Activity)	12 Months Ended
	Dec. 31, 2016
Transfers and Servicing [Abstract]
Transfers and Servicing of Financial Assets (Including Mortgage Banking Activity)	TRANSFERS AND SERVICING OF FINANCIAL ASSETS (INCLUDING MORTGAGE BANKING ACTIVITY) Commercial Banking Activity The unpaid principal balances of loans serviced for others were $1.0 billion and $888.4 million at December 31, 2016 and 2015, respectively. Custodial escrow balances maintained in connection with the foregoing portfolio of loans serviced for others, and included in demand deposits, were not significant at December 31, 2016 and 2015. Mortgage Banking Activity IBERIABANK through its subsidiary, IMC, originates mortgage loans for sale into the secondary market. The loans originated primarily consist of residential first mortgages that conform to standards established by the GSEs, but can also consist of junior lien loans secured by residential property. These sales are primarily to private companies that are unaffiliated with the GSEs on a servicing-released basis. During 2016, $14.0 million of mortgage loans held for sale for which the fair value option was elected were transferred from loans held for sale to loans held for investment. Changes to the carrying amount of mortgage loans held for sale at December 31 are presented in the following table. (Dollars in thousands) 2016 2015 2014 Balance at beginning of period $ 166,247 $ 140,072 $ 128,442 Originations and purchases 2,460,033 2,464,588 1,675,538 Sales, net of gains (2,451,459 ) (2,432,979 ) (1,657,409 ) Mortgage loans transferred to held for investment (14,017 ) — — Other (3,763 ) (5,434 ) (6,499 ) Balance at end of period $ 157,041 $ 166,247 $ 140,072 The following table details the components of mortgage income for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Fair value changes of derivatives and mortgage loans held for sale: Mortgage loans held for sale and derivatives $ 1,361 $ 2,216 $ 631 Derivative settlements, net (6,640 ) (5,017 ) (8,743 ) Gains on sales 87,925 82,671 59,156 Servicing and other income, net 1,207 792 753 $ 83,853 $ 80,662 $ 51,797 Servicing Rights Servicing rights are recorded at the lower of cost or market value in “other assets” on the Company's consolidated balance sheets and amortized over the remaining servicing life of the loans, with consideration given to prepayment assumptions. Mortgage servicing rights had the following carrying values as of the periods indicated: December 31, 2016 December 31, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount (Dollars in thousands) Mortgage servicing rights $ 7,202 $ (3,144 ) $ 4,058 $ 6,104 $ (2,320 ) $ 3,784 In addition, there was an insignificant amount of non-mortgage servicing rights related to SBA loans as of December 31, 2016 and no non-mortgage servicing rights as of December 31, 2015.

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Premises and Equipment	PREMISES AND EQUIPMENT Premises and equipment consisted of the following at December 31: (Dollars in thousands) 2016 2015 Land $ 84,616 $ 84,438 Buildings 239,626 245,934 Furniture, fixtures and equipment 115,775 140,031 Total premises and equipment 440,017 470,403 Accumulated depreciation (133,644 ) (146,501 ) Total premises and equipment, net $ 306,373 $ 323,902 Depreciation expense was $20.8 million , $22.2 million , and $19.4 million , for the years ended December 31, 2016, 2015, and 2014, respectively. The Company actively engages in leasing office space available in buildings it owns. Leases have different terms ranging from monthly rental to 16 years . For the year ended December 31, 2016, income from these leases averaged $0.2 million per month. Total lease income for the years ended December 31, 2016, 2015, and 2014 was $2.8 million , $2.4 million , and $1.6 million , respectively. Income from leases is reported as a reduction in occupancy and equipment expense. The total allocated cost of the portion of the buildings held for lease at December 31, 2016 and 2015 was $8.7 million and $8.2 million , respectively, with related accumulated depreciation of $3.1 million and $2.6 million , respectively. The Company leases certain branch and corporate offices, land and ATM facilities through operating leases with terms that range from one to 50 years , some of which contain renewal options and escalation clauses under various terms. In addition, some have early termination clauses. Rent expense for the years ended December 31, 2016, 2015, and 2014 totaled $16.6 million , $15.4 million , and $10.9 million , respectively. Minimum future annual rent commitments under lease agreements for the periods indicated are as follows: (Dollars in thousands) 2017 $ 15,927 2018 14,981 2019 13,980 2020 12,742 2021 10,906 2022 and thereafter 37,527 $ 106,063

Goodwill and Other Acquired Int

Goodwill and Other Acquired Intangible Assets	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Acquired Intangible Assets	GOODWILL AND OTHER ACQUIRED INTANGIBLE ASSETS Goodwill Changes to the carrying amount of goodwill by reporting unit for the years ended December 31, 2016 and 2015 are provided in the following table. (Dollars in thousands) IBERIABANK IMC LTC Total Balance, December 31, 2014 $ 489,183 $ 23,178 $ 5,165 $ 517,526 Goodwill acquired during the year 207,077 — — 207,077 Balance, December 31, 2015 $ 696,260 $ 23,178 $ 5,165 $ 724,603 Goodwill adjustments during the year 2,253 — — 2,253 Balance, December 31, 2016 $ 698,513 $ 23,178 $ 5,165 $ 726,856 The goodwill adjustments during 2016 are the result of the finalization of fair value estimates related to the 2015 acquisitions of Florida Bank Group, Old Florida, and Georgia Commerce during the respective measurement periods. See Note 3 for further information on these acquisitions. The Company performed the required annual goodwill impairment test as of October 1, 2016. The Company’s annual impairment test did not indicate impairment in any of the Company’s reporting units as of the testing date. Following the testing date, management evaluated the events and changes that could indicate that goodwill might be impaired and concluded that a subsequent test was not necessary. Title Plant The Company held title plant assets recorded in “other assets” on the Company's consolidated balance sheets totaling $6.7 million at both December 31, 2016 and 2015. No events or changes in circumstances occurred during 2016 to suggest the carrying value of the title plant was not recoverable. Intangible assets subject to amortization Definite-lived intangible assets had the following carrying values included in “other assets” on the Company’s consolidated balance sheets as of December 31: 2016 2015 (Dollars in thousands) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Core deposit intangibles $ 74,001 $ (52,165 ) $ 21,836 $ 74,001 $ (43,957 ) $ 30,044 Customer relationship intangible asset 1,348 (1,064 ) 284 1,348 (984 ) 364 Non-compete agreement 63 (22 ) 41 100 (79 ) 21 Other intangible assets — — — 205 (114 ) 91 Total $ 75,412 $ (53,251 ) $ 22,161 $ 75,654 $ (45,134 ) $ 30,520 The related amortization expense of intangible assets is as follows: (Dollars in thousands) Amount Aggregate amortization expense for the years ended December 31: 2014 $ 5,807 2015 7,811 2016 8,415 (Dollars in thousands) Estimated amortization expense for the years ended December 31: 2017 $ 6,733 2018 5,740 2019 5,019 2020 3,513 2021 1,066 2022 and thereafter 90

Derivative Instruments and Othe

Derivative Instruments and Other Hedging Activities	12 Months Ended
	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Other Hedging Activities	DERIVATIVE INSTRUMENTS AND OTHER HEDGING ACTIVITIES The Company enters into derivative financial instruments to manage interest rate risk, exposures related to liquidity and credit risk, and to facilitate customer transactions. The primary types of derivatives used by the Company include interest rate swap agreements, foreign exchange contracts, interest rate lock commitments, forward sales commitments, written and purchased options and credit derivatives. All derivative instruments are recognized on the consolidated balance sheets as "other assets" or "other liabilities" at fair value, as required by ASC Topic 815, Derivatives and Hedging . For cash flow hedges, the effective portion of the gain or loss related to the derivative instrument is initially reported as a component of other comprehensive income and subsequently reclassified into earnings when the forecasted transaction affects earnings or when the hedge is terminated. The ineffective portion of the gain or loss is reported in earnings immediately. In applying hedge accounting for derivatives, the Company establishes and documents a method for assessing the effectiveness of the hedging derivative and a measurement approach for determining the ineffective aspect of the hedge upon the inception of the hedge. The Company has designated interest rate swaps in a cash flow hedge to convert forecasted variable interest payments to a fixed rate on its junior subordinated debt and has concluded that the forecasted transactions are probable of occurring. For derivative instruments that are not designated as hedging instruments, changes in the fair value of the derivatives are recognized in earnings immediately. Information pertaining to outstanding derivative instruments is as follows: Balance Sheet Location Asset Derivatives Fair Value Balance Sheet Location Liability Derivatives Fair Value (Dollars in thousands) December 31, 2016 December 31, 2015 December 31, 2016 December 31, 2015 Derivatives designated as hedging instruments under ASC Topic 815: Interest rate contracts Other assets $ — $ 58 Other liabilities $ 525 $ — Total derivatives designated as hedging instruments under ASC Topic 815 $ — $ 58 $ 525 $ — Derivatives not designated as hedging instruments under ASC Topic 815: Interest rate contracts Other assets $ 20,719 $ 18,077 Other liabilities $ 20,719 $ 18,077 Foreign exchange contracts Other assets 27 156 Other liabilities 26 134 Forward sales contracts Other assets 6,014 1,588 Other liabilities 794 474 Written and purchased options Other assets 12,125 10,607 Other liabilities 8,098 6,254 Other contracts Other assets 1 — Other liabilities 47 63 Total derivatives not designated as hedging instruments under ASC Topic 815 38,886 30,428 29,684 25,002 Total $ 38,886 $ 30,486 $ 30,209 $ 25,002 Asset Derivatives Notional Amount Liability Derivatives Notional Amount (Dollars in thousands) December 31, 2016 December 31, 2015 December 31, 2016 December 31, 2015 Derivatives designated as hedging instruments under ASC Topic 815: Interest rate contracts $ — $ 108,500 $ 108,500 $ — Total derivatives designated as hedging instruments under ASC Topic 815 $ — $ 108,500 $ 108,500 $ — Derivatives not designated as hedging instruments under ASC Topic 815: Interest rate contracts $ 1,033,955 $ 590,334 $ 1,033,955 $ 590,334 Foreign exchange contracts 4,474 4,392 4,474 4,392 Forward sales contracts 229,181 223,841 120,567 173,430 Written and purchased options 289,115 328,210 154,170 181,949 Other contracts 8,784 — 106,518 43,169 Total derivatives not designated as hedging instruments under ASC Topic 815 $ 1,565,509 $ 1,146,777 $ 1,419,684 $ 993,274 Total $ 1,565,509 $ 1,255,277 $ 1,528,184 $ 993,274 The Company has entered into risk participation agreements with counterparties to transfer or assume credit exposures related to interest rate derivatives. The notional amounts of risk participation agreements sold were $106.5 million and $43.2 million at December 31, 2016 and December 31, 2015, respectively. Assuming all underlying third party customers referenced in the swap contracts defaulted at December 31, 2016 and December 31, 2015, the exposure from these agreements would not be material based on the fair value of the underlying swaps. The Company is party to collateral agreements with certain derivative counterparties. Such agreements require that the Company maintain collateral based on the fair values of individual derivative transactions. In the event of default by the Company, the counterparty would be entitled to the collateral. At December 31, 2016 and 2015, the Company was required to post $1.9 million and $10.9 million , respectively, in cash or securities as collateral for its derivative transactions, which are included in "interest-bearing deposits in banks" on the Company’s consolidated balance sheets. The Company does not anticipate additional assets will be required to be posted as collateral, nor does it believe additional assets would be required to settle its derivative instruments immediately if contingent features were triggered at December 31, 2016. The Company’s master netting agreements represent written, legally enforceable bilateral agreements that (1) create a single legal obligation for all individual transactions covered by the master agreement and (2) in the event of default, provide the non-defaulting counterparty the right to accelerate, terminate, and close-out on a net basis all transactions under the agreement and to promptly liquidate or set-off collateral posted by the defaulting counterparty. As permitted by U.S. GAAP, the Company does not offset fair value amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral against recognized fair value amounts of derivatives executed with the same counterparty under a master netting agreement. The following table reconciles the gross amounts presented in the consolidated balance sheets to the net amounts that would result in the event of offset. December 31, 2016 Gross Amounts Presented in the Balance Sheet Gross Amounts Not Offset in the Balance Sheet Net (Dollars in thousands) Derivatives Collateral (1) Derivatives subject to master netting arrangements Derivative assets Interest rate contracts not designated as hedging instruments $ 20,719 $ (9,677 ) $ — $ 11,042 Written and purchased options 8,085 — — 8,085 Total derivative assets subject to master netting arrangements $ 28,804 $ (9,677 ) $ — $ 19,127 Derivative liabilities Interest rate contracts designated as hedging instruments $ 525 $ — $ (181 ) $ 344 Interest rate contracts not designated as hedging instruments 20,719 (9,677 ) (1,711 ) 9,331 Total derivative liabilities subject to master netting arrangements $ 21,244 $ (9,677 ) $ (1,892 ) $ 9,675 (1) Consists of cash collateral recorded at cost, which approximates fair value, and investment securities . December 31, 2015 Gross Amounts Presented in the Balance Sheet Gross Amounts Not Offset in the Balance Sheet Net (Dollars in thousands) Derivatives Collateral (1) Derivatives subject to master netting arrangements Derivative assets Interest rate contracts designated as hedging instruments $ 100 $ (43 ) $ — $ 57 Interest rate contracts not designated as hedging instruments 18,241 (119 ) — 18,122 Written and purchased options 6,255 — — 6,255 Total derivative assets subject to master netting arrangements $ 24,596 $ (162 ) $ — $ 24,434 Derivative liabilities Interest rate contracts designated as hedging instruments $ 43 $ (43 ) $ — $ — Interest rate contracts not designated as hedging instruments 18,241 (119 ) (10,877 ) 7,245 Total derivative liabilities subject to master netting arrangements $ 18,284 $ (162 ) $ (10,877 ) $ 7,245 (1) Consists of cash collateral recorded at cost, which approximates fair value, and investment securities. During the years ended December 31, 2016 and 2015, the Company has not reclassified into earnings any gain or loss as a result of the discontinuance of cash flow hedges, because it was probable the original forecasted transaction would not occur by the end of the originally specified term. At December 31, 2016, the Company does not expect to reclassify a material amount from accumulated other comprehensive income into interest income over the next twelve months for derivatives that will be settled. At December 31, 2016, 2015, and 2014, and for the years then ended, information pertaining to the effect of the hedging instruments on the consolidated financial statements is as follows: Location of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) Amount of Gain (Loss) Recognized in OCI net of taxes (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income net of taxes (Effective Portion) (Dollars in thousands) For the Years Ended December 31 Derivatives in ASC Topic 815 Cash Flow Hedging Relationships 2016 2015 2014 2016 2015 2014 2016 2015 2014 Interest rate contracts $ (428 ) $ 38 $ — Interest expense $ 50 $ — $ — Interest expense $ — $ — $ (1 ) Total $ (428 ) $ 38 $ — $ 50 $ — $ — $ — $ — $ (1 ) Information pertaining to the effect of derivatives not designated as hedging instruments on the consolidated financial statements as of December 31, is as follows: Location of Gain (Loss) Recognized in Income on Derivatives Amount of Gain (Loss) Recognized in Income on Derivatives (Dollars in thousands) 2016 2015 2014 Interest rate contracts (1) Other income $ 8,830 $ 4,143 $ 2,513 Foreign exchange contracts Other income 15 22 — Forward sales contracts Mortgage income (1,731 ) (2,947 ) (3,225 ) Written and purchased options Mortgage income (327 ) 274 (5,739 ) Other contracts Other income 17 — — Total $ 6,804 $ 1,492 $ (6,451 ) (1) Includes fees associated with customer interest rate contracts. At December 31, additional information pertaining to outstanding interest rate swap agreements not designated as hedging instruments is as follows: (Dollars in thousands) 2016 2015 2014 Weighted average pay rate 4.1 % 3.2 % 2.9 % Weighted average receive rate 2.5 % 0.9 % 0.4 % Weighted average maturity in years 7.4 years 7.5 years 7.7 years Unrealized gain (loss) relating to interest rate swaps $ — $ — $ —

Deposits

Deposits	12 Months Ended
	Dec. 31, 2016
Banking and Thrift [Abstract]
Deposits	DEPOSITS Deposits at December 31 are summarized as follows: (Dollars in thousands) 2016 2015 Non-interest-bearing deposits $ 4,928,878 $ 4,352,229 Negotiable order of withdrawal (NOW) 3,314,281 2,974,176 Money market deposits accounts (MMDA) 6,219,532 6,010,882 Savings deposits 814,385 716,838 Certificates of deposit and other time deposits 2,131,207 2,124,623 $ 17,408,283 $ 16,178,748 Total time deposits summarized by denomination at December 31 are as follows: (Dollars in thousands) 2016 2015 Time deposits less than $250,000 $ 1,661,631 $ 1,456,804 Time deposits greater than $250,000 469,576 667,819 $ 2,131,207 $ 2,124,623 A schedule of maturities of all time deposits as of December 31, 2016 is as follows: (Dollars in thousands) Years ending December 31 2017 $ 1,335,041 2018 507,162 2019 96,509 2020 83,623 2021 60,468 2022 and thereafter 48,404 $ 2,131,207

Short-Term Borrowings

Short-Term Borrowings	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Short-Term Borrowings	SHORT-TERM BORROWINGS Short-term borrowings at December 31 are summarized as follows: (Dollars in thousands) 2016 2015 Federal Home Loan Bank advances $ 175,000 $ 110,000 Securities sold under agreements to repurchase 334,136 216,617 $ 509,136 $ 326,617 The levels of securities sold under agreements to repurchase and FHLB advances can fluctuate significantly on a day-to-day basis, depending on funding needs and which sources are used to satisfy those needs. All such arrangements are considered typical of the banking and brokerage industries and are accounted for as borrowings. Securities sold under agreements to repurchase, which are classified as secured borrowings, generally mature daily and are reflected at the amount of cash received in connection with the transaction. The Company may be required to provide additional collateral based on the fair value of the underlying securities. Additional information on the Company’s short-term borrowings for the years indicated is as follows: (Dollars in thousands) 2016 2015 2014 Outstanding at December 31 $ 509,136 $ 326,617 $ 845,742 Maximum month-end outstanding balance 807,993 798,933 1,034,741 Average daily outstanding balance 614,073 426,011 782,033 Average rate during the year 0.39 % 0.18 % 0.17 % Average rate at year end 0.30 % 0.20 % 0.18 %

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Long-Term Debt	LONG-TERM DEBT Long-term debt at December 31 is summarized as follows: (Dollars in thousands) 2016 2015 IBERIABANK: Federal Home Loan Bank notes, 0.864% to 7.040% $ 480,118 $ 136,628 Notes payable - Investment fund contribution, 7 to 40 year term, 0.50% to 3.60% fixed 28,725 83,709 508,843 220,337 IBERIABANK Corporation (junior subordinated debt): Statutory Trust I, 3 month LIBOR (1) , plus 3.25%, issued November 2002 10,310 10,310 Statutory Trust II, 3 month LIBOR (1) , plus 3.15%, issued June 2003 10,310 10,310 Statutory Trust III, 3 month LIBOR (1) , plus 2.00%, issued September 2004 10,310 10,310 Statutory Trust IV, 3 month LIBOR (1) , plus 1.60%, issued October 2006 15,464 15,464 American Horizons Statutory Trust I, 3 month LIBOR (1) , plus 3.15%, assumed January 2005 6,186 6,186 Statutory Trust V, 3 month LIBOR (1) , plus 1.435%, issued June 2007 10,310 10,310 Statutory Trust VI, 3 month LIBOR (1) , plus 2.75%, issued November 2007 12,372 12,372 Statutory Trust VII, 3 month LIBOR (1) , plus 2.54%, issued November 2007 13,403 13,403 Statutory Trust VIII, 3 month LIBOR (1) , plus 3.50%, issued March 2008 7,217 7,217 OMNI Trust I, 3 month LIBOR (1) , plus 3.30%, assumed May 2011 8,248 8,248 OMNI Trust II, 3 month LIBOR (1) , plus 2.79%, assumed May 2011 7,732 7,732 GA Commerce Trust II, 3 month LIBOR (1) , plus 1.64%, assumed May 2015 8,248 8,248 120,110 120,110 $ 628,953 $ 340,447 (1) The interest rate on the Company’s long-term debt indexed to LIBOR is based on the 3-month LIBOR rate. The 3-month LIBOR rate w as 1.00% and 0.61% at December 31, 2016 and 2015, respectively. Outstanding FHLB advances are a mix of bullet and amortizing structures. Amortizing FHLB advances are amortized over periods ranging from 1.5 to 30 years , a nd have a balloon feature at maturity. Advances are collateralized by a blanket pledge of eligible loans, subject to contractual adjustments which reduce the borrowing base, as well as a secondary pledge of FHLB stock and FHLB demand deposits, the amount of which can exceed the amounts borrowed based on contractually required adjustments. Total additional FHLB advances for both short-term borrowings and long-term debt at December 31, 2016 w ere $4.9 billion und er the blanket floating lien including $1.5 billion from pledges of investment securities. The weighted average advance rate was 1.76% an d 3.79% at December 31, 2016 and 2015, respectively. Junior subordinated debt consists of a total of $120.1 million in Junior Subordinated Deferrable Interest Debentures of the Company issued to statutory trusts that were funded by the issuance of floating rate capital securities of the trusts. The terms of the junior subordinated debt are 30 years , and they are callable at par by the Company any time after 5 years . Interest is payable quarterly and may be deferred at any time at the election of the Company for up to 20 consecutive quarterly periods. During a deferral period, the Company is subject to certain restrictions, including being prohibited from declaring and paying dividends to its common shareholders. As of January 1, 2015, 75% of the Company's junior subordinated debt was excluded from Tier 1 capital for regulatory purposes. Effective January 1, 2016, the Company was subject to an additional 25% phase out of its junior subordinated debt from Tier 1 capital. As a result, 100% of the Company's junior subordinated debt is excluded from Tier 1 capital (but included in Tier 2 capital) at December 31, 2016. Advances and long-term debt at December 31, 2016 have maturities or call dates in future years as follows: (Dollars in thousands) 2017 $ 55,516 2018 233,667 2019 97,042 2020 15,263 2021 55,564 2022 and thereafter 171,901 $ 628,953

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES The provision for income tax expense consists of the following for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Current expense $ 103,335 $ 67,025 $ 69,612 Deferred expense (benefit) (16,654 ) 4,551 (25,027 ) Tax credits (7,112 ) (11,268 ) (12,012 ) Amortization on qualified affordable housing tax credits 4,185 2,023 1,005 Tax benefits attributable to items charged to equity and goodwill 1,439 1,763 2,105 $ 85,193 $ 64,094 $ 35,683 There was a balance payable of $2 million and a balance receivable of $13 million for federal and state income taxes at December 31, 2016 and 2015, respectively. The provision for federal income taxes differs from the amount computed by applying the federal income tax statutory rate of 35 percent on income before income tax expense as indicated in the following analysis for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Federal tax based on statutory rate $ 95,189 $ 72,428 $ 49,373 Increase (decrease) resulting from: Effect of tax-exempt income (8,203 ) (6,919 ) (7,064 ) Interest and other nondeductible expenses 3,250 5,899 2,642 State taxes, net of federal benefit 4,770 3,955 2,531 Tax credits (7,112 ) (11,268 ) (12,012 ) Amortization on qualified affordable housing tax credits 4,185 2,023 1,005 Other (6,886 ) (2,024 ) (792 ) $ 85,193 $ 64,094 $ 35,683 Effective tax rate 31.3 % 31.0 % 25.3 % The composition of other items resulting in a net tax benefit of $6.9 million for the year ending December 31, 2016 arose principally from completion of a study concluding existence of $6.5 million net unrealized built-in gains on the 2015 Florida Bank Group acquisition and $0.2 million of dividends on restricted stock. The Company recognized a $6.5 million deferred tax asset, a portion of which was claimed on the 2015 income tax return filed in the fourth quarter of 2016. The net deferred tax asset at December 31 is as follows: (Dollars in thousands) 2016 2015 Deferred tax asset: NOL carryforward $ 19,584 $ 17,258 Allowance for credit losses 58,036 56,446 Deferred compensation 10,852 7,528 Basis difference in acquired assets 32,923 48,256 Unrealized loss on securities available for sale 14,019 854 OREO 4,498 6,210 Other 14,754 10,438 154,666 146,990 Deferred tax liability: Basis difference in acquired assets (13,150 ) (31,975 ) Gain on acquisition — (212 ) FHLB stock (270 ) (122 ) Premises and equipment (6,132 ) (1,658 ) Acquisition intangibles (8,134 ) (7,648 ) Deferred loan costs (4,702 ) (4,610 ) Investments acquired — (167 ) Other (9,196 ) (16,694 ) (41,584 ) (63,086 ) Net deferred tax asset $ 113,082 $ 83,904 Net operating loss carryforwards arising from acquisitions during 2015 expire over a 20 -year period and will be utilized subject to annual Internal Revenue Code Section 382 limitations. No benefit was recognized at acquisition for net operating losses that will expire unused due to the IRS limitations. The Company determined that the net deferred tax asset is more likely than not to be realized based on an assessment of all available positive and negative evidence and therefore no valuation allowance has been recorded as of December 31, 2016 or 2015. Retained earnings at December 31, 2016 and 2015 included approximately $21.9 million accumulated prior to January 1, 1987 for which no provision for federal income taxes has been made. If this portion of retained earnings is used in the future for any purpose other than to absorb bad debts, it will be added to future taxable income. The Company does not believe it has any unrecognized tax benefits included in its consolidated financial statements. The Company has not had any settlements in the current period with taxing authorities, nor has it recognized tax benefits as a result of a lapse of the applicable statute of limitations. During the years ended December 31, 2016, 2015, and 2014, the Company did not recognize any interest or penalties in its consolidated financial statements, nor has it recorded a liability for interest or penalty payments.

Shareholders' Equity, Capital R

Shareholders' Equity, Capital Ratios and Other Regulatory Matters	12 Months Ended
	Dec. 31, 2016
Banking and Thrift [Abstract]
Shareholders' Equity, Capital Ratios and Other Regulatory Matters	SHAREHOLDERS' EQUITY, CAPITAL RATIOS AND OTHER REGULATORY MATTERS Preferred Stock On August 5, 2015, the Company issued an aggregate of 3,200,000 depositary shares (the “Series B Depositary Shares”), each representing a 1/400th ownership interest in a share of the Company’s 6.625% Fixed-to-Floating Non-Cumulative Perpetual Preferred Stock, Series B, par value $1.00 per share, (“Series B Preferred Stock”), with a liquidation preference of $10,000 per share of Series B Preferred Stock (equivalent to $25 per depositary share) which represents $80,000,000 in aggregate liquidation preference. On May 9, 2016, the Company issued an aggregate of 2,300,000 depositary shares (the “Series C Depositary Shares”), each representing a 1/400th ownership interest in a share of the Company’s 6.60% Fixed-to-Floating Non-Cumulative Perpetual Preferred Stock, Series C, par value $1.00 per share, (“Series C Preferred Stock”), with a liquidation preference of $10,000 per share of Series C Preferred Stock (equivalent to $25 per depositary share), which represents $57,500,000 in aggregate liquidation preference. The following table presents a summary of the Company's non-cumulative perpetual preferred stock: 2016 2015 Issuance Date Earliest Redemption Date Annual Dividend Rate Liquidation Amount Carrying Amount Carrying Amount (Dollars in millions) Series B Preferred Stock 8/5/2015 8/1/2025 6.625 % $ 80,000 $ 76,812 $ 76,812 Series C Preferred Stock 5/9/2016 5/1/2026 6.600 % 57,500 55,285 — $ 137,500 $ 132,097 $ 76,812 Dividends will accrue and be payable on the Series B Preferred Stock, if declared by the Company's Board of Directors, and will be paid semi-annually, in arrears, at an annual rate equal to 6.625% for each period from the issuance date up to and including August 1, 2025 and will be paid quarterly, in arrears, at an annual rate equal to three-month LIBOR plus 4.262% for each period after August 1, 2025. The Company may redeem the Series B Preferred Stock at its option, subject to regulatory approval, as described in the Company’s Registration Statement on Form 8-A, filed with the Securities and Exchange Commission on August 5, 2015. Dividends will accrue and be payable on the Series C Preferred Stock, if declared by the Company's Board of Directors, and will be paid quarterly, in arrears, at an annual rate equal to (i) 6.600% for each period from the issuance date to May 1, 2026 and (ii) three-month LIBOR plus 4.920% for each period on or after May 1, 2026. The Company may redeem the Series C Preferred Stock at its option, subject to regulatory approval, as described in the Company’s Registration Statement on Form 8-A, filed with the Securities and Exchange Commission on May 9, 2016. Common Stock During the second quarter of 2016, the Company's Board of Directors authorized the repurchase of up to 950,000 shares of IBERIABANK Corporation's outstanding common stock. Stock repurchases under this program will be made from time to time, on the open market or in privately negotiated transactions. The timing of these repurchases will depend on market conditions and other requirements. The share repurchase program does not obligate the Company to repurchase any dollar amount or number of shares, and the program may be extended, modified, suspended, or discontinued at any time. During 2016, the Company repurchased 202,506 common shares at a weighted average price of $57.61 per common share. On December 7, 2016, the Company issued an additional 3,593,750 shares of its common stock at a price of $81.50 per common share. Net proceeds from the offering, after deduction of underwriting discounts, commissions, and direct issuance costs, were $279.2 million . Regulatory Capital The Company and IBERIABANK are subject to various regulatory capital requirements administered by the federal and state banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s consolidated financial statements. Under capital adequacy regulations and the regulatory framework for prompt corrective action, the Company and IBERIABANK, as applicable, must meet specific capital guidelines that involve quantitative measures of their assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. The capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors. On January 1, 2015, the Company and IBERIABANK became subject to revised capital adequacy standards of the BCBS to address relevant provisions of the Dodd-Frank Act. Certain provisions of the new rules will be phased in from that date to January 1, 2019. The final rules: • Required that non-qualifying capital instruments, including trust preferred securities and cumulative perpetual preferred stock, must be fully phased out of Tier 1 capital by January 1, 2016, • Established new qualifying criteria for regulatory capital, including new limitations on the inclusion of deferred tax assets and mortgage servicing rights, • Required a minimum ratio of common equity Tier 1 capital (“CET1”) to risk-weighted assets of 4.5% , • Increased the minimum Tier 1 capital to risk-weighted assets ratio requirements from 4% to 6% , • Implemented a new capital conservation buffer requirement for a banking organization to maintain a buffer composed of CET1 capital in an amount greater than 2.5% above the minimum CET1 capital, Tier 1 capital and total risk-based capital ratios in order to avoid limitations on capital distributions, including dividend payments, and certain discretionary bonus payments to executive officers, with the buffer to be phased in beginning on January 1, 2016 at 0.625% and increasing annually until fully phased in at 2.5% by January 1, 2019. A banking organization with a buffer of less than the required amount would be subject to increasingly stringent limitations on certain distributions and payments as the buffer approaches zero, and • Increased capital requirements for past-due loans, high volatility commercial real estate exposures, and certain short-term commitments and securitization exposures. Management believes that, as of December 31, 2016 and 2015, the Company and IBERIABANK met all capital adequacy requirements to which they are subject. As of December 31, 2016, the most recent notification from the FRB categorized IBERIABANK as well-capitalized under the regulatory framework for prompt corrective action (the prompt corrective action requirements are not applicable to the Company). To be categorized as well-capitalized, an institution must maintain minimum total risk-based, Tier 1 risk-based and Tier 1 leverage ratios as set forth in the following table. There are no conditions or events since the notification that management believes have changed that categorization. The Company’s and IBERIABANK’s actual capital amounts and ratios as of December 31 are presented in the following table. (Dollars in thousands) 2016 Minimum Well-Capitalized Actual Amount Ratio Amount Ratio Amount Ratio Tier 1 Leverage Consolidated $ 818,440 4.00 % N/A N/A $ 2,221,528 10.86 % IBERIABANK 816,152 4.00 1,020,190 5.00 1,878,703 9.21 Common Equity Tier 1 (CET1) (1) Consolidated $ 794,334 4.50 % N/A N/A $ 2,089,431 11.84 % IBERIABANK 792,111 4.50 1,144,160 6.50 1,878,703 10.67 Tier 1 Risk-Based Capital (1) Consolidated $ 1,059,112 6.00 % N/A N/A $ 2,221,528 12.59 % IBERIABANK 1,056,147 6.00 1,408,197 8.00 1,878,703 10.67 Total Risk-Based Capital (1) Consolidated $ 1,412,149 8.00 % N/A N/A $ 2,493,988 14.13 % IBERIABANK 1,408,197 8.00 1,760,246 10.00 2,034,663 11.56 2015 Minimum Well-Capitalized Actual Amount Ratio Amount Ratio Amount Ratio Tier 1 Leverage Consolidated $ 751,798 4.00 % N/A N/A $ 1,790,034 9.52 % IBERIABANK 749,226 4.00 936,532 5.00 1,691,022 9.03 Common Equity Tier 1 (CET1) Consolidated $ 750,616 4.50 % N/A N/A $ 1,684,097 10.10 % IBERIABANK 748,667 4.50 1,081,408 6.50 1,691,022 10.16 Tier 1 Risk-Based Capital Consolidated $ 1,000,822 6.00 % N/A N/A $ 1,790,034 10.73 % IBERIABANK 998,223 6.00 1,330,964 8.00 1,691,022 10.16 Total Risk-Based Capital Consolidated $ 1,334,429 8.00 % N/A N/A $ 2,029,932 12.17 % IBERIABANK 1,330,964 8.00 1,663,705 10.00 1,843,545 11.08 (1) Beginning January 1, 2016, minimum capital ratios are subject to a capital conservation buffer. In order to avoid limitations on distributions, including dividend payments, and certain discretionary bonus payments to executive officers, an institution must hold a capital conservation buffer above its minimum risk-based capital requirements. This capital conservation buffer is calculated as the lowest of the differences between the actual CET1 ratio, Tier 1 Risk-Based Capital Ratio, and Total Risk-Based Capital ratio and the corresponding minimum ratios. At December 31, 2016, the required minimum capital conservation buffer was 0.625% , and will increase in subsequent years by 0.625% until it is fully phased in on January 1, 2019 at 2.50% . At December 31, 2016, the capital conservation buffers of the Company and IBERIABANK were 6.13% and 3.56% , respectively. Restrictions on Dividends, Loans and Advances IBERIABANK is restricted under applicable laws in the payment of dividends to an amount equal to current year earnings plus undistributed earnings for the immediately preceding year, unless prior permission is received from the Commissioner of Financial Institutions for the State of Louisiana. Dividends payable by IBERIABANK in 2017 without permission will be limited to 2017 earnings plus an additional $191.0 million . Funds available for loans or advances by IBERIABANK to the Parent amounted to $187.9 million . In addition, any dividends that may be paid by IBERIABANK to the Parent would be restricted if IBERIABANK did not comply with the above-described capital conservation buffer requirements and would be prohibited if the effect thereof would cause IBERIABANK’s capital to be reduced below applicable minimum capital requirements. During any deferral period under the Company’s junior subordinated debt, the Company would be prohibited from declaring and paying dividends to preferred and common shareholders. In addition, so long as any shares of Series B Preferred Stock or Series C Preferred Stock remain outstanding, we are prohibited from paying dividends on any of our common stock if the required payments on our Series B Preferred Stock and Series C Preferred Stock have not been made. See Note 14 to the consolidated financial statements for additional information.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE Share-based payment awards that entitle holders to receive non-forfeitable dividends before vesting are considered participating securities that are included in the calculation of earnings per share using the two-class method. The two-class method is an earnings allocation formula under which earnings per share is calculated for common stock and participating securities according to dividends declared and participating rights in undistributed earnings. Under this method, all earnings, distributed and undistributed, are allocated to common shares and participating securities based on their respective rights to receive dividends. The following table presents the calculation of basic and diluted earnings per share for the periods indicated. For the Years Ended December 31, (In thousands, except per share data) 2016 2015 2014 Earnings per common share - basic Net income $ 186,777 $ 142,844 $ 105,382 Preferred stock dividends (7,977 ) — — Dividends and undistributed earnings allocated to unvested restricted shares (1,872 ) (1,680 ) (1,651 ) Net income allocated to common shareholders - basic $ 176,928 $ 141,164 $ 103,731 Weighted average common shares outstanding 40,948 38,214 31,307 Earnings per common share - basic 4.32 3.69 3.31 Earnings per common share - diluted Net income allocated to common shareholders - basic $ 176,928 $ 141,164 $ 103,731 Dividends and undistributed earnings allocated to unvested restricted shares (37 ) (48 ) (34 ) Net income allocated to common shareholders - diluted $ 176,891 $ 141,116 $ 103,697 Weighted average common shares outstanding 40,948 38,214 31,307 Dilutive potential common shares 158 96 126 Weighted average common shares outstanding - diluted 41,106 38,310 31,433 Earnings per common share - diluted $ 4.30 $ 3.68 $ 3.30 For the years ended December 31, 2016 , 2015 , and 2014 , the calculations for basic shares outstanding exclude the weighted average shares owned by the Recognition and Retention Plan (“RRP”) of 447,818 ; 607,608 ; and 625,555 , respectively. The effects from the assumed exercises of 155,969 ; 159,236 ; and 13,101 stock options were not included in the computation of diluted earnings per share for the years ended December 31, 2016 , 2015 , and 2014 , respectively, because such amounts would have had an antidilutive effect on earnings per common share.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	SHARE-BASED COMPENSATION The Company has various types of share-based compensation plans that permit the granting of awards in the form of stock options, restricted stock, restricted share units, phantom stock and performance units. These plans are administered by the Compensation Committee of the Board of Directors, which selects persons eligible to receive awards and determines the terms, conditions and other provisions of the awards. At December 31, 2016, awards of 2,456,052 shares could be made under approved incentive compensation plans. The Company issues shares to fulfill stock option exercises and restricted share units and restricted stock awards vesting from available authorized common shares. At December 31, 2016, the Company believes there are adequate authorized shares to satisfy anticipated stock option exercises and restricted share unit and restricted stock award vesting. Stock option awards The Company issues stock options under various plans to directors, officers and other key employees. The option exercise price cannot be less than the fair value of the underlying common stock as of the date of the option grant and the maximum option term cannot exceed ten years . The following table represents the activity related to stock options during the periods indicated: Number of Shares Weighted Average Exercise Price Aggregate Intrinsic Value (Dollars in thousands) Weighted Average Remaining Contract Life (in years) Outstanding options, December 31, 2013 1,072,829 $ 53.47 Granted 77,434 65.31 Exercised (267,421 ) 48.57 $ 4,612 Forfeited or expired (15,160 ) 60.38 Outstanding options, December 31, 2014 867,682 $ 55.92 Granted 82,001 62.50 Exercised (119,917 ) 51.71 1,516 Forfeited or expired (15,989 ) 66.52 Outstanding options, December 31, 2015 813,777 $ 56.99 Granted 160,624 48.65 Exercised (196,769 ) 55.39 3,597 Forfeited or expired (56,094 ) 59.49 Outstanding options, December 31, 2016 721,538 $ 55.38 $ 20,583 6.0 Exercisable options, December 31, 2014 562,752 55.92 Exercisable options, December 31, 2015 546,842 $ 56.54 Exercisable options, December 31, 2016 415,376 $ 56.66 $ 11,366 4.4 The following table represents weighted average remaining life as of December 31, 2016 for options outstanding within the stated exercise prices: Options Outstanding Options Exercisable Exercise Price Range Per Share Number of Options Weighted Average Exercise Price Weighted Average Remaining Life Number of Options Weighted Average Exercise Price $36.48 to $47.50 147,913 $ 47.27 8.9 years 5,849 $ 45.42 $47.51 to $52.35 151,527 51.56 4.9 years 113,328 51.51 $52.36 to $54.82 116,558 53.39 4.6 years 90,653 53.68 $54.83 to $59.81 68,683 56.33 3.7 years 64,387 56.17 $59.82 to $62.82 154,506 61.32 5.7 years 98,688 60.63 $62.83 to $111.71 82,351 67.83 7.1 years 42,471 69.81 Total options 721,538 $ 55.38 6.0 years 415,376 $ 56.66 The Company uses the Black-Scholes option pricing model to estimate the fair value of stock option awards. The following weighted-average assumptions were used for option awards issued during the years ended December 31: 2016 2015 2014 Expected dividends 2.8 % 2.2 % 2.1 % Expected volatility 29.0 % 35.6 % 35.8 % Risk-free interest rate 1.4 % 2.0 % 2.3 % Expected term (in years) 6.5 7.5 7.5 Weighted-average grant-date fair value $ 10.46 $ 19.57 $ 21.26 The assumptions above are based on multiple factors, including historical stock option exercise patterns and post-vesting employment termination behaviors, expected future exercise patterns and the expected volatility of the Company’s stock price. The following table represents the compensation expense that is included in non-interest expense and related income tax benefits in the accompanying consolidated statements of comprehensive income related to stock options for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Compensation expense related to stock options $ 2,010 $ 1,861 $ 2,053 Income tax benefit related to stock options 331 317 375 At December 31, 2016, there was $2.1 million of unrecognized compensation cost related to stock options that is expected to be recognized over a weighted-average period of 2.6 years . Restricted stock awards The Company issues restricted stock under various plans for certain officers and directors. The restricted stock awards may not be sold or otherwise transferred until certain restrictions have lapsed. The holders of the restricted stock receive dividends and have the right to vote the shares. The compensation expense for these awards is determined based on the market price of the Company's common stock at the date of grant applied to the total number of shares granted and is recognized over the vesting period (generally three to seven years). As of December 31, 2016 and 2015, unrecognized share-based compensation associated with these awards totaled $16.0 million and $19.5 million , respectively. The unrecognized compensation cost related to restricted stock awards at December 31, 2016 is expected to be recognized over a weighted-average period of 2.2 years . Restricted share units In 2015, the Company issued restricted share units to certain of its executive officers. Restricted share units vest after the end of a three year performance period, based on satisfaction of the market and performance conditions set forth in the restricted share unit agreement. Recipients do not possess voting or investment power over the common stock underlying such units until vesting. The grant date fair value of these restricted share units is the same as the value of the corresponding number of shares of common stock, adjusted for assumptions surrounding the market-based conditions contained in the respective agreements. See Note 1 for further discussion of restricted share units with market or performance conditions. The following table represents the compensation expense that was included in non-interest expense and related income tax benefits in the accompanying consolidated statements of comprehensive income related to restricted stock awards and restricted share units for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Compensation expense related to restricted stock awards and restricted share units $ 12,513 $ 12,045 $ 9,932 Income tax benefit related to restricted stock awards and restricted share units 4,380 4,215 3,476 The following table represents unvested restricted stock award and restricted share unit activity for the years ended December 31: 2016 2015 2014 Balance at beginning of period 507,130 506,289 523,756 Granted 254,276 207,575 168,254 Forfeited (28,855 ) (26,970 ) (18,171 ) Earned and issued (189,290 ) (179,764 ) (167,550 ) Balance at end of period 543,261 507,130 506,289 The weighted average grant date fair value of restricted stock awards and restricted share units granted was $48.84 , $63.16 , and $65.11 for the years ended December 31, 2016, 2015, and 2014, respectively. The total fair value of restricted stock awards and restricted share units vested during the years ended December 31, 2016, 2015, and 2014 was $10.7 million , $11.3 million , and $10.9 million , respectively. Phantom stock awards The Company issues phantom stock awards to certain key officers and employees. The awards are subject to a vesting period of five to seven years and are paid out in cash upon vesting. The amount paid per vesting period is calculated as the number of vested “share equivalents” multiplied by the closing market price of a share of the Company’s common stock on the vesting date. Share equivalents are calculated on the date of grant as the total award’s dollar value divided by the closing market price of a share of the Company’s common stock on the grant date. Award recipients are also entitled to a “dividend equivalent” on each unvested share equivalent held by the award recipient. A dividend equivalent is a dollar amount equal to the cash dividends that the participant would have been entitled to receive if the participant’s share equivalents were issued in shares of common stock. Dividend equivalents are reinvested as share equivalents that will vest and be paid out on the same date as the underlying share equivalents on which the dividend equivalents were paid. The number of share equivalents acquired with a dividend equivalent is determined by dividing the aggregate of dividend equivalents paid on the unvested share equivalents by the closing price of a share of the Company’s common stock on the dividend payment date. Performance units In 2016 and 2015, the Company issued performance units to certain of its executive officers. Performance units are tied to the value of shares of the Company's common stock, are payable in cash, and vest in increments of one-third per year after attainment of one or more performance measures. The value of performance units is the same as the value of the corresponding number of shares of common stock. The following table indicates compensation expense recorded for phantom stock and performance units based on the number of share equivalents vested at December 31 of the years indicated and the current market price of the Company’s stock at that time: (Dollars in thousands) 2016 2015 2014 Compensation expense related to phantom stock and performance units $ 12,933 $ 12,109 $ 5,496 The following table represents phantom stock award and performance unit activity during the periods indicated. (Dollars in thousands) Number of share equivalents (1) Value of share equivalents (2) Balance, December 31, 2013 433,884 $ 27,270 Granted 146,166 9,479 Forfeited share equivalents (22,800 ) 1,479 Vested share equivalents (81,903 ) 5,512 Balance, December 31, 2014 475,347 $ 30,826 Granted 167,573 9,228 Forfeited share equivalents (34,681 ) 1,910 Vested share equivalents (145,809 ) 9,288 Balance, December 31, 2015 462,430 $ 25,466 Granted 215,745 18,069 Forfeited share equivalents (42,051 ) 3,522 Vested share equivalents (163,294 ) 8,509 Balance, December 31, 2016 472,830 $ 39,600 (1) Number of share equivalents includes all reinvested dividend equivalents for the years indicated. (2) Except for share equivalents at the beginning of each period, which are based on the value at that time, and vested share payments, which are based on the cash paid at the time of vesting, the value of share equivalents is calculated based on the market price of the Company’s stock at the end of the respective periods. The market price of the Company’s stock was $83.75 , $55.07 and $64.85 on December 31, 2016, 2015 and 2014, respectively. 401(k) defined contribution plan The Company has a 401(k) Profit Sharing Plan covering substantially all of its employees. Annual employer contributions to the Plan are set by the Board of Directors. The Company made contributions of $1.9 million , $1.7 million , and $1.5 million for the years ended December 31, 2016, 2015, and 2014, respectively. The Plan provides, among other things, that participants in the Plan be able to direct the investment of their account balances within the Profit Sharing Plan into alternative investment funds. Participant deferrals under the salary reduction election may be matched by the employer based on a percentage to be determined annually by the employer.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Off-balance sheet commitments In the normal course of business, to meet the financing needs of its customers, the Company is a party to credit related financial instruments, with risk not reflected in the consolidated financial statements. These financial instruments include commitments to extend credit, standby letters of credit, and commercial letters of credit. Such commitments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the consolidated balance sheets. The credit policies used for these commitments are consistent with those used for on-balance sheet instruments. The Company’s exposure to credit loss in the event of non-performance by its customers under such commitments or letters of credit represents the contractual amount of the financial instruments as indicated in the table below. At December 31, 2016 and 2015, the fair value of guarantees under commercial and standby letters of credit was $1.6 million and $1.5 million , respectively. These amounts represent the unamortized fees associated with the guarantees and is included in “other liabilities” on the Company's consolidated balance sheets. This fair value will decrease as the existing commercial and standby letters of credit approach their expiration dates. At December 31, 2016 and 2015, respectively, the Company had the following financial instruments outstanding and related reserves, whose contract amounts represent credit risk: (Dollars in thousands) 2016 2015 Commitments to grant loans $ 355,558 $ 61,240 Unfunded commitments under lines of credit 4,899,930 4,617,802 Commercial and standby letters of credit 163,560 150,281 Reserve for unfunded lending commitments 11,241 14,145 Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to be drawn upon, the total commitment amounts generally represent future cash requirements. The Company evaluates each customer’s creditworthiness on a case-by-case basis. The amount of collateral, if any, is based on management’s credit evaluation of the customer. Unfunded commitments under commercial lines of credit, revolving credit lines, and overdraft protection agreements are commitments for possible future extensions of credit to existing customers. Many of these types of commitments do not contain a specified maturity date and may not be drawn upon to the total extent to which the Company is committed. See Note 6 for additional discussion related to the Company’s unfunded lending commitments. Commercial and standby letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer to a third party. These guarantees are primarily issued to support public and private borrowing arrangements, including commercial paper issuance, bond financing, and similar transactions. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers. When necessary they are collateralized, generally in the form of marketable securities and cash equivalents. Legal proceedings The nature of the business of the Company’s banking and other subsidiaries ordinarily results in a certain amount of claims, litigation, investigations, and legal and administrative cases and proceedings, which are considered incidental to the normal conduct of business. Some of these claims are against entities or assets of which the Company is a successor or acquired in business acquisitions. The Company has asserted defenses to these litigations and, with respect to such legal proceedings, intends to continue to defend itself vigorously, litigating or settling cases according to management’s judgment as to what is in the best interest of the Company and its shareholders. In July of 2016, a subsidiary of IBERIABANK received a subpoena from the Office of Inspector General of the U.S. Department of Housing and Urban Development (“HUD”) requesting information on certain previously originated loans insured by the Federal Housing Administration ("FHA") as well as other documents regarding the subsidiary's FHA-related policies and practices. The Company is cooperating with HUD and is in the process of responding to the subpoena. Given the current status of the matter, the Company is unable to determine if its submission of the information requested will result in an additional information request by HUD and/or further proceedings by HUD or other government agencies. The Company assesses its liabilities and contingencies in connection with outstanding legal proceedings utilizing the latest information available. Where it is probable that the Company will incur a loss and the amount of the loss can be reasonably estimated, the Company records a liability in its consolidated financial statements. These legal reserves may be increased or decreased to reflect any relevant developments on a quarterly basis. Where a loss is not probable or the amount of loss is not estimable, the Company does not accrue legal reserves. While the outcome of legal proceedings is inherently uncertain, based on information currently available, advice of counsel, and available insurance coverage, the Company’s management believes that it has established appropriate legal reserves. Any liabilities arising from pending legal proceedings are not expected to have a material adverse effect on the Company’s consolidated financial position, consolidated results of operations, or consolidated cash flows. However, it is possible that the ultimate resolution of these matters, if unfavorable, may be material to the Company’s consolidated financial position, consolidated results of operations, or consolidated cash flows. As of the date of this filing, the Company believes the amount of losses associated with legal proceedings that it is reasonably possible to incur above amounts already accrued is not material.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS Recurring fair value measurements The Company has segregated all financial assets and liabilities that are measured at fair value on a recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to estimate the fair value at the measurement date in the tables below. See Note 1, Summary of Significant Accounting Policies, for a description of how fair value measurements are determined. December 31, 2016 (Dollars in thousands) Level 1 Level 2 Level 3 Total Assets Securities available for sale $ — $ 3,446,097 $ — $ 3,446,097 Mortgage loans held for sale — 157,041 — 157,041 Derivative instruments — 38,886 — 38,886 Total $ — $ 3,642,024 $ — $ 3,642,024 Liabilities Derivative instruments $ — $ 30,209 $ — $ 30,209 Total $ — $ 30,209 $ — $ 30,209 December 31, 2015 Level 1 Level 2 Level 3 Total Assets Securities available for sale $ — $ 2,800,286 $ — $ 2,800,286 Mortgage loans held for sale — 166,247 — 166,247 Derivative instruments — 30,486 — 30,486 Total $ — $ 2,997,019 $ — $ 2,997,019 Liabilities Derivative instruments $ — $ 25,002 $ — $ 25,002 Total $ — $ 25,002 $ — $ 25,002 During 2016 and 2015, there were no transfers between the Level 1 and Level 2 fair value categories. Gains and losses (realized and unrealized) included in earnings (or accumulated other comprehensive income) during 2016 related to assets and liabilities measured at fair value on a recurring basis are reported in non-interest income or other comprehensive income as follows: (Dollars in thousands) Non-interest income Other comprehensive income (loss), net of tax Total gains (losses) included in earnings $ 5,567 $ — Change in unrealized gains (losses) relating to assets still held at December 31, 2016 — (24,450 ) Non-recurring fair value measurements The Company has segregated all assets and liabilities that are measured at fair value on a non-recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to determine the fair value at the measurement date in the tables below. December 31, 2016 (Dollars in thousands) Level 1 Level 2 Level 3 Total Assets Loans $ — $ — $ 93,485 $ 93,485 OREO, net — — 185 185 Total $ — $ — $ 93,670 $ 93,670 December 31, 2015 (Dollars in thousands) Level 1 Level 2 Level 3 Total Assets Loans $ — $ — $ 31,669 $ 31,669 OREO, net — — 1,662 1,662 Total $ — $ — $ 33,331 $ 33,331 The tables above exclude the initial measurement of assets and liabilities that were acquired as part of the acquisitions completed in 2015. These assets and liabilities were recorded at their fair value upon acquisition in accordance with U.S. GAAP and were not re-measured during the periods presented unless specifically required by U.S. GAAP. Acquisition date fair values represent either Level 2 fair value measurements (investment securities, property, equipment, and debt) or Level 3 fair value measurements (loans, OREO, deposits, and core deposit intangible assets). In accordance with the provisions of ASC Topic 310, the Company records certain loans considered impaired at their estimated fair value. A loan is considered impaired if it is probable the Company will be unable to collect all amounts due according to the contractual terms of the loan agreement. Fair value is measured at the estimated fair value of the collateral for collateral-dependent loans. Impaired loans with an unpaid principal balance of $125.5 million and $40.2 million were recorded at their fair value at December 31, 2016 and December 31, 2015, respectively. These loans are net of reserves and charge-offs of $32.0 million and $8.5 million included in the Company's allowance for credit losses at December 31, 2016 and December 31, 2015, respectively. The Company did not record any liabilities at fair value for which measurement of the fair value was made on a non-recurring basis during the years ended December 31, 2016, 2015 and 2014. Fair value option The Company has elected the fair value option for certain originated residential mortgage loans held for sale, which allows for a more effective offset of the changes in fair values of the loans and the derivative instruments used to hedge them without the burden of complying with the requirements for hedge accounting. The Company has $12.7 million of mortgage loans held for investment for which the fair value option was elected upon origination and continue to be accounted for at fair value. The following table summarizes the difference between the aggregate fair value and the aggregate unpaid principal balance for mortgage loans held for sale measured at fair value: December 31, 2016 December 31, 2015 (Dollars in thousands) Aggregate Fair Value Aggregate Unpaid Principal Aggregate Fair Value Less Unpaid Principal Aggregate Fair Value Aggregate Unpaid Principal Aggregate Fair Value Less Unpaid Principal Mortgage loans held for sale, at fair value $ 157,041 $ 153,801 $ 3,240 $ 166,247 $ 161,083 $ 5,164 Interest income on mortgage loans held for sale is recognized based on contractual rates and is reflected in interest income on loans held for sale in the consolidated statements of comprehensive income. Net gains (losses) resulting from the change in fair value of these loans that were recorded in mortgage income in the consolidated statements of comprehensive income totaled $2.1 million and ( $1.0 million ) for the years ended December 31, 2016 and 2015, respectively. The changes in fair value are mostly offset by economic hedging activities, with an insignificant portion of these changes attributable to changes in instrument-specific credit risk.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	FAIR VALUE OF FINANCIAL INSTRUMENTS The estimated fair value of a financial instrument is the current amount that would be exchanged between willing parties, other than in a forced liquidation. Fair value is best determined based upon quoted market prices. However, in many instances, there are no quoted market prices for the Company’s various financial instruments. In cases where quoted market prices are not available, fair values are based on estimates using present value or other valuation techniques. Those techniques are significantly affected by the assumptions used, including the discount rate and estimates of future cash flows. Accordingly, the fair value estimates may not be realized in an immediate settlement of the instrument. ASC Topic 825, Financial Instruments , excludes certain financial instruments and all non-financial instruments from its disclosure requirements. Consequently, the aggregate fair value amounts presented may not necessarily represent the underlying fair value of the Company. The carrying amount and estimated fair values, as well as the level within the fair value hierarchy, of the Company’s financial instruments are included in the tables below. See Note 1, Summary of Significant Accounting Policies, for a description of how fair value measurements are determined. December 31, 2016 (Dollars in thousands) Carrying Amount Fair Value Level 1 Level 2 Level 3 Financial Assets Cash and cash equivalents $ 1,362,126 $ 1,362,126 $ 1,362,126 $ — $ — Investment securities 3,535,313 3,536,029 — 3,536,029 — Loans and loans held for sale, net of unearned income and allowance for loan losses 15,077,293 15,066,055 — 157,041 14,909,014 FDIC loss share receivables — — — — — Derivative instruments 38,886 38,886 — 38,886 — Financial Liabilities Deposits $ 17,408,283 $ 16,762,475 $ — $ — $ 16,762,475 Short-term borrowings 509,136 509,136 334,136 175,000 — Long-term debt 628,953 617,656 — — 617,656 Derivative instruments 30,209 30,209 — 30,209 — December 31, 2015 (Dollars in thousands) Carrying Amount Fair Value Level 1 Level 2 Level 3 Financial Assets Cash and cash equivalents $ 510,267 $ 510,267 $ 510,267 $ — $ — Investment securities 2,899,214 2,901,247 — 2,901,247 — Loans and loans held for sale, net of unearned income and allowance for loan losses 14,355,297 14,674,749 — 166,247 14,508,502 FDIC loss share receivables 39,878 9,163 — — 9,163 Derivative instruments 30,486 30,486 — 30,486 — Financial Liabilities Deposits $ 16,178,748 $ 15,696,245 $ — $ — $ 15,696,245 Short-term borrowings 326,617 326,617 216,617 110,000 — Long-term debt 340,447 309,847 — — 309,847 Derivative instruments 25,002 25,002 — 25,002 — The fair value estimates presented herein are based upon pertinent information available to management as of December 31, 2016 and 2015. Although management is not aware of any factors that would significantly affect the estimated fair value amounts, such amounts have not been comprehensively revalued for purposes of these financial statements since that date and, therefore, current estimates of fair value may differ significantly from the amounts presented herein.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions	RELATED PARTY TRANSACTIONS In the ordinary course of business, the Company may execute transactions with various related parties. These transactions are consummated at terms equivalent to the prevailing market rates and terms at the time. Examples of such transactions may include lending or deposit arrangements, transfers of financial assets, services for administrative support, and other miscellaneous items. The Company has granted loans to executive officers and directors and their affiliates. These loans, including the related principal additions, principal payments, and unfunded commitments are not material to the consolidated financial statements at December 31, 2016 and 2015. None of the related party loans were classified as non-accrual, past due, troubled debt restructurings, or potential problem loans at December 31, 2016 and 2015, with the exception of the loan discussed below. IBERIABANK and several other financial institutions have extended credit (the “Credit Facility”) under a multi-bank syndicated credit facility to Stone Energy Corporation (the “Borrower"). One of the Company’s directors, David H. Welch, is the Chairman, President and Chief Executive Officer of the Borrower. IBERIABANK holds approximately 6 percent of the total commitments from twelve banks under the Credit Facility. On December 14, 2016, the Borrower filed for Chapter 11 Bankruptcy with the U.S. Bankruptcy Court in the Southern District of Texas. At the time of the filing, $341.5 million was outstanding under the Credit Facility. Of this amount, approximately $20.3 million was outstanding and due to IBERIABANK. At December 31, 2016 and as of the date of this Report, the outstanding amount due IBERIABANK under the Credit Facility remained on non-accrual status. On February 15, 2017, Borrower’s Second Amended Joint Prepackaged Plan of Reorganization (the “Plan”) was approved by the U.S. Bankruptcy Court. Pursuant to the Plan, banks under the Credit Facility are to be allowed a claim in the aggregate principal amount of $341.5 million , which was the principal amount outstanding under the Credit Facility at the time of the bankruptcy filing. The Plan further provides that banks under the Credit Facility are to receive, on account of their prepetition claims, (i) their respective pro rata share of commitments and obligations owing with respect to outstanding loans under a new 4 -year Reserve Based Lending Facility (the “Exit Facility”), and (ii) their respective pro rata share of prepetition cash as a partial repayment of such outstanding loans subject to re-borrowing to the extent permitted and pursuant to the terms of the Exit Facility held by such banks. As proposed under the Plan, the Exit Facility will differ from the Credit Facility with respect to the size of the facility and in certain other areas. These differences include, but are not limited to (i) a reduction in the facility size to $200 million , (ii) a reduction in the borrowing base from $360 million to $200 million , and (iii) both the facility size and borrowing base being subject to further, ratable, reduction in the event of certain other occurrences. Definitive agreements with respect to the Exit Facility have yet to be finalized and so we are unable to provide further information regarding the Exit Facility at this time. As confirmed, the Plan proposes a full recovery to the banks under the Credit Facility of their prepetition claims, including IBERIABANK’s prepetition claim of approximately $20.3 million . Deposits from related parties held by the Company were not material at December 31, 2016 and 2015.

Business Segments

Business Segments	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Business Segments	BUSINESS SEGMENTS Each of the Company’s reportable operating segments serves the specific needs of the Company’s customers based on the products and services it offers. The reportable segments are based upon those revenue-producing components for which separate financial information is produced internally and primarily reflect the manner in which resources are allocated and performance is assessed. Further, the reportable operating segments are also determined based on the quantitative thresholds prescribed within ASC Topic 280, Segment Reporting , and consideration of the usefulness of the information to the users of the consolidated financial statements. The Company reports the results of its operations through three reportable segments: IBERIABANK, IMC, and LTC. The IBERIABANK segment represents the Company’s commercial and retail banking functions, including its lending, investment, and deposit activities. IBERIABANK also includes the Company’s wealth management, capital markets, and other corporate functions. The IMC segment represents the Company’s origination, funding, and subsequent sale of one-to-four family residential mortgage loans. The LTC segment represents the Company’s title insurance and loan closing services. Certain expenses not directly attributable to a specific reportable segment are allocated to segments based on pre-determined methods that reflect utilization. Also within IBERIABANK are certain reconciling items that translate reportable segment results into consolidated results. The following tables present certain information regarding our operations by reportable segment, including a reconciliation of segment results to reported consolidated results for the periods presented. Reconciling items between segment results and reported results include: • Elimination of interest income and interest expense representing interest earned by IBERIABANK on interest-bearing checking accounts held by related companies, as well as the elimination of the related deposit balances at the IBERIABANK segment; • Elimination of investment in subsidiary balances on certain operating segments included in total and average segment assets; and • Elimination of intercompany due to and due from balances on certain operating segments that are included in total and average segment assets. Year Ended December 31, 2016 (Dollars in thousands) IBERIABANK IMC LTC Consolidated Interest and dividend income $ 707,676 $ 9,261 $ 2 $ 716,939 Interest expense 64,068 3,633 — 67,701 Net interest income 643,608 5,628 2 649,238 Provision for loan losses 44,336 88 — 44,424 Mortgage income 405 83,448 — 83,853 Title revenue — — 22,213 22,213 Other non-interest income 127,751 4 — 127,755 Allocated expenses (13,972 ) 10,686 3,286 — Non-interest expense 484,099 65,133 17,433 566,665 Income before income tax expense 257,301 13,173 1,496 271,970 Income tax expense 79,565 5,023 605 85,193 Net income $ 177,736 $ 8,150 $ 891 $ 186,777 Total loans and loans held for sale, net of unearned income $ 15,004,360 $ 217,652 $ — $ 15,222,012 Total assets 21,319,267 315,057 24,866 21,659,190 Total deposits 17,402,742 5,541 — 17,408,283 Average assets 19,959,261 335,913 26,060 20,321,234 Year Ended December 31, 2015 (Dollars in thousands) IBERIABANK IMC LTC Consolidated Interest and dividend income $ 639,793 $ 7,062 $ 3 $ 646,858 Interest expense 56,222 2,878 — 59,100 Net interest income 583,571 4,184 3 587,758 Provision for loan losses 30,908 — — 30,908 Mortgage income 966 79,696 — 80,662 Title revenue — — 22,837 22,837 Other non-interest income 116,903 (2 ) (7 ) 116,894 Allocated expenses (16,253 ) 12,036 4,217 — Non-interest expense 495,158 57,784 17,363 570,305 Income before income tax expense 191,627 14,058 1,253 206,938 Income tax expense 58,006 5,581 507 64,094 Net income $ 133,621 $ 8,477 $ 746 $ 142,844 Total loans and loans held for sale, net of unearned income $ 14,305,663 $ 188,012 $ — $ 14,493,675 Total assets 19,220,085 256,888 27,095 19,504,068 Total deposits 16,173,831 4,917 — 16,178,748 Average assets 18,146,216 230,819 25,671 18,402,706 Year Ended December 31, 2014 (Dollars in thousands) IBERIABANK IMC LTC Consolidated Interest and dividend income $ 498,820 $ 5,992 $ 3 $ 504,815 Interest expense 42,983 1,721 — 44,704 Net interest income 455,837 4,271 3 460,111 Provision for loan losses 18,966 94 — 19,060 Mortgage income 71 51,726 — 51,797 Title revenue — — 20,492 20,492 Other non-interest income 101,401 (61 ) (1 ) 101,339 Allocated expenses (11,602 ) 8,203 3,399 — Non-interest expense 412,165 44,761 16,688 473,614 Income before income tax expense 137,780 2,878 407 141,065 Income tax expense 34,352 1,148 183 35,683 Net income $ 103,428 $ 1,730 $ 224 $ 105,382 Total loans and loans held for sale, net of unearned income $ 11,415,973 $ 165,143 $ — $ 11,581,116 Total assets 15,537,731 194,156 26,017 15,757,904 Total deposits 12,515,329 5,196 — 12,520,525 Average assets 14,430,768 176,003 25,223 14,631,994

Condensed Parent Company Only F

Condensed Parent Company Only Financial Statements	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Parent Company Only Financial Statements	CONDENSED PARENT COMPANY ONLY FINANCIAL STATEMENTS Condensed financial statements of the Parent are shown below. The Parent has no significant operating activities. Condensed Balance Sheets (Dollars in thousands) December 31 2016 2015 Assets Cash in bank $ 436,792 $ 154,298 Investments in subsidiaries 2,635,682 2,449,325 Other assets 40,423 54,454 $ 3,112,897 $ 2,658,077 Liabilities and Shareholders’ Equity Liabilities $ 173,203 $ 159,242 Shareholders’ equity 2,939,694 2,498,835 $ 3,112,897 $ 2,658,077 Condensed Statements of Income Year Ended December 31 (Dollars in thousands) 2016 2015 2014 Operating income Reimbursement of management expenses $ 65,104 $ 59,255 $ 46,433 Other income 829 (329 ) 437 Total operating income 65,933 58,926 46,870 Operating expenses Interest expense 3,948 3,393 3,224 Salaries and employee benefits expense 45,623 41,689 31,981 Other expenses 19,566 17,492 14,576 Total operating expenses 69,137 62,574 49,781 Income (loss) before income tax benefit and increase in equity in undistributed earnings of subsidiaries (3,204 ) (3,648 ) (2,911 ) Income tax expense (benefit) 530 800 (518 ) Income (loss) before equity in undistributed earnings of subsidiaries (3,734 ) (4,448 ) (2,393 ) Equity in undistributed earnings of subsidiaries 190,511 147,292 107,775 Net Income 186,777 142,844 105,382 Preferred stock dividends (7,977 ) — — Net Income Available to Common Shareholders $ 178,800 $ 142,844 $ 105,382 Condensed Statements of Cash Flows (Dollars in thousands) Year Ended December 31 2016 2015 2014 Cash Flow from Operating Activities Net income $ 186,777 $ 142,844 $ 105,382 Adjustments to reconcile net income to net cash provided by operating activities: Depreciation and amortization 98 416 595 Net income of subsidiaries (190,511 ) (147,292 ) (107,775 ) Share-based compensation cost 14,523 13,906 11,985 Gain on sale of assets — (110 ) — Tax benefit associated with share-based payment arrangements (1,122 ) (580 ) (2,105 ) Other operating activities, net 12,417 82,105 (27,274 ) Net Cash Provided by (Used in) Operating Activities 22,182 91,289 (19,192 ) Cash Flow from Investing Activities Cash paid in excess of cash received for acquisitions — (5,054 ) 4,783 Proceeds from sale of premises and equipment — 12 — Purchases of premises and equipment — (2 ) (36 ) Return of capital from (Capital contributed to) subsidiary (6,000 ) 5,000 (14,600 ) Other investing activities, net (749 ) — — Net Cash (Used in) Investing Activities (6,749 ) (44 ) (9,853 ) Cash Flow from Financing Activities Cash dividends paid on common stock (56,793 ) (52,318 ) (43,070 ) Cash dividends paid on preferred stock (7,028 ) — — Net share-based compensation stock transactions 6,899 1,915 7,966 Payments to repurchase common stock (11,666 ) — — Net proceeds from issuance of common stock 279,242 — — Net proceeds from issuance of preferred stock 55,285 76,812 — Tax benefit associated with share-based payment arrangements 1,122 580 2,105 Net Cash Provided by (Used In) Financing Activities 267,061 26,989 (32,999 ) Net Increase (Decrease) in Cash and Cash Equivalents 282,494 118,234 (62,044 ) Cash and Cash Equivalents at Beginning of Period 154,298 36,064 98,108 Cash and Cash Equivalents at End of Period $ 436,792 $ 154,298 $ 36,064

Summary of Significant Accoun33

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Reclassification	Reclassification 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.
Principles of Consolidation	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 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 $84 million and $160 million at December 31, 2016 and 2015, 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. 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.
Nature of Operations	NATURE OF OPERATIONS The Company offers commercial and retail banking products and services to customers throughout locations in seven states through IBERIABANK. The Company also operates mortgage production offices in 10 states through 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 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. CDE is engaged in the purchase of tax credits.
Use of Estimates	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.
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, Georgia, 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 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 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 does not have any excessive concentrations to any one industry or customer.
Business Combinations	BUSINESS COMBINATIONS Assets and liabilities acquired in business combinations are recorded at their acquisition date fair values. In accordance with ASC Topic 805, Business Combinations , the Company generally records provisional amounts at the time of acquisition based on the information available to the Company. The provisional estimates of fair values may be adjusted for a period of up to one year (“measurement period”) from the date of acquisition if new information is obtained about facts and circumstances that existed as of the acquisition date that, if known, would have affected the measurement of the amounts recognized as of that date. Subsequent to the Company's early adoption of ASU No. 2015-16 during the third quarter of 2015, adjustments recorded during the measurement period are recognized in the current reporting period. Loans generally represent a significant portion of the assets acquired in the Company’s business acquisitions. If the Company discovers that it has materially underestimated the credit losses expected in the loan portfolio based on information available at the acquisition date within the measurement period, it will reduce or eliminate the gain and/or increase goodwill recorded on the acquisition in the period the adjustment is recorded. If the Company determines that losses arose subsequent to the acquisition date, such losses are reflected as a provision for credit losses.
Cash and Cash Equivalents	CASH AND CASH EQUIVALENTS For purposes of presentation in the consolidated statements of cash flows, cash and cash equivalents are defined as cash on hand, interest-bearing deposits, and non-interest-bearing demand deposits at other financial institutions with original maturities less than three months . IBERIABANK may be required to maintain average cash balances on hand or with the Federal Reserve Bank to meet regulatory reserve and clearing requirements. At December 31, 2016 and 2015, IBERIABANK had sufficient cash deposited with the Federal Reserve Bank to cover the required reserve balance.
Investment Securities	INVESTMENT SECURITIES Management determines the appropriate accounting classification of debt and equity securities at the time of acquisition and re-evaluates such designations at least quarterly. Debt securities that management has the ability and intent to hold to maturity are classified as HTM and carried at cost, adjusted for amortization of premiums and accretion of discounts using methods approximating the interest method. Securities acquired with the intention of recognizing short-term profits or which are actively bought and sold are classified as trading securities and reported at fair value, with unrealized gains and losses recognized in earnings. Securities not classified as HTM or trading, including equity securities with readily determinable fair values, are classified as AFS and recorded at fair value, with unrealized gains and losses excluded from earnings and reported in OCI. Credit-related declines in the fair value of debt and marketable equity securities that are considered OTTI are recorded in earnings. The Company evaluates its investment securities portfolio on a quarterly basis for indicators of OTTI. Declines in the fair value of individual HTM and AFS securities below their amortized cost basis are reviewed to determine whether the declines are other than temporary. In estimating OTTI losses, management considers 1) the length of time and the extent to which the fair value has been less than the amortized cost basis, 2) the financial condition and near-term prospects of the issuer, 3) its intent to sell and whether it is more likely than not that the Company would be required to sell those securities before the anticipated recovery of the amortized cost basis, and 4) for debt securities, the recovery of contractual principal and interest. For securities that the Company does not expect to sell, or it is not more likely than not it will be required to sell prior to recovery of its amortized cost basis, the credit component of an OTTI is recognized in earnings and the non-credit component is recognized in OCI. For securities that the Company does expect to sell, or it is more likely than not that it will be required to sell prior to recovery of its amortized cost basis, both the credit and non-credit component of an OTTI are recognized in earnings. Subsequent to recognition of OTTI, an increase in expected cash flows is recognized as a yield adjustment over the remaining expected life of the security based on an evaluation of the nature of the increase. Nonmarketable equity securities include stock acquired for regulatory purposes, such as Federal Home Loan Bank stock and Federal Reserve Bank stock. These securities are accounted for at amortized cost, evaluated for impairment at least quarterly, and included in "other assets". Gains or losses on securities sold are recorded on the trade date, using the specific identification method.
Loans Held for Sale	LOANS HELD FOR SALE Loans and loan commitments which the Company does not have the intent and ability to hold for the foreseeable future or until maturity or payoff are classified as loans held for sale at the time of origination or acquisition. Subsequent to origination or acquisition, if the Company no longer has the intent or ability to hold a loan for the foreseeable future, generally a decision has been made to sell the loan, and it is classified within loans held for sale. Unless the fair value option has been elected at origination or acquisition, loans classified as held for sale are carried at the lower of cost or fair value. Amortization/accretion of remaining unamortized net deferred loan fees or costs and discounts or premiums (if applicable) ceases when a loan is classified as held for sale. Loans held for sale primarily consist of fixed rate single-family residential mortgage loans originated and committed to be sold in the secondary market. Mortgage loans originated and held for sale are recorded at fair value under the fair value option, unless otherwise noted. For mortgage loans for which the Company has elected the fair value option, gains and losses are included in mortgage income. For any other loans held for sale, net unrealized losses, if any, are recognized through a valuation allowance that is recorded as a charge to non-interest income. See Note 20 for further discussion of the determination of fair value for loans held for sale. In most cases, loans in this category are sold within thirty days and are generally sold with the mortgage servicing rights released. Buyers generally have recourse to return a purchased loan or request reimbursement for the loan premium or servicing rights under limited circumstances. Recourse conditions may include prepayment, payment default, breach of representations or warranties, and documentation deficiencies. During 2016 and 2015, an insignificant number of loans were returned to the Company. At December 31, 2016 and 2015, the recorded repurchase liability associated with transferred loans was not material.
Loans	LOANS Legacy (Loans originated or renewed and underwritten by the Company) The Company originates mortgage, commercial, and consumer loans for customers. Loans that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at the unpaid principal balances, less the ALL, charge-offs, and unamortized net loan origination fees and direct costs, except for loans carried at fair value. Interest income is accrued as earned over the term of the loans based on the principal balance outstanding. Loan origination fees, net of certain direct origination costs, are deferred and recognized as an adjustment of the related loan yield. Acquired (Loans acquired through Business Combinations) Acquired loans are recorded at fair value on the acquisition date in accordance with ASC Topic 820, Fair Value Measurement , consistent with the exit price concept on the date of acquisition. Credit risk assumptions and any resulting credit discounts are included in the determination of fair value. Therefore, an ALL is not recorded at the acquisition date. The determination of fair value includes estimates related to discount rates, expected prepayments, and the amount and timing of undiscounted expected principal, interest, and other cash flows. Acquired loans are evaluated at acquisition and classified as purchased impaired (“acquired impaired”) or purchased non-impaired (“acquired non-impaired”). Purchased impaired loans reflect credit deterioration since origination to the extent that it is probable at the time of acquisition that the Company will be unable to collect all contractually required payments. At the time of acquisition, purchased impaired loans are accounted for individually or aggregated into loan pools with similar characteristics, which include: • whether the loan is performing according to contractual terms at the time of acquisition, • the loan type based on regulatory reporting guidelines, namely whether the loan was a mortgage, consumer, or commercial loan, • the nature of collateral, • the interest rate type, whether fixed or variable rate, and • the loan payment type, primarily whether the loan is amortizing or interest-only. From these pools, the Company uses certain loan information, including outstanding principal balance, estimated expected losses, weighted average maturity, weighted average term to re-price (if a variable rate loan), weighted average margin, and weighted average interest rate to estimate the expected cash flow for each loan pool. For purchased impaired loans, expected cash flows at the acquisition date in excess of the fair value of loans are recorded as interest income over the life of the loans using a level yield method if the timing and amount of future cash flows is reasonably estimable. For purchased non-impaired loans, the difference between the fair value and unpaid principal balance of the loan at acquisition, referred to as a purchase premium or discount, is amortized or accreted to income over the estimated life of the loans as an adjustment to yield. Subsequent to acquisition, the Company performs cash flow re-estimations at least quarterly for each purchased impaired loan and/or loan pool. Increases in estimated cash flows above those expected at acquisition are recognized on a prospective basis as interest income over the remaining life of the loan and/or pool. Decreases in expected cash flows subsequent to acquisition generally result in recognition of a provision for credit loss. The measurement of cash flows involves several assumptions and judgments (i.e., prepayments, default rates, loss severity, etc.). All of these factors are inherently subjective and significant changes in the cash flow estimations can result over the life of the loan. Classification The Company’s loan portfolio is disaggregated into portfolio segments for purposes of determining the ACL. The Company’s portfolio segments include commercial, residential mortgage, and consumer and other loans, bifurcated between legacy and acquired. The Company further disaggregates each commercial, residential mortgage, and consumer and other loans portfolio segment into classes for purposes of monitoring and assessing credit quality based on certain risk characteristics. Classes within the commercial loan portfolio segment include commercial real estate-construction, commercial real estate-other, commercial and industrial, and energy-related. Classes within the consumer and other loans portfolio segment include consumer-home equity, consumer-indirect automobile, consumer-credit card, and consumer-other.
Troubled Debt Restructurings	Troubled Debt Restructurings The Company periodically grants concessions to its customers in an attempt to protect as much of its investment as possible and minimize risk of loss. These concessions may include restructuring the terms of a loan to alleviate the burden of the customer’s near-term cash requirements. In order to be classified as a TDR, the Company must conclude that the restructuring constitutes a concession and the customer is experiencing financial difficulties. The Company defines a concession to the customer as a modification of existing terms for economic or legal reasons that it would otherwise not consider. The concession is either granted through an agreement with the customer or is imposed by a court or law. Concessions include modifying original loan terms to reduce or defer cash payments required as part of the loan agreement, including but not limited to: • a reduction of the stated interest rate for the remaining original life of the loan, • extension of the maturity date or dates at a stated interest rate lower than the current market rate for new loans with similar risk characteristics, • reduction of the face amount or maturity amount of the loan as stated in the agreement, or • reduction of accrued interest receivable on the loan. In its determination of whether the customer is experiencing financial difficulties, the Company considers numerous indicators, including, but not limited to: • whether the customer is currently in default on its existing loan(s), or is in an economic position where it is probable the customer will be in default on its loan(s) in the foreseeable future without a modification, • whether the customer has declared or is in the process of declaring bankruptcy, • whether there is substantial doubt about the customer’s ability to continue as a going concern, • whether, based on its projections of the customer’s current capabilities, the Company believes the customer’s future cash flows will be insufficient to service the loan, including interest, in accordance with the contractual terms of the existing agreement for the foreseeable future, and • whether, without modification, the customer cannot obtain sufficient funds from other sources at an effective interest rate equal to the current market rate for a similar loan for a non-troubled debtor. If the Company concludes that both a concession has been granted and the customer is experiencing financial difficulties, the Company identifies the loan as a TDR. All TDRs are considered impaired loans.
Non-accrual and Past Due Loans (Including Loan Charge-offs)	NON-ACCRUAL AND PAST DUE LOANS (INCLUDING LOAN CHARGE-OFFS) Loans are generally considered past due when contractual payments of principal and interest have not been received within 30 days from the contractual due date. Residential mortgage loans are considered past due when contractual payments have not been received for two consecutive payment dates. Legacy and purchased non-impaired loans are placed on non-accrual status when any of the following occur: 1) the loan is maintained on a cash basis because of deterioration in the financial condition of the borrower; 2) collection of the full contractual amount of principal or interest is not expected (even if the loan is currently paying as agreed); 3) when principal or interest has been in default for a period of 90 days or more, unless the loan is both well secured and in the process of collection; or 4) the borrower has filed or is likely to file bankruptcy. Factors considered in determining the collection of the full contractual amount of principal or interest include assessment of the borrower’s cash flow, valuation of underlying collateral, and the ability and willingness of guarantors to provide credit support. Certain commercial loans are also placed on non-accrual status when payment is not past due and full payment of principal and interest is expected, but we have doubt about the borrower’s ability to comply with existing repayment terms. Consideration will be given to placing a loan on non-accrual due to the deterioration of the debtor’s repayment ability, the repayment of the loan becoming dependent on the liquidation of collateral, an existing collateral deficiency, the loan being classified as "Doubtful" or "Loss", the client filing for bankruptcy, and/or foreclosure being initiated. Regarding all classes within the C&I and CRE portfolios, the determination of a borrower’s ability to make the required principal and interest payments is based on an examination of the borrower’s current financial statements, industry, management capabilities, and other qualitative measures. Purchased impaired loans are placed on non-accrual status when the Company cannot reasonably estimate cash flows on a loan or loan pool. Legacy and purchased non-impaired loans are evaluated for potential charge-off in accordance with the parameters discussed in the following paragraph or when the loan is placed on non-accrual status, whichever is earlier. Loans within the commercial portfolio (except for purchased impaired) are generally evaluated for charge-off at 90 days past due, unless both well-secured and in the process of collection. Closed and open-end residential mortgage and consumer loans (except for purchased impaired) are evaluated for charge-off no later than 120 days past due. Any outstanding loan balance in excess of the fair value of the collateral less costs to sell is charged-off no later than 120 days past due for loans secured by real estate. For non-real estate secured loans, in lieu of charging off the entire loan balance, loans may be written down to the fair value of the collateral less costs to sell if repossession of collateral is assured and in process. The accrual of interest, as well as the amortization/accretion of any remaining unamortized net deferred fees or costs and discount or premium, is discontinued at the time the loan is placed on non-accrual status. All accrued but uncollected interest for loans that are placed on non-accrual status is reversed through interest income. Cash receipts received on non-accrual loans are generally applied against principal until the loan has been collected in full, after which time any additional cash receipts are recognized as interest income (i.e., cost recovery method). However, interest may be accounted for under the cash-basis method as long as the remaining recorded investment in the loan is deemed fully collectible. Loans are returned to accrual status when the borrower has demonstrated a capacity to continue payment of the debt (generally a minimum of six months of payment history) and collection of contractually required principal and interest associated with the debt is reasonably assured. At such time, the accrual of interest and amortization/accretion of any remaining unamortized net deferred fees or costs and discount or premium shall resume. Any interest income which was applied to the principal balance shall not be reversed and subsequently will be recognized as an adjustment to yield over the remaining life of the loan.
Impaired Loans	IMPAIRED LOANS For all classes within the commercial portfolio, all loans with an outstanding commitment balance above a specific threshold are evaluated on a quarterly basis for potential impairment. Generally, residential mortgage and consumer loans within any class are not individually evaluated on a regular basis for impairment. All TDRs, regardless of the outstanding balance amount or portfolio classification, and all purchased impaired loans are considered to be impaired. A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal and/or interest when due, according to the contractual terms of the loan agreement. Factors considered by management in determining impairment include payment status, collateral value, and the likelihood of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired. Impairment losses are measured on a loan-by-loan basis for commercial and certain residential mortgage or consumer loans, based on either the present value of expected future cash flows discounted at the loan’s effective interest rate, the loan’s observable market price, or the fair value of the collateral if the loan is collateral-dependent. This measurement requires significant judgment and use of estimates, and the actual loss ultimately recognized by the Company may differ significantly from the estimates.
Allowance For Credit Losses	ALLOWANCE FOR CREDIT LOSSES The Company maintains the ACL at a level that management believes appropriate to absorb estimated probable credit losses incurred in the loan portfolios (including unfunded commitments) as of the consolidated balance sheet date. The ACL consists of the allowance for loan losses (contra asset) and the reserve for unfunded commitments (liability). The manner in which the ACL is determined is based on 1) the accounting method applied to the underlying loans and 2) whether the loan is required to be measured for impairment. The Company delineates between loans accounted for under the contractual yield method, legacy and purchased non-impaired loans, and purchased impaired loans. Further, for legacy and acquired non-impaired loans, the Company attributes portions of the ACL to loans and loan commitments that it measures individually, and groups of homogeneous loans and loan commitments that it measures collectively for impairment. Determination of the appropriate ACL involves a high degree of complexity and requires significant judgment regarding the credit quality of the loan portfolio. Several factors are taken into consideration in the determination of the overall ACL, including a qualitative component. These factors include, but are not limited to, the overall risk profiles of the loan portfolios, net charge-off experience, the extent of impaired loans, the level of non-accrual loans, the level of 90 days past due loans, the value of collateral, the ability to monetize guarantor support, and the overall percentage level of the allowance relative to the loan portfolio, amongst other factors. The Company also considers overall asset quality trends, changes in lending practices and procedures, trends in the nature and volume of the loan portfolio, including the existence and effect of any portfolio concentrations, changes in experience and depth of lending staff, the Company’s legal, regulatory and competitive environment, national and regional economic trends, data availability and applicability that might impact the portfolio or the manner in which it estimates losses, and risk rating accuracy and risk identification. The allowance for loan losses for all impaired loans (excluding purchased impaired) is determined on an individual loan basis, considering the facts and circumstances specific to each borrower. The allowance is based on the difference between the recorded investment in the loan and generally either the estimated net present value of projected cash flows or the estimated value of the collateral associated with the loan, if the loan is deemed collateral-dependent. For non-impaired loans (excluding purchased impaired), the allowance for loan losses is calculated based on pools of loans with similar characteristics. The pool-level allowance is calculated through the application of PD (i.e., probability of default) and LGD (i.e., loss given default) factors for each individual loan. PDs and LGDs are determined based on historical default and loss information for similar loans. For purposes of establishing estimated loss percentages for pools of loans that share common risk characteristics, the Company’s loan portfolio is segmented by various loan characteristics including loan type, risk rating (commercial), Vantage or FICO score (residential mortgage and consumer), past due status (residential mortgage and consumer) and call report code. The default and loss information is measured over an appropriate period for each loan pool and adjusted as deemed appropriate. Qualitative adjustments are incorporated into the pool-level analysis to accommodate for the imprecision of certain assumptions and uncertainties inherent in the calculation. See the "Loans" section of this Footnote for discussion of the determination of the ACL for purchased impaired loans. Certain inherent, but unconfirmed losses are probable within the loan portfolio. The Company’s current methodology for determining the level of inherent losses is based on historical loss rates, current credit grades, specific allocation, and other qualitative adjustments. In a stable or deteriorating credit environment, heavy reliance on historical loss rates and the credit grade rating process results in model-derived reserves that tend to slightly lag behind portfolio deterioration. Similar lags can occur in an improving credit environment whereby required reserves can lag slightly behind portfolio improvement. Given these and other model limitations, qualitative adjustment factors may be incremental or decremental to the quantitative model results. In periods prior to 2015, the Company estimated incurred losses on its Exploration and Production and its Oil Field Services portfolios as an aggregate portfolio. Beginning in 2015, as the performance of these two portfolios began to diverge, the Company disaggregated the analysis of incurred losses within these portfolios, which included modifying its LGD estimates for the portfolios to more closely align with published historical industry data and other factors. Absent this change, the Company would have recorded an additional $10.0 million , or 17 cents per share, in provision expense for the year ended December 31, 2015. The reserve for unfunded commitments is determined using similar methodologies described above for non-impaired loans. The loss factors used in the reserve for unfunded commitments are equivalent to the loss factors used in the allowance for loan losses, while also considering utilization of unused commitments.
FDIC Loss Share Receivable	FDIC LOSS SHARE RECEIVABLE The Company entered into or assumed arrangements with the FDIC which obligated the FDIC to reimburse the Company for losses on certain loans associated with FDIC-assisted transactions. The indemnification assets were recorded at fair value as of the acquisition dates based on estimated cash flows to be received over the expected life of the acquired assets, not to exceed the term of the indemnification agreements. Effective as of December 20, 2016, the Company entered into an agreement with the FDIC to terminate the Company’s twelve loss share agreements ahead of their contractual maturities. Under the terms of the agreement, all rights and obligations of the Company and FDIC have been resolved and completed. The Company received a net payment of $6.5 million from the FDIC as consideration for termination of the loss share agreements and subsequently derecognized the remaining FDIC indemnification asset of $20.4 million , along with other transaction related-adjustments (including tax impacts), resulting in a net loss of $11.2 million .
Premises and Equipment, and Software	PREMISES AND EQUIPMENT Land is carried at cost. Buildings, furniture, fixtures, and equipment are carried at cost, less accumulated depreciation computed on a straight-line basis over the estimated useful lives of 10 to 40 years for buildings and related improvements and generally 3 to 20 years for furniture, fixtures, and equipment. Leasehold improvements are amortized over the lease term, including any renewal periods that are reasonably assured, or the asset’s useful life, whichever is shorter. Premises and equipment are evaluated for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. SOFTWARE Software is amortized on a straight-line basis over its estimated useful life. The estimated useful life of software is generally three years , but can vary depending on the specific facts and circumstances. Software is evaluated for impairment whenever events or changes in circumstances indicate that the carrying amount of the software may not be recoverable.
Goodwill and Other Intangible Assets	GOODWILL AND OTHER INTANGIBLE ASSETS Goodwill Goodwill represents the excess of the consideration paid in a business combination over the fair value of the identifiable net assets acquired. Goodwill is not amortized, but is assessed for potential impairment at a reporting unit level on an annual basis, as of October 1 st , or whenever events or changes in circumstances indicate that it is more likely than not the fair value of a reporting unit is less than its respective carrying amount. As part of its testing, the Company may elect to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If the results of the qualitative assessment indicate that more likely than not a reporting unit’s fair value is less than its carrying amount, the Company determines the fair value of the respective reporting unit (through the application of various quantitative valuation methodologies ) relative to its carrying amount to determine whether quantitative indicators of potential impairment are present (i.e., Step 1). The Company may also elect to bypass the qualitative assessment and begin with Step 1. If the results of Step 1 indicate that the fair value of the reporting unit may be below its carrying amount, the Company determines the fair value of the reporting unit’s assets and liabilities, considering deferred taxes, and then measures impairment loss by comparing the implied fair value of goodwill with the carrying amount of that goodwill (i.e., Step 2). Title Plant Costs incurred to construct a title plant, including the costs incurred to obtain, organize, and summarize historical information, are capitalized until the title plant can be used to perform title searches. A purchased title plant, including a purchased undivided interest in a title plant, is recorded at cost at the date of acquisition. For a title plant acquired separately or as part of a business acquisition, cost is measured as the fair value of the consideration paid. Capitalized costs of a title plant are not depreciated or charged to income unless circumstances indicate that the carrying amount of the title plant has been impaired. Impairment indicators include a change in legal requirements or statutory practices, identification of obsolescence, or abandonment of the title plant, among other indicators. Capitalized storage and retrieval costs (e.g., costs to convert from one storage retrieval system to another or to modernize the storage and retrieval systems) incurred after a title plant is operational are charged to expense in a systematic and rational manner. Title plant is recorded within "other assets" on the Company’s consolidated balance sheets. Intangible assets subject to amortization The Company’s acquired intangible assets that are subject to amortization include (amongst other ancillary intangibles described in Note 10) core deposit intangibles, amortized on a straight-line or accelerated basis, and a customer relationship intangible asset, amortized on an accelerated basis, over average lives not to exceed 10 years. The Company reviews intangible assets for impairment whenever events or changes in circumstances indicate that their carrying amounts may not be recoverable. Impairment is identified if the sum of the undiscounted estimated future cash flows is less than the carrying value of the asset. Intangible assets are recorded within "other assets" on the Company’s consolidated balance sheets.
Other Real Estate Owned	OTHER REAL ESTATE OWNED Other real estate owned includes all real estate, other than bank premises used in bank operations, owned or controlled by the Company, including real estate acquired in settlement of loans. Properties are initially recognized at the recorded investment of the loan (which is the pro-rata carrying value of loans accounted for in accordance with ASC Topic 310-30, Receivables - Loans and Debt Securities Acquired with Deteriorated Credit Quality ) or at estimated fair value less costs to sell, whichever is less, generally when the Company has received physical possession (legal title is not required for non-consumer residential property). The amount by which the recorded investment of the loan exceeds the fair value less costs to sell of the property is charged to the ALL. Subsequent to foreclosure, the assets are carried at the lower of cost or fair value less costs to sell. Former bank properties transferred to OREO are recorded at the lower of cost or market. Subsequent declines in the fair value of other real estate are recorded as adjustments to the carrying amount through a valuation allowance. Revenue and expenses from operations, gain or loss on sale, and changes in the valuation allowance are included in net expenses from foreclosed assets. The Company included property write-downs of $3.4 million and $4.0 million in earnings for the years ended December 31, 2016 and 2015, respectively. OREO is recorded within "other assets" on the Company’s consolidated balance sheets.
Derivative Financial Instruments	DERIVATIVE FINANCIAL INSTRUMENTS The Company enters into various derivative financial instruments to manage interest rate risk, asset sensitivity, and other exposures such as liquidity and credit risk, as well as to facilitate customer transactions. The primary types of derivatives utilized by the Company for its risk management strategies include interest rate swap agreements, interest rate lock commitments, forward sales commitments, and written and purchased options. All derivative instruments are recognized on the consolidated balance sheets as "other assets" or "other liabilities" at fair value, regardless of whether a right of offset exists. Changes in the fair value (i.e., gains or losses) of a derivative instrument are recorded based on whether it has been designated and qualifies as part of a hedging relationship. Interest rate swap and foreign exchange contracts are entered into by the Company to allow its commercial customers to manage their exposure to market rate fluctuations. To mitigate the Company's exposure to the rate risk associated with customer contracts, offsetting derivative positions are entered into with reputable counterparties. The Company manages its credit risk, or potential risk of default, from the customer contracts through credit limit approval and monitoring procedures. These contracts are not designated for hedge accounting (i.e., treated as economic hedges). Derivatives Designated in Hedging Relationships For cash flow hedges, the effective portion of the gain or loss related to the derivative instrument is initially reported as a component of OCI and subsequently reclassified into earnings when the forecasted transaction affects earnings or when the hedge is terminated. The ineffective portion of the gain or loss, if any, is reported in earnings immediately, in either "other income" or "other expense", respectively. In applying hedge accounting for derivatives (ASC Topic 815-30 Derivatives and Hedging - Cash Flow Hedges ), the Company establishes and documents a method for assessing the effectiveness of the hedging derivative and a measurement approach for determining the ineffective aspect of the hedge upon the inception of the hedge. Derivatives Not Designated in Hedging Relationships For derivative instruments that are not designated as hedging instruments, changes in the fair value of the derivatives are recognized in earnings immediately. Common Types of Derivatives Interest rate swap agreements Interest rate swaps are agreements to exchange interest payments based upon notional amounts. The exchange of payments typically involves paying a fixed rate and receiving a variable rate or vice versa. As part of its activities to manage interest rate risk (i.e., the exposure to the variability of future cash flows or other forecasted transactions due to fluctuating market rates), the Company enters into interest rate contracts, which typically include interest rate swap agreements. The Company primarily utilizes these instruments, which the Company designates as cash flow hedges, to convert a portion of its variable-rate loans or debt to a fixed rate. Interest rate lock commitments The Company enters into commitments to originate mortgage loans intended for sale whereby the interest rate on the prospective loan is determined prior to funding (“rate lock”). A rate lock is provided to a borrower, subject to conditional performance obligations, for a specified period of time that typically does not exceed 60 days. Rate lock commitments on mortgage loans that are intended to be sold are recognized as derivatives. Accordingly, such commitments are recorded at fair value as derivative assets or liabilities, with changes in fair value recorded in mortgage income on the consolidated statements of comprehensive income. Forward sales commitments The Company uses forward sales commitments to protect the value of its rate locks and mortgage loans held for sale from changes in interest rates and pricing between the origination of the rate lock and sale of these loans, as changes in interest rates have the potential to cause a decline in value of rate locks and mortgage loans included in the held for sale portfolio. These commitments are recognized as derivatives and recorded at fair value as derivative assets or liabilities, with changes in fair value recorded in mortgage income on the consolidated statements of comprehensive income. Equity-indexed certificates of deposit IBERIABANK offers its customers a certificate of deposit that provides the purchaser a guaranteed return of principal at maturity plus a potential return, which allows IBERIABANK to identify a known cost of funds. The rate of return is based on the performance of a group of publicly traded stocks that represent a variety of industry segments. Because it is based on an equity index, the rate of return represents an embedded derivative that is not clearly and closely related to the host instrument and is to be accounted for separately. Accordingly, the certificate of deposit is separated into two components: a zero coupon certificate of deposit (the host instrument) and a written option purchased by the depositor (an embedded derivative). The discount on the zero coupon deposit is amortized over the life of the deposit, and the written option is carried at fair value on the Company’s consolidated balance sheets, with changes in fair value recorded through earnings. IBERIABANK offsets the risks of the written option by purchasing an option with terms that mirror the written option, which is also carried at fair value on the Company’s consolidated balance sheets.
Off-Balance Sheet Credit-Related Financial Instruments	OFF-BALANCE SHEET CREDIT-RELATED FINANCIAL INSTRUMENTS In the ordinary course of business, the Company executes various commitments to extend credit, including commitments under commercial construction arrangements, commercial and home equity lines of credit, credit card arrangements, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded on the funding date.
Transfers of Financial Assets	TRANSFERS OF FINANCIAL ASSETS Transfers of financial assets, or portions thereof which meet the definition of a participating interest, are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when 1) the assets have been legally isolated from the Company, 2) the transferee obtains the right, free of conditions that constrain it from taking advantage of that right and provide the Company with more than a trivial benefit, to pledge or exchange the transferred assets, and 3) the Company does not maintain effective control over the transferred assets. Should the transfer not satisfy all three criteria, the transaction is recorded as a secured borrowing. If the transfer is accounted for as a sale, the transferred assets are derecognized from the Company’s balance sheet and a gain or loss on sale is recognized. If the transfer is accounted for as a secured borrowing, the transferred assets remain on the Company’s balance sheet and the proceeds from the transaction are recognized as a liability. Servicing Rights The Company recognizes the rights to service mortgage and other loans as separate assets, which are recorded in "other assets" in the consolidated balance sheets, when purchased or when servicing is contractually separated from the underlying loans by sale with servicing rights retained. For loan sales with servicing retained, a servicing right (generally an asset) is recorded at fair value for the right to service the loans sold. All servicing rights are identified by class and subsequently accounted for under the amortization method.
Income Taxes	INCOME TAXES The Company and all subsidiaries file a consolidated Federal income tax return on a calendar year basis. The Company files income tax returns in the U.S. Federal jurisdiction and various state and local jurisdictions through IBERIABANK Corporation (Parent), IBERIABANK, IMC, LTC, and their subsidiaries. In lieu of Louisiana state income tax, IBERIABANK is subject to the Louisiana bank shares tax, portions of which are included in both "non-interest expense" and "income tax expense" in the Company’s consolidated statements of comprehensive income. With few exceptions, the Company is no longer subject to U.S. federal, state or local income tax examinations for years before 2012. Deferred income tax assets and liabilities are determined using the liability (or balance sheet) method. Under this method, the net deferred tax asset or liability is determined based on the tax effects of the temporary differences between the book and tax bases of the various balance sheet assets and liabilities and gives current recognition to changes in tax rates and laws. The measurement of deferred tax assets is reduced, if necessary, by the amount of any tax benefits that, based on available evidence, are not expected to be realized. The Company recognizes interest and penalties accrued related to unrecognized tax benefits, if applicable, in "non-interest expense".
Share-based Compensation Plans	SHARE-BASED COMPENSATION PLANS The Company issues stock options, restricted stock awards, restricted share units, performance units, and phantom awards under various plans to directors, officers, and other key employees. Compensation cost for all awards is recognized on a straight-line basis over the requisite service period, which is generally the vesting period, taking into account retirement eligibility. For service awards with graded vesting, the Company recognizes compensation cost on a straight-line basis. The majority of the Company's share-based awards qualify for equity accounting and contain service conditions. Under equity accounting, the fair value of the award is measured at the grant date and not subsequently remeasured. For awards that contain a market condition, the Company includes the market condition in the determination of the grant date fair value of the award. Compensation cost for an award with a market condition is recognized regardless of whether the market condition is satisfied, assuming the requisite service is met. The Company does not include performance conditions in the determination of the grant date fair value of the award. Compensation cost for an award with a performance condition is not recognized if the performance condition is not satisfied. Phantom awards and performance units, accounted for as liability awards, are remeasured at each reporting period based on their fair value until the date of settlement. Compensation cost for each reporting period until settlement is based on the change (or a portion of the change, depending on the percentage of the requisite service that has been rendered at the reporting date) in the fair value of the phantom award and performance unit for each reporting period. Compensation expense relating to share-based awards is recognized in net income as part of “salaries and employee benefits” on the consolidated statements of comprehensive income for employees and “professional services” for non-employee directors. The exercise price for the options granted by the Company is not less than the fair market value of the underlying stock at the grant date.
Earnings Per Common Share	EARNINGS PER COMMON SHARE Basic earnings per share represents income available to common shareholders divided by the weighted average number of common shares outstanding during the period. Diluted earnings per share reflects additional common shares that would have been outstanding if dilutive potential common shares, in the form of stock options or restricted stock units, had been issued, as well as any adjustment to income that would result from the assumed issuance. Participating common shares issued by the Company relate to unvested outstanding restricted stock awards, the earnings allocated to which are used in determining income available to common shareholders under the two-class method. The two-class method allocates earnings for the period between common shareholders and other participating securities holders. The participating awards receiving dividends are allocated the same percentage of income as if they were outstanding shares.
Share Repurchases	SHARE REPURCHASES Repurchases of the Company’s common stock are recorded at cost. Effective January 1, 2015, companies incorporated in Louisiana became subject to the Louisiana Business Corporation Act (which replaced the Louisiana Business Corporation Law). Provisions of the Louisiana Business Corporation Act eliminated the concept of treasury stock and provide that shares reacquired by a company are to be treated as authorized but unissued shares. As a result of this change in law, for the consolidated financial statements beginning with the quarterly period ended March 31, 2015, the Company classifies shares previously classified as treasury stock as a reduction to issued shares of common stock, and accordingly, adjusts the stated value of common stock and paid-in-capital.
Comprehensive Income	COMPREHENSIVE INCOME Accounting principles generally require that recognized revenue, expenses, gains, and losses be included in net income. Although certain changes in assets and liabilities, such as unrealized gains and losses on available for sale securities and cash flow hedges, are reported as a separate component of the shareholders’ equity section of the consolidated balance sheets, such items, along with net income, are components of comprehensive income.
Fair Value Measurements	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. The Company estimates fair value based on the assumptions market participants would use when selling an asset or transferring a liability and characterizes such measurements within the fair value hierarchy based on the inputs used to develop those assumptions and measure fair value. The hierarchy requires the Company to maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows: • Level 1 - Quoted prices in active markets for identical assets or liabilities. • Level 2 - Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. • Level 3 - Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. This includes certain pricing models, discounted cash flow methodologies, and similar techniques that use significant unobservable inputs. A description of the valuation methodologies used for instruments measured at fair value follows, as well as the classification of such instruments within the valuation hierarchy. The descriptions below are exclusive of assets or liabilities acquired in business combinations, as all such instruments are required to initially be measured at fair value. Cash and cash equivalents The carrying amounts of cash and cash equivalents approximate their fair value. Investment securities Securities are classified within Level 1 where quoted market prices are available in an active market. Inputs include securities that have quoted prices in active markets for identical assets. If quoted market prices are unavailable, fair value is estimated using quoted prices of securities with similar characteristics, at which point the securities are classified within Level 2 of the hierarchy. Mortgage loans held for sale Mortgage loans originated and held for sale are recorded at fair value under the fair value option, unless otherwise noted. When determining the fair value of loans held for sale, the Company obtains quotes or bids on these loans directly from the purchasing financial institutions (Level 2). Loans The fair values of mortgage loans are estimated based on present values using entry-value rates (the interest rate that would be charged for a similar loan to a borrower with similar risk at the indicated balance sheet date) at December 31, 2016 and 2015, weighted for varying maturity dates. Other loans are valued based on present values using entry-value interest rates at December 31, 2016 and 2015 applicable to each category of loans, which are classified within Level 3 of the hierarchy. Impaired loans Loans are measured for impairment using the methods permitted by ASC Topic 310, Receivables . Fair value measurements are used in determining impairment using either the loan’s observable market price (Level 1), if available, or the fair value of the collateral, if the loan is collateral-dependent (Level 3). Fair value of the collateral is determined by appraisals or independent valuation. Measuring the impairment of loans using the present value of expected future cash flows, discounted at the loan’s effective interest rate, is not considered a fair value measurement under GAAP as the interest rate used to discount the cash flows does not necessarily reflect current credit or market conditions for such loans. Other real estate owned Fair values of OREO are determined by sales agreement or appraisal and costs to sell are based on estimation per the terms and conditions of the sales agreement or amounts commonly used in real estate transactions. Inputs include appraisal values on the properties or recent sales activity for similar assets in the property’s market, and thus OREO measured at fair value is classified within Level 3 of the hierarchy. Derivative financial instruments Fair values of interest rate swaps, interest rate locks, forward sales commitments, and written and purchased options are estimated using prices of financial instruments with similar characteristics and thus are classified within Level 2 of the fair value hierarchy. Deposits The fair values of NOW accounts, money market deposits and savings accounts are the amounts payable on demand at the reporting date. Certificates of deposit are valued using a discounted cash flow model based on the weighted-average rate at December 31, 2016 and 2015 for deposits with similar remaining maturities. The fair value of the Company’s deposits are categorized within Level 3 of the fair value hierarchy. Short-term borrowings The carrying amounts of short-term borrowings maturing within ninety days approximate their fair values. Long-term debt The fair values of long-term debt are estimated using discounted cash flow analyses based on the Company’s current incremental borrowing rates for similar types of borrowing arrangements. The fair value of the Company’s long-term debt is categorized within Level 3 of the fair value hierarchy. Off-balance sheet items The Company has outstanding commitments to extend credit and standby letters of credit. These off-balance sheet financial instruments are generally exercisable at the market rate prevailing at the date the underlying transaction will be completed. At December 31, 2016 and 2015, the fair value of guarantees under commercial and standby letters of credit was not material.
Recent Accounting Pronouncements	RECENT ACCOUNTING PRONOUNCEMENTS ASU No. 2014-09 In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers , which implements a common revenue standard and clarifies the principles used for recognizing revenue. The amendments in the ASU clarify that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. As part of that principle, the entity should identify the contract(s) with the customer, identify the performance obligation(s) of the contract, determine the transaction price, allocate that transaction price to the performance obligation(s), and then recognize revenue when or as the entity satisfies the performance obligation(s). The amendments also provide additional guidance/principles associated with gross vs. net presentation (i.e., principal versus agency considerations). The amendments in ASU No. 2014-09 will be effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that annual reporting period. The amendments will be applied through the election of one of two retrospective methods. The Company intends to adopt the amendments beginning January 1, 2018 through the modified-retrospective transition method. Based on the Company’s preliminary scoping, walkthroughs, and contract reviews, it does not expect to recognize a significant cumulative adjustment to equity upon implementation of the standard. Further, the Company does not expect a significant impact to the Company’s consolidated statements of comprehensive income or consolidated balance sheets from either a presentation or timing perspective, but is still analyzing some contracts (e.g., card interchange and rewards). The Company does anticipate additional disclosures will be presented in the notes to the consolidated financial statements following adoption. ASU No. 2015-02 In February 2015, the FASB issued ASU No. 2015-02, Consolidation - Amendments to the Consolidation Analysis , which changes the analysis that a reporting entity must perform to determine whether it should consolidate certain types of legal entities. The amendments in the guidance: 1) modify the evaluation of whether limited partnerships and similar legal entities are variable interest entities or voting interest entities, 2) eliminate the presumption that a general partner should consolidate a limited partnership, 3) affect the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships, and 4) provide a scope exception from consolidation guidance for certain investment funds. The Company adopted the amendment, effective January 1, 2016, through retrospective application on all existing agreements; however, there was no resulting change to amounts reported in prior periods. Refer to Note 1 for current principles of consolidation. ASU No. 2015-05 In April 2015, the FASB issued new accounting guidance related to whether a cloud computing arrangement includes a software license (ASU No. 2015-05, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement). If a cloud computing arrangement includes a software license, the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. The Company adopted the amendment prospectively on all arrangements entered into or materially modified beginning January 1, 2016, on an individual arrangement basis. The impact of the adoption of ASU 2015-05 was not material to the Company’s consolidated financial statements. ASU No. 2016-01 In January 2016, the FASB issued ASU No. 2016-01, Financial Statements - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The amendments will not change the guidance for classifying and measuring investments in debt securities or loans; however, the ASU will impact how entities measure certain equity investments, recognize changes in the fair value of financial liabilities measured under the fair value option that are attributable to instrument-specific credit risk, and disclose and present financial assets and liabilities in financial statements. Specifically, the aforementioned amendments will require measurement of equity investments at fair value, with changes recognized in net income, unless the investments qualify for the new practicability exception, the equity method of accounting, or consolidation. For financial liabilities measured using the fair value option, any change in fair value caused by a change in an entity’s own credit risk will be recognized separately in OCI, as opposed to earnings. The amendments will also require entities to present financial assets and financial liabilities separately, grouped by measurement category and form of financial asset in the statement of financial position or in the accompanying notes to the financial statements. Entities will also no longer have to disclose the methods and significant assumptions for financial instruments measured at amortized cost, but will be required to measure such instruments under the “exit price” notion for disclosure purposes. ASU No. 2016-01 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. An entity will record a cumulative-effect adjustment to beginning retained earnings as of the beginning of the first reporting period in which the guidance is adopted, with two exceptions. The amendments related to equity investments without readily determinable fair values (including disclosure requirements) will be effective prospectively. The requirement to use the exit price notion to measure the fair value of financial instruments for disclosure purposes will also be applied prospectively. The Company does not expect a significant cumulative-effect adjustment to be recorded at adoption or any significant impact to the consolidated financial statements associated with the accounting for its current equity investments. The Company does anticipate financial statement disclosures to be impacted, specifically related to financial instruments measured at amortized cost whose fair values are disclosed under the “entry price” notion, but is currently still in the process of determining the impact. ASU No. 2016-02 In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842 ). The most significant amendment to existing GAAP is the recognition of lease assets (i.e., right of use assets) and liabilities on the balance sheet for leases that are classified as operating leases by lessees. The lessor model remains similar to the current accounting model in existing GAAP. Additional amendments include, but are not limited to, the elimination of leveraged leases; modification to the definition of a lease; amendments on sale and leaseback transactions; and disclosure of additional quantitative and qualitative information. ASU 2016-02 will be effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The Company anticipates adopting the amendments on January 1, 2019. The Company is currently assessing the practical expedients it may elect at adoption, but does not anticipate the amendments will have a significant impact to the consolidated financial statements. Based on the Company’s preliminary analysis of its current portfolio, the impact to the Company’s consolidated balance sheets is estimated to result in less than a 1% increase in assets and liabilities. The adjustment to retained earnings is not expected to be material based on the transition guidance associated with current sale-leaseback agreements. The Company also anticipates additional disclosures to be provided at adoption. ASU No. 2016-09 In March 2016, the FASB issued ASU No. 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting . The amendments will require recognition of excess tax benefits and deficiencies associated with awards which vest or settle within income tax expense or benefit in the statement of comprehensive income, with the tax effects treated as discrete items in the reporting period in which they occur. The ASU further requires entities to recognize excess tax benefits regardless of whether the benefit reduces taxes payable in the current period. This will eliminate the current APIC pool concept. The amendments will also allow an accounting policy election to account for forfeitures as they occur, permit an entity to withhold up to the maximum statutory tax rates in the applicable jurisdictions while still qualifying for equity classification, and change the classification of certain cash flows associated with stock compensation. ASU 2016-09 will be effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The transition method for implementing each amendment varies. The Company expects to elect an accounting policy to account for forfeitures as they occur upon adoption. Based on the Company's current stock valuation and estimated exercise activity associated with stock options, it anticipates an insignificant reduction to income tax expense at adoption. ASU No. 2016-13 In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The amendments introduce an impairment model that is based on expected credit losses (“ECL”), rather than incurred losses, to estimate credit losses on certain types of financial instruments (e.g., loans and held-to-maturity securities), including certain off-balance sheet financial instruments (e.g., loan commitments). The ECL should consider historical information, current information, and reasonable and supportable forecasts, including estimates of prepayments, over the contractual term. Financial instruments with similar risk characteristics may be grouped together when estimating the ECL. The ASU also amends the current AFS security impairment model for debt securities. The new model will require an estimate of ECL when the fair value is below the amortized cost of the asset through the use of an allowance to record estimated credit losses (and subsequent recoveries). Non-credit related losses will continue to be recognized through OCI. In addition, the amendments provide for a simplified accounting model for purchased financial assets with a more-than-insignificant amount of credit deterioration since their origination. The initial estimate of expected credit losses would be recognized through an ALL with an offset (i.e., increase) to the cost basis of the related financial asset at acquisition. ASU 2016-13 will be effective for fiscal years beginning after December 15, 2019, including interim periods. The amendments will be applied through a modified-retrospective approach, resulting in a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective. A prospective transition approach is required for debt securities for which OTTI had been recognized before the effective date. Amounts previously recognized in AOCI as of the date of adoption that relate to improvements in cash flows expected to be collected should continue to be accreted into income over the remaining life of the asset. Recoveries of amounts previously written off relating to improvements in cash flows after the date of adoption should be recorded in earnings when received. The Company is currently evaluating the impact of the ASU on the Company’s consolidated financial statements. ASU No. 2016-15 In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments , in order to reduce current diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. ASU 2016-15 will be effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. The amendments should be applied using a retrospective transition method to each period presented. The Company is currently evaluating the impact of the ASU on the Company’s consolidated statement of cash flows. The Company is not expecting to early adopt the ASU. ASU No. 2017-01 In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business , which introduces amendments that are intended to clarify the definition of a business to assist companies and other reporting organizations with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The amendments are intended to narrow the current interpretation of a business. ASU No. 2017-01 will be effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within those periods. The amendments will be applied prospectively on or after the effective date. Early application of the amendments in this ASU is allowed for transactions, including when a subsidiary or group of assets is deconsolidated/derecognized, in which the acquisition date occurs before the issuance date or effective date of the amendments, only when the transaction has not been reported in financial statements that have been issued or made available for issuance. The Company is currently evaluating the effect of the ASU. ASU No. 2017-04 In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment, which simplifies how an entity is required to test goodwill for impairment by eliminating Step 2 from the goodwill impairment test. Therefore, any carrying amount which exceeds the reporting unit’s fair value (up to the amount of goodwill recorded) will be recognized as an impairment loss. ASU No. 2017-04 will be effective for annual reporting periods beginning after December 15, 2019, including interim reporting periods within those periods. The amendments will be applied prospectively on or after the effective date. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Based on recent goodwill impairments tests, which did not require the application of Step 2, the Company does not expect the adoption of this ASU to have an immediate impact.

Acquisition Activity (Tables)

Acquisition Activity (Tables)	12 Months Ended
	Dec. 31, 2016
Florida Bank Group, Inc.
Business Acquisition
Schedule of Business Acquisitions	Acquisition of Florida Bank Group, Inc. (Dollars in thousands) Number of Shares Amount Equity consideration Common stock issued 752,493 $ 47,497 Total equity consideration 47,497 Non-Equity consideration Cash 42,988 Total consideration paid 90,485 Fair value of net assets assumed including identifiable intangible assets 73,043 Goodwill $ 17,442
Schedule of Assets Acquired and Liabilities Assumed	(Dollars in thousands) As Acquired Fair Value Adjustments As recorded by the Company Assets Cash and cash equivalents $ 72,982 $ — $ 72,982 Investment securities 107,236 136 (1) 107,372 Loans 312,902 (5,371 ) (2) 307,531 Other real estate owned 498 (75 ) (3) 423 Core deposit intangible — 4,489 (4) 4,489 Deferred tax asset, net 18,151 8,569 (5) 26,720 Other assets 29,817 (8,949 ) (6) 20,868 Total Assets $ 541,586 $ (1,201 ) $ 540,385 Liabilities Interest-bearing deposits $ 282,417 $ 263 (7) $ 282,680 Non-interest-bearing deposits 109,548 — 109,548 Borrowings 60,000 8,598 (8) 68,598 Other liabilities 1,898 4,618 (9) 6,516 Total Liabilities $ 453,863 $ 13,479 $ 467,342 Explanation of certain fair value adjustments: (1) The amount represents the adjustment of the book value of Florida Bank Group’s investments to their estimated fair value on the date of acquisition. (2) The amount represents the adjustment of the book value of Florida Bank Group's loans to their estimated fair values based on acquisition date interest rates and expected cash flows, which includes estimates of expected credit losses inherent in the portfolio. (3) The adjustment represents the adjustment of Florida Bank Group's OREO to its estimated fair value less costs to sell on the date of acquisition. (4) The amount represents the fair value of the core deposit intangible asset created in the acquisition. (5) The amount represents the net deferred tax asset recognized on the fair value adjustments of Florida Bank Group acquired assets and assumed liabilities. (6) The amount represents the adjustment of the book value of Florida Bank Group’s property, equipment, and other assets to their estimated fair value at the acquisition date based on their appraised value. (7) The amount represents the adjustment of the book value of Florida Bank Group's time deposits to their estimated fair values at the date of acquisition. (8) The amount represents the adjustment of the book value of Florida Bank Group’s borrowings to their estimated fair value based on acquisition date interest rates and the credit characteristics inherent in the liability. (9) The amount is necessary to record Florida Bank Group's rent liability at fair value.
Old Florida Bancshares, Inc.
Business Acquisition
Schedule of Business Acquisitions	Acquisition of Old Florida Bancshares, Inc. (Dollars in thousands) Number of Shares Amount Equity consideration Common stock issued 3,839,554 $ 242,007 Total equity consideration 242,007 Non-Equity consideration Cash 11,145 Total consideration paid 253,152 Fair value of net assets assumed including identifiable intangible assets 152,375 Goodwill $ 100,777
Schedule of Assets Acquired and Liabilities Assumed	(Dollars in thousands) As Acquired Fair Value Adjustments As recorded by the Company Assets Cash and cash equivalents $ 360,688 $ — $ 360,688 Investment securities 67,209 — 67,209 Loans held for sale 5,952 — 5,952 Loans 1,073,773 (10,822 ) (1) 1,062,951 Other real estate owned 4,515 1,449 (2) 5,964 Core deposit intangible — 6,821 (3) 6,821 Deferred tax asset, net 9,490 4,388 (4) 13,878 Other assets 30,549 (7,238 ) (5) 23,311 Total Assets $ 1,552,176 $ (5,402 ) $ 1,546,774 Liabilities Interest-bearing deposits $ 1,048,765 $ 123 (6) $ 1,048,888 Non-interest-bearing deposits 340,869 — 340,869 Borrowings 1,528 — 1,528 Other liabilities 3,038 76 (7) 3,114 Total Liabilities $ 1,394,200 $ 199 $ 1,394,399 Explanation of certain fair value adjustments: (1) The amount represents the adjustment of the book value of Old Florida's loans to their estimated fair values based on acquisition date interest rates and expected cash flows, which includes estimates of expected credit losses inherent in the portfolio. (2) The adjustment represents the adjustment of Old Florida's OREO to its estimated fair value less costs to sell on the date of acquisition. (3) The amount represents the fair value of the core deposit intangible asset created in the acquisition. (4) The amount represents the net deferred tax asset recognized on the fair value adjustment of Old Florida acquired assets and assumed liabilities. (5) The amount represents the adjustment of the book value of Old Florida’s property, equipment, and other assets to their estimated fair value at the acquisition date based on their appraised value. (6) The amount represents the adjustment of the book value of Old Florida's time deposits to their estimated fair values on the date of acquisition. (7) The adjustment is necessary to record Old Florida's rent liability at fair value.
Georgia Commerce Bancshares Inc.
Business Acquisition
Schedule of Business Acquisitions	Acquisition of Georgia Commerce Bancshares, Inc (Dollars in thousands) Number of Shares Amount Equity consideration Common stock issued 2,882,357 $ 185,249 Total equity consideration 185,249 Non-Equity consideration Cash 5,015 Total consideration paid 190,264 Fair value of net assets assumed including identifiable intangible assets 103,569 Goodwill $ 86,695
Schedule of Assets Acquired and Liabilities Assumed	(Dollars in thousands) As Acquired Fair Value As recorded by Assets Cash and cash equivalents $ 51,059 $ — $ 51,059 Investment securities 135,710 (807 ) (1) 134,903 Loans held for sale 1,249 — 1,249 Loans 807,726 (15,607 ) (2) 792,119 Other real estate owned 9,795 (4,207 ) (3) 5,588 Core deposit intangible — 6,720 (4) 6,720 Deferred tax asset, net 3,603 5,452 (5) 9,055 Other assets 28,956 (657 ) (6) 28,299 Total Assets $ 1,038,098 $ (9,106 ) $ 1,028,992 Liabilities Interest-bearing deposits 658,133 176 (7) 658,309 Non-interest-bearing deposits 249,739 — 249,739 Borrowings 13,204 — 13,204 Other liabilities 4,171 — 4,171 Total Liabilities $ 925,247 $ 176 $ 925,423 Explanation of certain fair value adjustments: (1) The amount represents the adjustment of the book value of Georgia Commerce’s investments to their estimated fair value on the date of acquisition. (2) The amount represents the adjustment of the book value of Georgia Commerce's loans to their estimated fair value based on acquisition date interest rates and expected cash flows, which includes estimates of expected credit losses inherent in the portfolio. (3) The adjustment represents the adjustment of Georgia Commerce's OREO to its estimated fair value less costs to sell on the date of acquisition. (4) The amount represents the fair value of the core deposit intangible asset created in the acquisition. (5) The amount represents the net deferred tax asset recognized on the fair value adjustment of Georgia Commerce acquired assets and assumed liabilities. (6) The amount represents the adjustment of the book value of Georgia Commerce’s property, equipment, and other assets to their estimated fair value at the acquisition date based on their appraised value. (7) The amount represents the adjustment of the book value of Georgia Commerce's time deposits to their estimated fair values at the date of acquisition. There were no acquisitions during the year ended December 31, 2016.

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Available-for-sale Securities	Information pertaining to securities with gross unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous loss position, is as follows: December 31, 2016 Less Than Twelve Months Over Twelve Months Total (Dollars in thousands) Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Securities available for sale: U.S. Government-sponsored enterprise obligations $ (549 ) $ 150,554 $ — $ — $ (549 ) $ 150,554 Obligations of state and political obligations (5,207 ) 148,059 — — (5,207 ) 148,059 Mortgage-backed securities (38,667 ) 2,191,563 (2,624 ) 98,912 (41,291 ) 2,290,475 Other Securities (451 ) 36,484 (53 ) 3,850 (504 ) 40,334 Total securities available for sale $ (44,874 ) $ 2,526,660 $ (2,677 ) $ 102,762 $ (47,551 ) $ 2,629,422 Securities held to maturity: Obligations of state and political obligations $ (133 ) $ 10,602 $ — $ — $ (133 ) $ 10,602 Mortgage-backed securities (330 ) 12,288 (487 ) 10,960 (817 ) 23,248 Total securities held to maturity $ (463 ) $ 22,890 $ (487 ) $ 10,960 $ (950 ) $ 33,850 December 31, 2015 Less Than Twelve Months Over Twelve Months Total (Dollars in thousands) Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Securities available for sale: U.S. Government-sponsored enterprise obligations $ (1,214 ) $ 177,839 $ (378 ) $ 28,116 $ (1,592 ) $ 205,955 Obligations of state and political obligations (9 ) 5,765 — — (9 ) 5,765 Mortgage-backed securities (11,737 ) 1,279,914 (4,786 ) 185,215 (16,523 ) 1,465,129 Other Securities (488 ) 51,975 (9 ) 499 (497 ) 52,474 Total securities available for sale $ (13,448 ) $ 1,515,493 $ (5,173 ) $ 213,830 $ (18,621 ) $ 1,729,323 Securities held to maturity: Obligations of state and political obligations $ (9 ) $ 1,999 $ (92 ) $ 4,162 $ (101 ) $ 6,161 Mortgage-backed securities (45 ) 3,530 (731 ) 17,573 (776 ) 21,103 Total securities held to maturity $ (54 ) $ 5,529 $ (823 ) $ 21,735 $ (877 ) $ 27,264 The amortized cost and fair values of investment securities, with gross unrealized gains and losses, consist of the following: December 31, 2016 (Dollars in thousands) Amortized Gross Gross Estimated Securities available for sale: U.S. Government-sponsored enterprise obligations $ 212,662 $ 245 $ (549 ) $ 212,358 Obligations of state and political subdivisions 286,458 1,948 (5,207 ) 283,199 Mortgage-backed securities 2,888,180 4,820 (41,291 ) 2,851,709 Other securities 98,974 361 (504 ) 98,831 Total securities available for sale $ 3,486,274 $ 7,374 $ (47,551 ) $ 3,446,097 Securities held to maturity: Obligations of state and political subdivisions $ 64,726 $ 1,609 $ (133 ) $ 66,202 Mortgage-backed securities 24,490 57 (817 ) 23,730 Total securities held to maturity $ 89,216 $ 1,666 $ (950 ) $ 89,932 December 31, 2015 (Dollars in thousands) Amortized Gross Gross Estimated Securities available for sale: U.S. Government-sponsored enterprise obligations $ 252,514 $ 1,161 $ (1,592 ) $ 252,083 Obligations of state and political subdivisions 182,541 5,429 (9 ) 187,961 Mortgage-backed securities 2,272,879 8,457 (16,523 ) 2,264,813 Other securities 95,496 430 (497 ) 95,429 Total securities available for sale $ 2,803,430 $ 15,477 $ (18,621 ) $ 2,800,286 Securities held to maturity: Obligations of state and political subdivisions $ 69,979 $ 2,803 $ (101 ) $ 72,681 Mortgage-backed securities 28,949 107 (776 ) 28,280 Total securities held to maturity $ 98,928 $ 2,910 $ (877 ) $ 100,961
Held-to-maturity Securities	Information pertaining to securities with gross unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous loss position, is as follows: December 31, 2016 Less Than Twelve Months Over Twelve Months Total (Dollars in thousands) Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Securities available for sale: U.S. Government-sponsored enterprise obligations $ (549 ) $ 150,554 $ — $ — $ (549 ) $ 150,554 Obligations of state and political obligations (5,207 ) 148,059 — — (5,207 ) 148,059 Mortgage-backed securities (38,667 ) 2,191,563 (2,624 ) 98,912 (41,291 ) 2,290,475 Other Securities (451 ) 36,484 (53 ) 3,850 (504 ) 40,334 Total securities available for sale $ (44,874 ) $ 2,526,660 $ (2,677 ) $ 102,762 $ (47,551 ) $ 2,629,422 Securities held to maturity: Obligations of state and political obligations $ (133 ) $ 10,602 $ — $ — $ (133 ) $ 10,602 Mortgage-backed securities (330 ) 12,288 (487 ) 10,960 (817 ) 23,248 Total securities held to maturity $ (463 ) $ 22,890 $ (487 ) $ 10,960 $ (950 ) $ 33,850 December 31, 2015 Less Than Twelve Months Over Twelve Months Total (Dollars in thousands) Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Securities available for sale: U.S. Government-sponsored enterprise obligations $ (1,214 ) $ 177,839 $ (378 ) $ 28,116 $ (1,592 ) $ 205,955 Obligations of state and political obligations (9 ) 5,765 — — (9 ) 5,765 Mortgage-backed securities (11,737 ) 1,279,914 (4,786 ) 185,215 (16,523 ) 1,465,129 Other Securities (488 ) 51,975 (9 ) 499 (497 ) 52,474 Total securities available for sale $ (13,448 ) $ 1,515,493 $ (5,173 ) $ 213,830 $ (18,621 ) $ 1,729,323 Securities held to maturity: Obligations of state and political obligations $ (9 ) $ 1,999 $ (92 ) $ 4,162 $ (101 ) $ 6,161 Mortgage-backed securities (45 ) 3,530 (731 ) 17,573 (776 ) 21,103 Total securities held to maturity $ (54 ) $ 5,529 $ (823 ) $ 21,735 $ (877 ) $ 27,264 The amortized cost and fair values of investment securities, with gross unrealized gains and losses, consist of the following: December 31, 2016 (Dollars in thousands) Amortized Gross Gross Estimated Securities available for sale: U.S. Government-sponsored enterprise obligations $ 212,662 $ 245 $ (549 ) $ 212,358 Obligations of state and political subdivisions 286,458 1,948 (5,207 ) 283,199 Mortgage-backed securities 2,888,180 4,820 (41,291 ) 2,851,709 Other securities 98,974 361 (504 ) 98,831 Total securities available for sale $ 3,486,274 $ 7,374 $ (47,551 ) $ 3,446,097 Securities held to maturity: Obligations of state and political subdivisions $ 64,726 $ 1,609 $ (133 ) $ 66,202 Mortgage-backed securities 24,490 57 (817 ) 23,730 Total securities held to maturity $ 89,216 $ 1,666 $ (950 ) $ 89,932 December 31, 2015 (Dollars in thousands) Amortized Gross Gross Estimated Securities available for sale: U.S. Government-sponsored enterprise obligations $ 252,514 $ 1,161 $ (1,592 ) $ 252,083 Obligations of state and political subdivisions 182,541 5,429 (9 ) 187,961 Mortgage-backed securities 2,272,879 8,457 (16,523 ) 2,264,813 Other securities 95,496 430 (497 ) 95,429 Total securities available for sale $ 2,803,430 $ 15,477 $ (18,621 ) $ 2,800,286 Securities held to maturity: Obligations of state and political subdivisions $ 69,979 $ 2,803 $ (101 ) $ 72,681 Mortgage-backed securities 28,949 107 (776 ) 28,280 Total securities held to maturity $ 98,928 $ 2,910 $ (877 ) $ 100,961
Additional Information on Securities in a Continuous Loss Position	Additional information on securities that have been in a continuous loss position for over twelve months at December 31 is presented in the following table. (Dollars in thousands) 2016 2015 Number of securities Issued by Fannie Mae, Freddie Mac, or Ginnie Mae 28 40 Issued by political subdivisions — 2 Other 3 1 31 43 Amortized Cost Basis Issued by Fannie Mae, Freddie Mac, or Ginnie Mae $ 112,983 $ 236,800 Issued by political subdivisions — 4,253 Other 3,903 508 $ 116,886 $ 241,561 Unrealized Loss Issued by Fannie Mae, Freddie Mac, or Ginnie Mae $ 3,111 $ 5,895 Issued by political subdivisions — 92 Other 53 9 $ 3,164 $ 5,996
Schedule of Amortized Cost and Estimated Fair Value of Investment Securities by Maturity	The amortized cost and estimated fair value of investment securities by maturity at December 31, 2016 are presented in the following table. Securities are classified according to their contractual maturities without consideration of principal amortization, potential prepayments or call options. Accordingly, actual maturities may differ from contractual maturities. Weighted average yields are calculated on the basis of the yield to maturity based on the amortized cost of each security. Securities Available for Sale Securities Held to Maturity (Dollars in thousands) Weighted Amortized Estimated Weighted Amortized Estimated Within one year or less 2.29 % $ 15,540 $ 15,477 2.59 % $ 2,551 $ 2,570 One through five years 1.65 283,914 284,150 2.95 9,903 10,082 After five through ten years 2.25 703,768 697,829 3.07 18,181 18,569 Over ten years 2.05 2,483,052 2,448,641 2.81 58,581 58,711 2.06 % $ 3,486,274 $ 3,446,097 2.88 % $ 89,216 $ 89,932
Schedule of Realized Gains and Losses from Sale of Securities Classified as Available for Sale	The following is a summary of realized gains and losses from the sale of securities classified as available for sale. Gains or losses on securities sold are recorded on the trade date, using the specific identification method. Years Ended December 31 (Dollars in thousands) 2016 2015 2014 Realized gains $ 2,949 $ 1,834 $ 863 Realized losses (948 ) (259 ) (92 ) $ 2,001 $ 1,575 $ 771
Schedule of Securities in Other Assets on Company's Consolidated Balance Sheets	The Company accounts for the following securities at amortized cost, which approximates fair value, in “other assets” on the consolidated balance sheets at December 31: (Dollars in thousands) 2016 2015 Federal Home Loan Bank (FHLB) stock $ 42,326 $ 16,265 Federal Reserve Bank (FRB) stock 48,584 48,584 Other investments 2,808 1,159 $ 93,718 $ 66,008

Loans (Tables)

Loans (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Schedule of Non-Covered and Covered Loans	Loans consist of the following, segregated into legacy and acquired loans, for the periods indicated: December 31, 2016 (Dollars in thousands) Legacy Loans Acquired Loans Total Commercial loans: Real estate $ 5,623,314 $ 1,178,952 $ 6,802,266 Commercial and industrial 3,194,796 348,326 3,543,122 Energy-related 559,289 1,904 561,193 9,377,399 1,529,182 10,906,581 Residential mortgage loans: 854,216 413,184 1,267,400 Consumer and other loans: Home equity 1,783,421 372,505 2,155,926 Indirect automobile 131,048 4 131,052 Other 548,840 55,172 604,012 2,463,309 427,681 2,890,990 Total $ 12,694,924 $ 2,370,047 $ 15,064,971 December 31, 2015 (Dollars in thousands) Legacy Loans Acquired Loans Total Commercial loans: Real estate $ 4,504,062 $ 1,569,449 $ 6,073,511 Commercial and industrial 2,952,102 492,476 3,444,578 Energy-related 677,177 3,589 680,766 8,133,341 2,065,514 10,198,855 Residential mortgage loans: 694,023 501,296 1,195,319 Consumer and other loans: Home equity 1,575,643 490,524 2,066,167 Indirect automobile 246,214 84 246,298 Other 541,299 79,490 620,789 2,363,156 570,098 2,933,254 Total $ 11,190,520 $ 3,136,908 $ 14,327,428
Schedule of Aging of Loans	90 days Total Past Due Non-accrual Loans Total Loans Commercial real estate - Construction $ 740,761 $ — $ — $ — $ — $ — $ 740,761 Commercial real estate - Other 4,863,902 1,861 351 — 2,212 16,439 4,882,553 Commercial and industrial 3,158,700 3,999 870 — 4,869 31,227 3,194,796 Energy-related 407,434 — 1,526 — 1,526 150,329 559,289 Residential mortgage 836,509 2,012 1,577 1,104 4,693 13,014 854,216 Consumer - Home equity 1,768,763 5,249 1,430 — 6,679 7,979 1,783,421 Consumer - Indirect automobile 127,054 2,551 405 — 2,956 1,038 131,048 Consumer - Credit card 81,602 199 99 — 298 624 82,524 Consumer - Other 462,650 2,155 618 — 2,773 893 466,316 Total $ 12,447,375 $ 18,026 $ 6,876 $ 1,104 $ 26,006 $ 221,543 $ 12,694,924 December 31, 2015 Legacy loans Accruing (Dollars in thousands) Current or less than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Total Loans Commercial real estate - Construction $ 635,560 $ 801 $ — $ — $ 801 $ 120 $ 636,481 Commercial real estate - Other 3,848,584 2,687 793 95 3,575 15,422 3,867,581 Commercial and industrial 2,943,409 1,208 739 87 2,034 6,659 2,952,102 Energy-related 670,081 15 — — 15 7,081 677,177 Residential mortgage 676,347 1,075 2,485 442 4,002 13,674 694,023 Consumer - Home equity 1,565,596 3,549 870 — 4,419 5,628 1,575,643 Consumer - Indirect automobile 242,328 2,187 518 — 2,705 1,181 246,214 Consumer - Credit card 76,360 394 113 — 507 394 77,261 Consumer - Other 460,594 1,923 752 — 2,675 769 464,038 Total $ 11,118,859 $ 13,839 $ 6,270 $ 624 $ 20,733 $ 50,928 $ 11,190,520 December 31, 2016 Acquired loans (1) (2) Accruing (Dollars in thousands) Current or Less Than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Discount/Premium Acquired Impaired Loans Total Loans Commercial real estate - Construction $ 26,714 $ — $ — $ — $ — $ 1,946 $ (243 ) $ 32,991 $ 61,408 Commercial real estate - Other 871,492 716 55 32 803 1,221 (3,649 ) 247,677 1,117,544 Commercial and industrial 314,990 73 51 — 124 1,317 (837 ) 32,732 348,326 Energy-related 1,910 — — — — — (6 ) — 1,904 Residential mortgage 290,031 328 989 — 1,317 719 (1,835 ) 122,952 413,184 Consumer - Home equity 286,411 1,078 189 250 1,517 1,395 (5,237 ) 88,419 372,505 Consumer - Indirect automobile — — — — — — — 4 4 Consumer - Credit Card 468 — — — — — — — 468 Consumer - Other 49,449 391 97 — 488 360 (1,004 ) 5,411 54,704 Total $ 1,841,465 $ 2,586 $ 1,381 $ 282 $ 4,249 $ 6,958 $ (12,811 ) $ 530,186 $ 2,370,047 December 31, 2015 Acquired loans (1) (2) Accruing (Dollars in thousands) Current or Less Than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Discount/Premium Acquired Impaired Loans Total Loans Commercial real estate - Construction $ 69,167 $ 180 $ 117 $ — $ 297 $ — $ (358 ) $ 56,320 $ 125,426 Commercial real estate - Other 1,090,688 861 705 — 1,566 1,491 (4,479 ) 354,757 1,444,023 Commercial and industrial 442,454 623 — — 623 1,154 (2,517 ) 50,762 492,476 Energy-related 2,186 — — — — 170 2 1,231 3,589 Residential mortgage 365,261 7 940 — 947 1,109 (6,601 ) 140,580 501,296 Consumer - Home equity 381,107 622 416 291 1,329 1,291 (7,333 ) 114,130 490,524 Consumer - Indirect automobile 19 — — — — — — 65 84 Consumer - Credit Card — — — — — — — 582 582 Consumer - Other 74,385 468 127 — 595 206 (2,570 ) 6,292 78,908 Total $ 2,425,267 $ 2,761 $ 2,305 $ 291 $ 5,357 $ 5,421 $ (23,856 ) $ 724,719 $ 3,136,908 (1) Past due and non-accrual information presents acquired loans at the gross loan balance, prior to application of discounts. (2) Past due and non-accrual loan amounts exclude acquired impaired loans, even if contractually past due or if the Company does not expect to receive payment in full, as the Company is currently accreting interest income over the expected life of the loans." id="sjs-B5">The following tables provide an analysis of the aging of loans as of December 31, 2016 and 2015. Due to the difference in accounting for acquired loans, the tables below further segregate the Company’s loans between loans originated, or renewed and underwritten by the Company ("legacy loans") and acquired loans. December 31, 2016 Legacy loans Accruing (Dollars in thousands) Current or less than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Total Loans Commercial real estate - Construction $ 740,761 $ — $ — $ — $ — $ — $ 740,761 Commercial real estate - Other 4,863,902 1,861 351 — 2,212 16,439 4,882,553 Commercial and industrial 3,158,700 3,999 870 — 4,869 31,227 3,194,796 Energy-related 407,434 — 1,526 — 1,526 150,329 559,289 Residential mortgage 836,509 2,012 1,577 1,104 4,693 13,014 854,216 Consumer - Home equity 1,768,763 5,249 1,430 — 6,679 7,979 1,783,421 Consumer - Indirect automobile 127,054 2,551 405 — 2,956 1,038 131,048 Consumer - Credit card 81,602 199 99 — 298 624 82,524 Consumer - Other 462,650 2,155 618 — 2,773 893 466,316 Total $ 12,447,375 $ 18,026 $ 6,876 $ 1,104 $ 26,006 $ 221,543 $ 12,694,924 December 31, 2015 Legacy loans Accruing (Dollars in thousands) Current or less than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Total Loans Commercial real estate - Construction $ 635,560 $ 801 $ — $ — $ 801 $ 120 $ 636,481 Commercial real estate - Other 3,848,584 2,687 793 95 3,575 15,422 3,867,581 Commercial and industrial 2,943,409 1,208 739 87 2,034 6,659 2,952,102 Energy-related 670,081 15 — — 15 7,081 677,177 Residential mortgage 676,347 1,075 2,485 442 4,002 13,674 694,023 Consumer - Home equity 1,565,596 3,549 870 — 4,419 5,628 1,575,643 Consumer - Indirect automobile 242,328 2,187 518 — 2,705 1,181 246,214 Consumer - Credit card 76,360 394 113 — 507 394 77,261 Consumer - Other 460,594 1,923 752 — 2,675 769 464,038 Total $ 11,118,859 $ 13,839 $ 6,270 $ 624 $ 20,733 $ 50,928 $ 11,190,520 December 31, 2016 Acquired loans (1) (2) Accruing (Dollars in thousands) Current or Less Than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Discount/Premium Acquired Impaired Loans Total Loans Commercial real estate - Construction $ 26,714 $ — $ — $ — $ — $ 1,946 $ (243 ) $ 32,991 $ 61,408 Commercial real estate - Other 871,492 716 55 32 803 1,221 (3,649 ) 247,677 1,117,544 Commercial and industrial 314,990 73 51 — 124 1,317 (837 ) 32,732 348,326 Energy-related 1,910 — — — — — (6 ) — 1,904 Residential mortgage 290,031 328 989 — 1,317 719 (1,835 ) 122,952 413,184 Consumer - Home equity 286,411 1,078 189 250 1,517 1,395 (5,237 ) 88,419 372,505 Consumer - Indirect automobile — — — — — — — 4 4 Consumer - Credit Card 468 — — — — — — — 468 Consumer - Other 49,449 391 97 — 488 360 (1,004 ) 5,411 54,704 Total $ 1,841,465 $ 2,586 $ 1,381 $ 282 $ 4,249 $ 6,958 $ (12,811 ) $ 530,186 $ 2,370,047 December 31, 2015 Acquired loans (1) (2) Accruing (Dollars in thousands) Current or Less Than 30 days past due 30-59 days 60-89 days > 90 days Total Past Due Non-accrual Loans Discount/Premium Acquired Impaired Loans Total Loans Commercial real estate - Construction $ 69,167 $ 180 $ 117 $ — $ 297 $ — $ (358 ) $ 56,320 $ 125,426 Commercial real estate - Other 1,090,688 861 705 — 1,566 1,491 (4,479 ) 354,757 1,444,023 Commercial and industrial 442,454 623 — — 623 1,154 (2,517 ) 50,762 492,476 Energy-related 2,186 — — — — 170 2 1,231 3,589 Residential mortgage 365,261 7 940 — 947 1,109 (6,601 ) 140,580 501,296 Consumer - Home equity 381,107 622 416 291 1,329 1,291 (7,333 ) 114,130 490,524 Consumer - Indirect automobile 19 — — — — — — 65 84 Consumer - Credit Card — — — — — — — 582 582 Consumer - Other 74,385 468 127 — 595 206 (2,570 ) 6,292 78,908 Total $ 2,425,267 $ 2,761 $ 2,305 $ 291 $ 5,357 $ 5,421 $ (23,856 ) $ 724,719 $ 3,136,908 (1) Past due and non-accrual information presents acquired loans at the gross loan balance, prior to application of discounts. (2) Past due and non-accrual loan amounts exclude acquired impaired loans, even if contractually past due or if the Company does not expect to receive payment in full, as the Company is currently accreting interest income over the expected life of the loans.
Schedule of Carrying Amount of Loans Acquired	The tables below show the balances acquired during 2015 for these two subsections of the acquired portfolio as of the acquisition date. (Dollars in thousands) Acquired Non-Impaired Loans Contractually required principal and interest at acquisition $ 2,384,114 Expected losses and foregone interest (15,539 ) Cash flows expected to be collected at acquisition 2,368,575 Fair value of acquired loans at acquisition $ 2,105,466 (Dollars in thousands) Acquired Impaired Loans Contractually required principal and interest at acquisition $ 76,445 Non-accretable difference (expected losses and foregone interest) (11,867 ) Cash flows expected to be collected at acquisition 64,578 Accretable yield (6,823 ) Basis in acquired loans at acquisition $ 57,755
Summary of Changes in Accretable Yields of Acquired Loans	The following is a summary of changes in the accretable difference for all loans accounted for under ASC 310-30 during the years ended December 31: (Dollars in thousands) 2016 2015 2014 Balance at beginning of period $ 227,502 $ 287,651 $ 354,892 Additions — 6,823 13,848 Transfers from non-accretable difference to accretable yield 5,490 9,916 25,844 Accretion (68,211 ) (80,479 ) (103,233 ) Changes in expected cash flows not affecting non-accretable differences (1) 10,273 3,591 (3,700 ) Balance at end of period $ 175,054 $ 227,502 $ 287,651 (1) Includes changes in cash flows expected to be collected due to the impact of changes in actual or expected timing of liquidation events, modifications, changes in interest rates and changes in prepayment assumptions.
Schedule of Modified TDRs	The following table provides information on how the TDRs were modified during the years ended December 31: (Dollars in thousands) 2016 2015 Extended maturities $ 75,315 $ 15,594 Interest rate adjustment 193 — Maturity and interest rate adjustment 2,470 23,374 Movement to or extension of interest-rate only payments 27,931 241 Forbearance 76,819 122 Other concession(s) (1) 39,708 17,710 Total $ 222,436 $ 57,041 (1) Other concessions may include covenant waivers, forgiveness of principal or interest associated with a customer bankruptcy, or a combination of any of the above concessions.
Schedule of Subsequently Defaulted TDRs	The following table presents the end of period balance for loans modified in a TDR during the years ended December 31: 2016 2015 (In thousands, except number of loans) Number of Loans Pre-modification Outstanding Recorded Investment Post-modification Outstanding Recorded Investment Number of Loans Pre-modification Outstanding Recorded Investment Post-modification Outstanding Recorded Investment Commercial real estate 44 $ 30,844 $ 24,997 11 $ 26,764 $ 25,250 Commercial and industrial 59 36,379 34,415 26 21,233 18,114 Energy-related 24 133,933 141,848 2 9,797 9,484 Residential mortgage 43 5,141 4,946 1 70 68 Consumer - Home equity 158 13,273 12,568 50 4,440 3,865 Consumer - Indirect 79 983 792 6 79 79 Consumer - Other 116 3,087 2,870 17 248 181 Total 523 $ 223,640 $ 222,436 113 $ 62,631 $ 57,041 Information detailing TDRs that defaulted during the years ended December 31, 2016 and 2015 and were modified in the previous twelve months (i.e., the twelve months prior to the default) is presented in the following table. The Company has defined a default as any loan with a loan payment that is currently past due greater than 30 days , or was past due greater than 30 days at any point during the previous twelve months, or since the date of modification, whichever is shorter. December 31, 2016 December 31, 2015 (In thousands, except number of loans) Number of Loans Recorded Investment Number of Loans Recorded Investment Commercial real estate 9 $ 467 6 $ 22,075 Commercial and industrial 21 12,996 20 8,970 Energy-related 2 5,034 1 3,120 Residential mortgage 8 405 — — Consumer - Home Equity 25 1,379 20 1,547 Consumer - Indirect automobile 37 338 6 79 Consumer - Other 22 606 9 2 Total 124 $ 21,225 62 $ 35,793

Allowance for Credit Losses a37

Allowance for Credit Losses and Credit Quality (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Schedule of Allowance for Loan Losses for Covered and Non-Covered Loan Portfolios	A summary of changes in the allowance for credit losses for the years ended December 31 is as follows: 2016 (Dollars in thousands) Legacy Loans Acquired Loans Total Allowance for credit losses Allowance for loan losses at beginning of period $ 93,808 $ 44,570 $ 138,378 Provision for (Reversal of) loan losses before benefit attributable to FDIC loss share agreements 44,791 (1,864 ) 42,927 Adjustment attributable to FDIC loss share arrangements — 1,497 1,497 Net provision for loan losses 44,791 (367 ) 44,424 Adjustment attributable to FDIC loss share arrangements — (1,497 ) (1,497 ) Transfer of balance to OREO and other (9 ) (2,772 ) (2,781 ) Loans charged-off (38,055 ) (1,784 ) (39,839 ) Recoveries 5,034 1,000 6,034 Allowance for loan losses at end of period $ 105,569 $ 39,150 $ 144,719 Reserve for unfunded commitments at beginning of period $ 14,145 $ — $ 14,145 Provision for (Reversal of) unfunded lending commitments (2,904 ) — (2,904 ) Reserve for unfunded commitments at end of period $ 11,241 $ — $ 11,241 Allowance for credit losses at end of period $ 116,810 $ 39,150 $ 155,960 2015 Legacy Loans Acquired Loans Total Allowance for credit losses Allowance for loan losses at beginning of period $ 76,174 $ 53,957 $ 130,131 Provision for loan losses before benefit attributable to FDIC loss share agreements 27,711 1,837 29,548 Adjustment attributable to FDIC loss share arrangements — 1,360 1,360 Net provision for loan losses 27,711 3,197 30,908 Adjustment attributable to FDIC loss share arrangements — (1,360 ) (1,360 ) Transfer of balance to OREO and other — (10,419 ) (10,419 ) Loans charged-off (15,778 ) (1,523 ) (17,301 ) Recoveries 5,701 718 6,419 Allowance for loan losses at end of period $ 93,808 $ 44,570 $ 138,378 Reserve for unfunded commitments at beginning of period $ 11,801 $ — $ 11,801 Provision for unfunded lending commitments 2,344 — 2,344 Reserve for unfunded commitments at end of period $ 14,145 $ — $ 14,145 Allowance for credit losses at end of period $ 107,953 $ 44,570 $ 152,523 2014 Legacy Loans Acquired Loans Total Allowance for credit losses Allowance for loan losses at beginning of period $ 67,342 $ 75,732 $ 143,074 Provision for loan losses before benefit attributable to FDIC loss share agreements 14,274 526 14,800 Adjustment attributable to FDIC loss share arrangements — 4,260 4,260 Net provision for loan losses $ 14,274 $ 4,786 $ 19,060 Adjustment attributable to FDIC loss share arrangements $ — $ (4,260 ) $ (4,260 ) Transfer of balance to OREO and other — (22,157 ) (22,157 ) Loans charged-off (11,312 ) (671 ) (11,983 ) Recoveries 5,870 527 6,397 Allowance for loan losses at end of period $ 76,174 $ 53,957 $ 130,131 Reserve for unfunded commitments at beginning of period $ 11,147 $ — $ 11,147 Provision for unfunded lending commitments 654 — 654 Reserve for unfunded commitments at end of period $ 11,801 $ — $ 11,801 Allowance for credit losses at end of period $ 87,975 $ 53,957 $ 141,932 A summary of changes in the allowance for credit losses for legacy loans, by loan portfolio type, for the years ended December 31 is as follows: 2016 (Dollars in thousands) Commercial Real Estate Commercial and Industrial Energy-related Residential Mortgage Consumer Total Allowance for loan losses at beginning of period $ 24,658 $ 23,283 $ 23,863 $ 3,947 $ 18,057 $ 93,808 Provision for (Reversal of) loan losses 4,042 15,476 14,776 64 10,433 44,791 Transfer of balance to OREO and other — — — (9 ) — (9 ) Loans charged off (4,316 ) (3,720 ) (16,993 ) (313 ) (12,713 ) (38,055 ) Recoveries 1,024 395 840 146 2,629 5,034 Allowance for loan losses at end of period $ 25,408 $ 35,434 $ 22,486 $ 3,835 $ 18,406 $ 105,569 Reserve for unfunded commitments at beginning of period $ 4,160 $ 3,448 $ 2,665 $ 830 $ 3,042 $ 14,145 Provision for (Reversal of) unfunded commitments (954 ) 87 (1,662 ) (173 ) (202 ) (2,904 ) Reserve for unfunded commitments at end of period $ 3,206 $ 3,535 $ 1,003 $ 657 $ 2,840 $ 11,241 Allowance on loans individually evaluated for impairment $ 641 $ 10,864 $ 9,769 $ 144 $ 1,358 $ 22,776 Allowance on loans collectively evaluated for impairment 24,767 24,570 12,717 3,691 17,048 82,793 Loans, net of unearned income: Balance at end of period $ 5,623,314 $ 3,194,796 $ 559,289 $ 854,216 $ 2,463,309 $ 12,694,924 Balance at end of period individually evaluated for impairment 34,031 41,518 196,327 4,312 16,457 292,645 Balance at end of period collectively evaluated for impairment 5,589,283 3,153,278 $ 362,962 849,904 2,446,852 12,402,279 2015 (Dollars in thousands) Commercial Real Estate Commercial and Industrial Energy-related Residential Mortgage Consumer Total Allowance for loan losses at beginning of period $ 26,752 $ 24,455 $ 5,949 $ 2,678 $ 16,340 $ 76,174 Provision for (Reversal of) loan losses (1,466 ) (103 ) 17,917 1,493 9,870 27,711 Loans charged off (2,525 ) (1,276 ) (3 ) (291 ) (11,683 ) (15,778 ) Recoveries 1,897 207 — 67 3,530 5,701 Allowance for loan losses at end of period $ 24,658 $ 23,283 $ 23,863 $ 3,947 $ 18,057 $ 93,808 Reserve for unfunded commitments at beginning of period $ 3,370 $ 3,733 $ 1,596 $ 168 $ 2,934 $ 11,801 Provision for (Reversal of) unfunded commitments 790 (285 ) 1,069 662 108 2,344 Reserve for unfunded commitments at end of period $ 4,160 $ 3,448 $ 2,665 $ 830 $ 3,042 $ 14,145 Allowance on loans individually evaluated for impairment $ 1,246 $ 272 $ 2,122 $ 1 $ 352 $ 3,993 Allowance on loans collectively evaluated for impairment 23,412 23,011 21,741 3,946 17,705 89,815 Loans, net of unearned income: Balance at end of period $ 4,504,062 $ 2,952,102 $ 677,177 $ 694,023 $ 2,363,156 $ 11,190,520 Balance at end of period individually evaluated for impairment 28,857 20,086 13,020 70 4,608 66,641 Balance at end of period collectively evaluated for impairment 4,475,205 2,932,016 $ 664,157 693,953 2,358,548 11,123,879 2014 (Dollars in thousands) Commercial Real Estate Commercial and Industrial Energy-related Residential Mortgage Consumer Total Allowance for loan losses at beginning of period $ 22,872 $ 20,839 $ 6,878 $ 2,546 $ 14,207 $ 67,342 Provision for (Reversal of) loan losses 2,171 4,971 (929 ) 566 7,495 14,274 Loans charged off (1,164 ) (1,400 ) — (578 ) (8,170 ) (11,312 ) Recoveries 2,873 45 — 144 2,808 5,870 Allowance for loan losses at end of period $ 26,752 $ 24,455 $ 5,949 $ 2,678 $ 16,340 $ 76,174 Reserve for unfunded commitments at beginning of period $ 3,071 $ 1,814 $ 3,043 $ 72 $ 3,147 $ 11,147 Provision for (Reversal of) unfunded commitments 299 1,919 (1,447 ) 96 (213 ) 654 Reserve for unfunded commitments at end of period $ 3,370 $ 3,733 $ 1,596 $ 168 $ 2,934 $ 11,801 Allowance on loans individually evaluated for impairment $ 20 $ 407 $ — $ — $ 3 $ 430 Allowance on loans collectively evaluated for impairment 26,732 24,048 5,949 2,678 16,337 75,744 Loans, net of unearned income: Balance at end of period $ 3,676,811 $ 2,452,521 $ 872,866 $ 527,694 $ 2,138,822 $ 9,668,714 Balance at end of period individually evaluated for impairment 7,036 3,965 — — 699 11,700 Balance at end of period collectively evaluated for impairment 3,669,775 2,448,556 872,866 527,694 2,138,123 9,657,014 A summary of changes in the allowance for loan losses for acquired loans, by loan portfolio type, for the years ended December 31 is as follows: 2016 (Dollars in thousands) Commercial Commercial Energy-related Residential Consumer Total Allowance for loan losses at beginning of period $ 25,979 $ 2,819 $ 125 $ 7,841 $ 7,806 $ 44,570 Provision for (Reversal of) loan losses (1,598 ) 1,645 (86 ) 759 (1,087 ) (367 ) Decrease in FDIC loss share receivable (34 ) (50 ) — (1,090 ) (323 ) (1,497 ) Transfer of balance to OREO and other (868 ) (519 ) — (132 ) (1,253 ) (2,772 ) Loans charged off (22 ) (932 ) — — (830 ) (1,784 ) Recoveries 117 267 — 34 582 1,000 Allowance for loan losses at end of period $ 23,574 $ 3,230 $ 39 $ 7,412 $ 4,895 $ 39,150 Allowance on loans individually evaluated for impairment $ 737 $ 780 $ — $ — $ — $ 1,517 Allowance on loans collectively evaluated for impairment 22,837 2,450 39 7,412 4,895 37,633 Loans, net of unearned income: Balance at end of period $ 1,178,952 $ 348,326 $ 1,904 $ 413,184 $ 427,681 $ 2,370,047 Balance at end of period individually evaluated for impairment 8,246 1,879 — — 10 10,135 Balance at end of period collectively evaluated for impairment 890,038 313,715 1,904 290,232 333,837 1,829,726 Balance at end of period acquired with deteriorated credit quality 280,668 32,732 — 122,952 93,834 530,186 2015 (Dollars in thousands) Commercial Commercial Energy-related Residential Consumer Total Allowance for loan losses at beginning of period $ 29,949 $ 3,265 $ 51 $ 6,484 $ 14,208 $ 53,957 Provision for (Reversal of) loan losses 2,182 (122 ) 74 2,126 (1,063 ) 3,197 Increase (Decrease) in FDIC loss share receivable 757 (49 ) — (235 ) (1,833 ) (1,360 ) Transfer of balance to OREO and other (6,849 ) (275 ) — (491 ) (2,804 ) (10,419 ) Loans charged off (281 ) — — (71 ) (1,171 ) (1,523 ) Recoveries 221 — — 28 469 718 Allowance for loan losses at end of period $ 25,979 $ 2,819 $ 125 $ 7,841 $ 7,806 $ 44,570 Allowance on loans individually evaluated for impairment $ — $ 41 $ — $ — $ 45 $ 86 Allowance on loans collectively evaluated for impairment 25,979 2,778 125 7,841 7,761 44,484 Loans, net of unearned income: Balance at end of period $ 1,569,449 $ 492,476 $ 3,589 $ 501,296 $ 570,098 $ 3,136,908 Balance at end of period individually evaluated for impairment 720 164 — — 458 1,342 Balance at end of period collectively evaluated for impairment 1,157,652 441,550 2,358 360,716 448,571 2,410,847 Balance at end of period acquired with deteriorated credit quality 411,077 50,762 1,231 140,580 121,069 724,719 2014 (Dollars in thousands) Commercial Commercial Energy-related Residential Consumer Total Allowance for loan losses at beginning of period $ 42,026 $ 6,641 $ — $ 10,889 $ 16,176 $ 75,732 Provision for loan losses 665 536 51 1,296 2,238 4,786 Increase (Decrease) in FDIC loss share receivable 227 509 — (3,854 ) (1,142 ) (4,260 ) Transfer of balance to OREO and other (13,117 ) (4,421 ) — (1,914 ) (2,705 ) (22,157 ) Loans charged off — — — (35 ) (636 ) (671 ) Recoveries 148 — — 102 277 527 Allowance for loan losses at end of period $ 29,949 $ 3,265 $ 51 $ 6,484 $ 14,208 $ 53,957 Allowance on loans individually evaluated for impairment $ — $ — $ — $ — $ — $ — Allowance on loans collectively evaluated for impairment 29,949 3,265 51 6,484 14,208 53,957 Loans, net of unearned income: Balance at end of period $ 684,968 $ 119,174 $ 7,742 $ 552,603 $ 407,843 $ 1,772,330 Balance at end of period individually evaluated for impairment — — — — — — Balance at end of period collectively evaluated for impairment 169,338 60,584 7,742 402,347 265,168 905,179 Balance at end of period acquired with deteriorated credit quality 515,630 58,590 — 150,256 142,675 867,151
Investment in Legacy and Acquired Loans by Credit Quality Indicator	The Company’s investment in loans by credit quality indicator is presented in the following tables. The tables below further segregate the Company’s loans between loans that were originated by the Company (legacy loans) and acquired loans. Loan premiums/discounts in the tables below represent the adjustment of acquired loans to fair value at the acquisition date, as adjusted for income accretion and changes in cash flow estimates in subsequent periods. Asset risk classifications for commercial loans reflect the classification as of December 31, 2016 and 2015, respectively. Credit quality information in the tables below includes total loans acquired (including acquired impaired loans) at the gross loan balance, prior to the application of premiums/discounts, at December 31, 2016 and 2015. Loan delinquency is the primary credit quality indicator that the Company utilizes to monitor consumer asset quality. Legacy loans December 31, 2016 December 31, 2015 (Dollars in thousands) Pass Special Mention Sub- Doubtful Total Pass Special Mention Sub- Doubtful Total Commercial real estate - Construction $ 734,687 $ 2,203 $ 3,871 $ — $ 740,761 $ 634,889 $ 160 $ 1,432 $ — $ 636,481 Commercial real estate - Other 4,801,494 26,159 54,900 — 4,882,553 3,806,528 21,877 37,001 2,175 3,867,581 Commercial and industrial 3,112,300 29,763 35,199 17,534 3,194,796 2,911,396 14,826 19,888 5,992 2,952,102 Energy-related 242,123 80,084 225,724 11,358 559,289 531,657 67,937 74,272 3,311 677,177 Total $ 8,890,604 $ 138,209 $ 319,694 $ 28,892 $ 9,377,399 $ 7,884,470 $ 104,800 $ 132,593 $ 11,478 $ 8,133,341 Legacy loans December 31, 2016 December 31, 2015 (Dollars in thousands) Current 30+ Days Past Due Total Current 30+ Days Past Due Total Residential mortgage $ 836,509 $ 17,707 $ 854,216 $ 676,347 $ 17,676 $ 694,023 Consumer - Home equity 1,768,763 14,658 1,783,421 1,565,596 10,047 1,575,643 Consumer - Indirect automobile 127,054 3,994 131,048 242,328 3,886 246,214 Consumer - Credit card 81,602 922 82,524 76,360 901 77,261 Consumer - Other 462,650 3,666 466,316 460,594 3,444 464,038 Total $ 3,276,578 $ 40,947 $ 3,317,525 $ 3,021,225 $ 35,954 $ 3,057,179 Acquired loans December 31, 2016 December 31, 2015 (Dollars in thousands) Pass Special Sub-standard Doubtful Loss Premium/(Discount) Total Pass Special Sub-standard Doubtful Loss Premium/(Discount) Total Commercial real estate - Construction $ 46,498 $ 459 $ 3,118 $ 2,574 $ — $ 8,759 $ 61,408 $ 104,064 $ 1,681 $ 8,803 $ 771 $ — $ 10,107 $ 125,426 Commercial real 1,090,063 19,284 49,136 1,457 23 (42,419 ) 1,117,544 1,395,884 26,080 79,119 6,124 111 (63,295 ) 1,444,023 Commercial and industrial 323,154 1,416 27,749 494 — (4,487 ) 348,326 473,241 8,376 16,510 1,206 43 (6,900 ) 492,476 Energy-related 1,910 — — — — (6 ) 1,904 2,166 55 170 1,198 — — 3,589 Total $ 1,461,625 $ 21,159 $ 80,003 $ 4,525 $ 23 $ (38,153 ) $ 1,529,182 $ 1,975,355 $ 36,192 $ 104,602 $ 9,299 $ 154 $ (60,088 ) $ 2,065,514 Acquired loans December 31, 2016 December 31, 2015 (Dollars in thousands) Current 30+ Days Past Due Premium (Discount) Total Current 30+ Days Past Due Premium (Discount) Total Residential mortgage $ 424,300 $ 20,914 $ (32,030 ) $ 413,184 $ 506,103 $ 24,752 $ (29,559 ) $ 501,296 Consumer - Home equity 377,021 12,807 (17,323 ) 372,505 503,635 16,381 (29,492 ) 490,524 Consumer - Indirect automobile 12 — (8 ) 4 72 12 — 84 Consumer - Other 58,141 1,423 (4,392 ) 55,172 79,732 1,475 (1,717 ) 79,490 Total $ 859,474 $ 35,144 $ (53,753 ) $ 840,865 $ 1,089,542 $ 42,620 $ (60,768 ) $ 1,071,394
Schedule of Investment in Legacy Impaired Loans	Information on the Company’s investment in legacy impaired loans, which include all TDRs and all other non-accrual loans evaluated or measured individually for impairment purposes of determining the allowance for loan losses, is presented in the following tables as of and for the periods indicated. December 31, 2016 (Dollars in thousands) Unpaid Principal Balance Recorded Investment Related Average Interest With no related allowance recorded: Commercial real estate $ 17,299 $ 16,507 $ — $ 21,133 $ 948 Commercial and industrial 14,202 13,189 — 15,492 805 Energy-related 152,424 143,239 — 114,623 2,903 Consumer - Home equity — — — — — Consumer - Other — — — — — With an allowance recorded: Commercial real estate 17,688 17,524 (641 ) 16,771 494 Commercial and industrial 28,829 28,329 (10,864 ) 29,333 1,107 Energy-related 53,967 53,088 (9,769 ) 47,469 1,677 Residential mortgage 4,627 4,312 (144 ) 4,377 161 Consumer - Home equity 13,906 13,257 (993 ) 10,227 434 Consumer - Indirect automobile 1,037 758 (114 ) 956 49 Consumer - Other 2,447 2,442 (251 ) 1,469 102 Total $ 306,426 $ 292,645 $ (22,776 ) $ 261,850 $ 8,680 Total commercial loans $ 284,409 $ 271,876 $ (21,274 ) $ 244,821 $ 7,934 Total mortgage loans 4,627 4,312 (144 ) 4,377 161 Total consumer loans 17,390 16,457 (1,358 ) 12,652 585 December 31, 2015 (Dollars in thousands) Unpaid Principal Balance Recorded Investment Related Average Interest With no related allowance recorded: Commercial real estate $ 17,002 $ 16,145 $ — $ 15,864 $ 315 Commercial and industrial 14,571 14,340 — 18,839 1,148 Energy-related — — — — — Consumer - Home equity 730 730 — 533 22 Consumer - Other 66 66 — 66 5 With an allowance recorded: Commercial real estate 12,765 12,712 (1,246 ) 12,985 530 Commercial and industrial 5,748 5,746 (272 ) 5,975 313 Energy-related 13,046 13,020 (2,122 ) 13,899 454 Residential mortgage 70 70 (1 ) 70 5 Consumer - Home equity 3,859 3,683 (337 ) 2,453 73 Consumer - Other 130 129 (15 ) 30 3 Total $ 67,987 $ 66,641 $ (3,993 ) $ 70,714 $ 2,868 Total commercial loans $ 63,132 $ 61,963 $ (3,640 ) $ 67,562 $ 2,760 Total mortgage loans 70 70 (1 ) 70 5 Total consumer loans 4,785 4,608 (352 ) 3,082 103 December 31, 2014 (Dollars in thousands) Unpaid Principal Balance Recorded Investment Related Average Interest With no related allowance recorded: Commercial real estate $ 7,615 $ 6,680 $ — $ 6,703 $ 132 Commercial and industrial 3,710 2,483 — 2,602 39 Consumer - Home equity 748 682 — 696 19 With an allowance recorded: Commercial real estate 356 356 (20 ) 378 23 Commercial and industrial 1,590 1,482 (407 ) 1,849 24 Consumer - Other 17 17 (3 ) 18 2 Total $ 14,036 $ 11,700 $ (430 ) $ 12,246 $ 239 Total commercial loans $ 13,271 $ 11,001 $ (427 ) $ 11,532 $ 218 Total mortgage loans — — — — — Total consumer loans 765 699 (3 ) 714 21

Loss Sharing Agreements and F38

Loss Sharing Agreements and FDIC Loss Share Receivable (Tables)	12 Months Ended
	Dec. 31, 2016
Loss Sharing Agreements and FDIC Loss Share Receivable [Abstract]
Schedule of FDIC Loss Share Receivables	The following is a summary of the year-to-date activity for the FDIC loss share receivables: December 31 (Dollars in thousands) 2016 2015 Balance at beginning of period $ 39,878 $ 69,627 Reversal of loan loss provision recorded on FDIC covered loans (1,497 ) (1,360 ) Amortization (16,024 ) (23,500 ) Submission of reimbursable losses to the FDIC (1,945 ) (2,444 ) Impairment (20,402 ) — Changes due to a change in cash flow assumptions on OREO and other changes (10 ) (2,445 ) Balance at end of period $ — $ 39,878

Transfers and Servicing of Fi39

Transfers and Servicing of Financial Assets (Including Mortgage Banking Activity) (Tables)	12 Months Ended
	Dec. 31, 2016
Transfers and Servicing [Abstract]
Changes in Carrying Amount of Mortgage Loans Held-for-sale	Changes to the carrying amount of mortgage loans held for sale at December 31 are presented in the following table. (Dollars in thousands) 2016 2015 2014 Balance at beginning of period $ 166,247 $ 140,072 $ 128,442 Originations and purchases 2,460,033 2,464,588 1,675,538 Sales, net of gains (2,451,459 ) (2,432,979 ) (1,657,409 ) Mortgage loans transferred to held for investment (14,017 ) — — Other (3,763 ) (5,434 ) (6,499 ) Balance at end of period $ 157,041 $ 166,247 $ 140,072
Components of Mortgage Income	The following table details the components of mortgage income for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Fair value changes of derivatives and mortgage loans held for sale: Mortgage loans held for sale and derivatives $ 1,361 $ 2,216 $ 631 Derivative settlements, net (6,640 ) (5,017 ) (8,743 ) Gains on sales 87,925 82,671 59,156 Servicing and other income, net 1,207 792 753 $ 83,853 $ 80,662 $ 51,797
Schedule of Mortgage Servicing Rights at Carrying Value	Mortgage servicing rights had the following carrying values as of the periods indicated: December 31, 2016 December 31, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount (Dollars in thousands) Mortgage servicing rights $ 7,202 $ (3,144 ) $ 4,058 $ 6,104 $ (2,320 ) $ 3,784 In addition, there was an insignificant amount of non-mortgage servicing rights related to SBA loans as of December 31, 2016 and no non-mortgage servicing rights as of December 31, 2015.

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Schedule of Premises and Equipment	Premises and equipment consisted of the following at December 31: (Dollars in thousands) 2016 2015 Land $ 84,616 $ 84,438 Buildings 239,626 245,934 Furniture, fixtures and equipment 115,775 140,031 Total premises and equipment 440,017 470,403 Accumulated depreciation (133,644 ) (146,501 ) Total premises and equipment, net $ 306,373 $ 323,902
Schedule of Minimum Future Annual Rent Commitments	Minimum future annual rent commitments under lease agreements for the periods indicated are as follows: (Dollars in thousands) 2017 $ 15,927 2018 14,981 2019 13,980 2020 12,742 2021 10,906 2022 and thereafter 37,527 $ 106,063

Goodwill and Other Acquired I41

Goodwill and Other Acquired Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Carrying Amount of Goodwill	Changes to the carrying amount of goodwill by reporting unit for the years ended December 31, 2016 and 2015 are provided in the following table. (Dollars in thousands) IBERIABANK IMC LTC Total Balance, December 31, 2014 $ 489,183 $ 23,178 $ 5,165 $ 517,526 Goodwill acquired during the year 207,077 — — 207,077 Balance, December 31, 2015 $ 696,260 $ 23,178 $ 5,165 $ 724,603 Goodwill adjustments during the year 2,253 — — 2,253 Balance, December 31, 2016 $ 698,513 $ 23,178 $ 5,165 $ 726,856
Schedule of Definite-Lived Intangible Assets	Definite-lived intangible assets had the following carrying values included in “other assets” on the Company’s consolidated balance sheets as of December 31: 2016 2015 (Dollars in thousands) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Core deposit intangibles $ 74,001 $ (52,165 ) $ 21,836 $ 74,001 $ (43,957 ) $ 30,044 Customer relationship intangible asset 1,348 (1,064 ) 284 1,348 (984 ) 364 Non-compete agreement 63 (22 ) 41 100 (79 ) 21 Other intangible assets — — — 205 (114 ) 91 Total $ 75,412 $ (53,251 ) $ 22,161 $ 75,654 $ (45,134 ) $ 30,520
Schedule of Amortization Expense of Intangible Assets	The related amortization expense of intangible assets is as follows: (Dollars in thousands) Amount Aggregate amortization expense for the years ended December 31: 2014 $ 5,807 2015 7,811 2016 8,415 (Dollars in thousands) Estimated amortization expense for the years ended December 31: 2017 $ 6,733 2018 5,740 2019 5,019 2020 3,513 2021 1,066 2022 and thereafter 90

Derivative Instruments and Ot42

Derivative Instruments and Other Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Outstanding Derivative Instruments	Information pertaining to outstanding derivative instruments is as follows: Balance Sheet Location Asset Derivatives Fair Value Balance Sheet Location Liability Derivatives Fair Value (Dollars in thousands) December 31, 2016 December 31, 2015 December 31, 2016 December 31, 2015 Derivatives designated as hedging instruments under ASC Topic 815: Interest rate contracts Other assets $ — $ 58 Other liabilities $ 525 $ — Total derivatives designated as hedging instruments under ASC Topic 815 $ — $ 58 $ 525 $ — Derivatives not designated as hedging instruments under ASC Topic 815: Interest rate contracts Other assets $ 20,719 $ 18,077 Other liabilities $ 20,719 $ 18,077 Foreign exchange contracts Other assets 27 156 Other liabilities 26 134 Forward sales contracts Other assets 6,014 1,588 Other liabilities 794 474 Written and purchased options Other assets 12,125 10,607 Other liabilities 8,098 6,254 Other contracts Other assets 1 — Other liabilities 47 63 Total derivatives not designated as hedging instruments under ASC Topic 815 38,886 30,428 29,684 25,002 Total $ 38,886 $ 30,486 $ 30,209 $ 25,002 Asset Derivatives Notional Amount Liability Derivatives Notional Amount (Dollars in thousands) December 31, 2016 December 31, 2015 December 31, 2016 December 31, 2015 Derivatives designated as hedging instruments under ASC Topic 815: Interest rate contracts $ — $ 108,500 $ 108,500 $ — Total derivatives designated as hedging instruments under ASC Topic 815 $ — $ 108,500 $ 108,500 $ — Derivatives not designated as hedging instruments under ASC Topic 815: Interest rate contracts $ 1,033,955 $ 590,334 $ 1,033,955 $ 590,334 Foreign exchange contracts 4,474 4,392 4,474 4,392 Forward sales contracts 229,181 223,841 120,567 173,430 Written and purchased options 289,115 328,210 154,170 181,949 Other contracts 8,784 — 106,518 43,169 Total derivatives not designated as hedging instruments under ASC Topic 815 $ 1,565,509 $ 1,146,777 $ 1,419,684 $ 993,274 Total $ 1,565,509 $ 1,255,277 $ 1,528,184 $ 993,274
Offsetting Assets	The following table reconciles the gross amounts presented in the consolidated balance sheets to the net amounts that would result in the event of offset. December 31, 2016 Gross Amounts Presented in the Balance Sheet Gross Amounts Not Offset in the Balance Sheet Net (Dollars in thousands) Derivatives Collateral (1) Derivatives subject to master netting arrangements Derivative assets Interest rate contracts not designated as hedging instruments $ 20,719 $ (9,677 ) $ — $ 11,042 Written and purchased options 8,085 — — 8,085 Total derivative assets subject to master netting arrangements $ 28,804 $ (9,677 ) $ — $ 19,127 Derivative liabilities Interest rate contracts designated as hedging instruments $ 525 $ — $ (181 ) $ 344 Interest rate contracts not designated as hedging instruments 20,719 (9,677 ) (1,711 ) 9,331 Total derivative liabilities subject to master netting arrangements $ 21,244 $ (9,677 ) $ (1,892 ) $ 9,675 (1) Consists of cash collateral recorded at cost, which approximates fair value, and investment securities . December 31, 2015 Gross Amounts Presented in the Balance Sheet Gross Amounts Not Offset in the Balance Sheet Net (Dollars in thousands) Derivatives Collateral (1) Derivatives subject to master netting arrangements Derivative assets Interest rate contracts designated as hedging instruments $ 100 $ (43 ) $ — $ 57 Interest rate contracts not designated as hedging instruments 18,241 (119 ) — 18,122 Written and purchased options 6,255 — — 6,255 Total derivative assets subject to master netting arrangements $ 24,596 $ (162 ) $ — $ 24,434 Derivative liabilities Interest rate contracts designated as hedging instruments $ 43 $ (43 ) $ — $ — Interest rate contracts not designated as hedging instruments 18,241 (119 ) (10,877 ) 7,245 Total derivative liabilities subject to master netting arrangements $ 18,284 $ (162 ) $ (10,877 ) $ 7,245 (1) Consists of cash collateral recorded at cost, which approximates fair value, and investment securities.
Offsetting Liabilities	The following table reconciles the gross amounts presented in the consolidated balance sheets to the net amounts that would result in the event of offset. December 31, 2016 Gross Amounts Presented in the Balance Sheet Gross Amounts Not Offset in the Balance Sheet Net (Dollars in thousands) Derivatives Collateral (1) Derivatives subject to master netting arrangements Derivative assets Interest rate contracts not designated as hedging instruments $ 20,719 $ (9,677 ) $ — $ 11,042 Written and purchased options 8,085 — — 8,085 Total derivative assets subject to master netting arrangements $ 28,804 $ (9,677 ) $ — $ 19,127 Derivative liabilities Interest rate contracts designated as hedging instruments $ 525 $ — $ (181 ) $ 344 Interest rate contracts not designated as hedging instruments 20,719 (9,677 ) (1,711 ) 9,331 Total derivative liabilities subject to master netting arrangements $ 21,244 $ (9,677 ) $ (1,892 ) $ 9,675 (1) Consists of cash collateral recorded at cost, which approximates fair value, and investment securities . December 31, 2015 Gross Amounts Presented in the Balance Sheet Gross Amounts Not Offset in the Balance Sheet Net (Dollars in thousands) Derivatives Collateral (1) Derivatives subject to master netting arrangements Derivative assets Interest rate contracts designated as hedging instruments $ 100 $ (43 ) $ — $ 57 Interest rate contracts not designated as hedging instruments 18,241 (119 ) — 18,122 Written and purchased options 6,255 — — 6,255 Total derivative assets subject to master netting arrangements $ 24,596 $ (162 ) $ — $ 24,434 Derivative liabilities Interest rate contracts designated as hedging instruments $ 43 $ (43 ) $ — $ — Interest rate contracts not designated as hedging instruments 18,241 (119 ) (10,877 ) 7,245 Total derivative liabilities subject to master netting arrangements $ 18,284 $ (162 ) $ (10,877 ) $ 7,245 (1) Consists of cash collateral recorded at cost, which approximates fair value, and investment securities.
Effect of Derivatives on the Consolidated Financial Statements	At December 31, 2016, 2015, and 2014, and for the years then ended, information pertaining to the effect of the hedging instruments on the consolidated financial statements is as follows: Location of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) Amount of Gain (Loss) Recognized in OCI net of taxes (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income net of taxes (Effective Portion) (Dollars in thousands) For the Years Ended December 31 Derivatives in ASC Topic 815 Cash Flow Hedging Relationships 2016 2015 2014 2016 2015 2014 2016 2015 2014 Interest rate contracts $ (428 ) $ 38 $ — Interest expense $ 50 $ — $ — Interest expense $ — $ — $ (1 ) Total $ (428 ) $ 38 $ — $ 50 $ — $ — $ — $ — $ (1 ) Information pertaining to the effect of derivatives not designated as hedging instruments on the consolidated financial statements as of December 31, is as follows: Location of Gain (Loss) Recognized in Income on Derivatives Amount of Gain (Loss) Recognized in Income on Derivatives (Dollars in thousands) 2016 2015 2014 Interest rate contracts (1) Other income $ 8,830 $ 4,143 $ 2,513 Foreign exchange contracts Other income 15 22 — Forward sales contracts Mortgage income (1,731 ) (2,947 ) (3,225 ) Written and purchased options Mortgage income (327 ) 274 (5,739 ) Other contracts Other income 17 — — Total $ 6,804 $ 1,492 $ (6,451 )
Schedule of Derivative Instruments	At December 31, additional information pertaining to outstanding interest rate swap agreements not designated as hedging instruments is as follows: (Dollars in thousands) 2016 2015 2014 Weighted average pay rate 4.1 % 3.2 % 2.9 % Weighted average receive rate 2.5 % 0.9 % 0.4 % Weighted average maturity in years 7.4 years 7.5 years 7.7 years Unrealized gain (loss) relating to interest rate swaps $ — $ — $ —

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2016
Banking and Thrift [Abstract]
Schedule of Deposits by Type	Deposits at December 31 are summarized as follows: (Dollars in thousands) 2016 2015 Non-interest-bearing deposits $ 4,928,878 $ 4,352,229 Negotiable order of withdrawal (NOW) 3,314,281 2,974,176 Money market deposits accounts (MMDA) 6,219,532 6,010,882 Savings deposits 814,385 716,838 Certificates of deposit and other time deposits 2,131,207 2,124,623 $ 17,408,283 $ 16,178,748
Schedule of Time Deposits	Total time deposits summarized by denomination at December 31 are as follows: (Dollars in thousands) 2016 2015 Time deposits less than $250,000 $ 1,661,631 $ 1,456,804 Time deposits greater than $250,000 469,576 667,819 $ 2,131,207 $ 2,124,623
Schedule of Maturities of Certificates of Deposit	A schedule of maturities of all time deposits as of December 31, 2016 is as follows: (Dollars in thousands) Years ending December 31 2017 $ 1,335,041 2018 507,162 2019 96,509 2020 83,623 2021 60,468 2022 and thereafter 48,404 $ 2,131,207

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Summary of Short-Term Borrowings	Short-term borrowings at December 31 are summarized as follows: (Dollars in thousands) 2016 2015 Federal Home Loan Bank advances $ 175,000 $ 110,000 Securities sold under agreements to repurchase 334,136 216,617 $ 509,136 $ 326,617 The levels of securities sold under agreements to repurchase and FHLB advances can fluctuate significantly on a day-to-day basis, depending on funding needs and which sources are used to satisfy those needs. All such arrangements are considered typical of the banking and brokerage industries and are accounted for as borrowings. Securities sold under agreements to repurchase, which are classified as secured borrowings, generally mature daily and are reflected at the amount of cash received in connection with the transaction. The Company may be required to provide additional collateral based on the fair value of the underlying securities. Additional information on the Company’s short-term borrowings for the years indicated is as follows: (Dollars in thousands) 2016 2015 2014 Outstanding at December 31 $ 509,136 $ 326,617 $ 845,742 Maximum month-end outstanding balance 807,993 798,933 1,034,741 Average daily outstanding balance 614,073 426,011 782,033 Average rate during the year 0.39 % 0.18 % 0.17 % Average rate at year end 0.30 % 0.20 % 0.18 %

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Schedule of Long-Term Debt	Long-term debt at December 31 is summarized as follows: (Dollars in thousands) 2016 2015 IBERIABANK: Federal Home Loan Bank notes, 0.864% to 7.040% $ 480,118 $ 136,628 Notes payable - Investment fund contribution, 7 to 40 year term, 0.50% to 3.60% fixed 28,725 83,709 508,843 220,337 IBERIABANK Corporation (junior subordinated debt): Statutory Trust I, 3 month LIBOR (1) , plus 3.25%, issued November 2002 10,310 10,310 Statutory Trust II, 3 month LIBOR (1) , plus 3.15%, issued June 2003 10,310 10,310 Statutory Trust III, 3 month LIBOR (1) , plus 2.00%, issued September 2004 10,310 10,310 Statutory Trust IV, 3 month LIBOR (1) , plus 1.60%, issued October 2006 15,464 15,464 American Horizons Statutory Trust I, 3 month LIBOR (1) , plus 3.15%, assumed January 2005 6,186 6,186 Statutory Trust V, 3 month LIBOR (1) , plus 1.435%, issued June 2007 10,310 10,310 Statutory Trust VI, 3 month LIBOR (1) , plus 2.75%, issued November 2007 12,372 12,372 Statutory Trust VII, 3 month LIBOR (1) , plus 2.54%, issued November 2007 13,403 13,403 Statutory Trust VIII, 3 month LIBOR (1) , plus 3.50%, issued March 2008 7,217 7,217 OMNI Trust I, 3 month LIBOR (1) , plus 3.30%, assumed May 2011 8,248 8,248 OMNI Trust II, 3 month LIBOR (1) , plus 2.79%, assumed May 2011 7,732 7,732 GA Commerce Trust II, 3 month LIBOR (1) , plus 1.64%, assumed May 2015 8,248 8,248 120,110 120,110 $ 628,953 $ 340,447 (1) The interest rate on the Company’s long-term debt indexed to LIBOR is based on the 3-month LIBOR rate. The 3-month LIBOR rate w as 1.00% and 0.61% at December 31, 2016 and 2015, respectively.
Maturities of Long-Term Debt	Advances and long-term debt at December 31, 2016 have maturities or call dates in future years as follows: (Dollars in thousands) 2017 $ 55,516 2018 233,667 2019 97,042 2020 15,263 2021 55,564 2022 and thereafter 171,901 $ 628,953

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Schedule of Provision for Income Tax Expense	The provision for income tax expense consists of the following for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Current expense $ 103,335 $ 67,025 $ 69,612 Deferred expense (benefit) (16,654 ) 4,551 (25,027 ) Tax credits (7,112 ) (11,268 ) (12,012 ) Amortization on qualified affordable housing tax credits 4,185 2,023 1,005 Tax benefits attributable to items charged to equity and goodwill 1,439 1,763 2,105 $ 85,193 $ 64,094 $ 35,683
Reconciliation of Effective Tax Rate	The provision for federal income taxes differs from the amount computed by applying the federal income tax statutory rate of 35 percent on income before income tax expense as indicated in the following analysis for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Federal tax based on statutory rate $ 95,189 $ 72,428 $ 49,373 Increase (decrease) resulting from: Effect of tax-exempt income (8,203 ) (6,919 ) (7,064 ) Interest and other nondeductible expenses 3,250 5,899 2,642 State taxes, net of federal benefit 4,770 3,955 2,531 Tax credits (7,112 ) (11,268 ) (12,012 ) Amortization on qualified affordable housing tax credits 4,185 2,023 1,005 Other (6,886 ) (2,024 ) (792 ) $ 85,193 $ 64,094 $ 35,683 Effective tax rate 31.3 % 31.0 % 25.3 %
Deferred Tax Assets and Liabilities	The net deferred tax asset at December 31 is as follows: (Dollars in thousands) 2016 2015 Deferred tax asset: NOL carryforward $ 19,584 $ 17,258 Allowance for credit losses 58,036 56,446 Deferred compensation 10,852 7,528 Basis difference in acquired assets 32,923 48,256 Unrealized loss on securities available for sale 14,019 854 OREO 4,498 6,210 Other 14,754 10,438 154,666 146,990 Deferred tax liability: Basis difference in acquired assets (13,150 ) (31,975 ) Gain on acquisition — (212 ) FHLB stock (270 ) (122 ) Premises and equipment (6,132 ) (1,658 ) Acquisition intangibles (8,134 ) (7,648 ) Deferred loan costs (4,702 ) (4,610 ) Investments acquired — (167 ) Other (9,196 ) (16,694 ) (41,584 ) (63,086 ) Net deferred tax asset $ 113,082 $ 83,904

Shareholders' Equity, Capital47

Shareholders' Equity, Capital Ratios and Other Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2016
Banking and Thrift [Abstract]
Schedule of Preferred Stock	The following table presents a summary of the Company's non-cumulative perpetual preferred stock: 2016 2015 Issuance Date Earliest Redemption Date Annual Dividend Rate Liquidation Amount Carrying Amount Carrying Amount (Dollars in millions) Series B Preferred Stock 8/5/2015 8/1/2025 6.625 % $ 80,000 $ 76,812 $ 76,812 Series C Preferred Stock 5/9/2016 5/1/2026 6.600 % 57,500 55,285 — $ 137,500 $ 132,097 $ 76,812
Actual Capital Amounts and Ratios	The Company’s and IBERIABANK’s actual capital amounts and ratios as of December 31 are presented in the following table. (Dollars in thousands) 2016 Minimum Well-Capitalized Actual Amount Ratio Amount Ratio Amount Ratio Tier 1 Leverage Consolidated $ 818,440 4.00 % N/A N/A $ 2,221,528 10.86 % IBERIABANK 816,152 4.00 1,020,190 5.00 1,878,703 9.21 Common Equity Tier 1 (CET1) (1) Consolidated $ 794,334 4.50 % N/A N/A $ 2,089,431 11.84 % IBERIABANK 792,111 4.50 1,144,160 6.50 1,878,703 10.67 Tier 1 Risk-Based Capital (1) Consolidated $ 1,059,112 6.00 % N/A N/A $ 2,221,528 12.59 % IBERIABANK 1,056,147 6.00 1,408,197 8.00 1,878,703 10.67 Total Risk-Based Capital (1) Consolidated $ 1,412,149 8.00 % N/A N/A $ 2,493,988 14.13 % IBERIABANK 1,408,197 8.00 1,760,246 10.00 2,034,663 11.56 2015 Minimum Well-Capitalized Actual Amount Ratio Amount Ratio Amount Ratio Tier 1 Leverage Consolidated $ 751,798 4.00 % N/A N/A $ 1,790,034 9.52 % IBERIABANK 749,226 4.00 936,532 5.00 1,691,022 9.03 Common Equity Tier 1 (CET1) Consolidated $ 750,616 4.50 % N/A N/A $ 1,684,097 10.10 % IBERIABANK 748,667 4.50 1,081,408 6.50 1,691,022 10.16 Tier 1 Risk-Based Capital Consolidated $ 1,000,822 6.00 % N/A N/A $ 1,790,034 10.73 % IBERIABANK 998,223 6.00 1,330,964 8.00 1,691,022 10.16 Total Risk-Based Capital Consolidated $ 1,334,429 8.00 % N/A N/A $ 2,029,932 12.17 % IBERIABANK 1,330,964 8.00 1,663,705 10.00 1,843,545 11.08

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Schedule of Calculation of Basic and Diluted Earnings Per Share	The following table presents the calculation of basic and diluted earnings per share for the periods indicated. For the Years Ended December 31, (In thousands, except per share data) 2016 2015 2014 Earnings per common share - basic Net income $ 186,777 $ 142,844 $ 105,382 Preferred stock dividends (7,977 ) — — Dividends and undistributed earnings allocated to unvested restricted shares (1,872 ) (1,680 ) (1,651 ) Net income allocated to common shareholders - basic $ 176,928 $ 141,164 $ 103,731 Weighted average common shares outstanding 40,948 38,214 31,307 Earnings per common share - basic 4.32 3.69 3.31 Earnings per common share - diluted Net income allocated to common shareholders - basic $ 176,928 $ 141,164 $ 103,731 Dividends and undistributed earnings allocated to unvested restricted shares (37 ) (48 ) (34 ) Net income allocated to common shareholders - diluted $ 176,891 $ 141,116 $ 103,697 Weighted average common shares outstanding 40,948 38,214 31,307 Dilutive potential common shares 158 96 126 Weighted average common shares outstanding - diluted 41,106 38,310 31,433 Earnings per common share - diluted $ 4.30 $ 3.68 $ 3.30

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation Arrangements by Share-based Payment Award	The following table represents unvested restricted stock award and restricted share unit activity for the years ended December 31: 2016 2015 2014 Balance at beginning of period 507,130 506,289 523,756 Granted 254,276 207,575 168,254 Forfeited (28,855 ) (26,970 ) (18,171 ) Earned and issued (189,290 ) (179,764 ) (167,550 ) Balance at end of period 543,261 507,130 506,289 The following table represents the activity related to stock options during the periods indicated: Number of Shares Weighted Average Exercise Price Aggregate Intrinsic Value (Dollars in thousands) Weighted Average Remaining Contract Life (in years) Outstanding options, December 31, 2013 1,072,829 $ 53.47 Granted 77,434 65.31 Exercised (267,421 ) 48.57 $ 4,612 Forfeited or expired (15,160 ) 60.38 Outstanding options, December 31, 2014 867,682 $ 55.92 Granted 82,001 62.50 Exercised (119,917 ) 51.71 1,516 Forfeited or expired (15,989 ) 66.52 Outstanding options, December 31, 2015 813,777 $ 56.99 Granted 160,624 48.65 Exercised (196,769 ) 55.39 3,597 Forfeited or expired (56,094 ) 59.49 Outstanding options, December 31, 2016 721,538 $ 55.38 $ 20,583 6.0 Exercisable options, December 31, 2014 562,752 55.92 Exercisable options, December 31, 2015 546,842 $ 56.54 Exercisable options, December 31, 2016 415,376 $ 56.66 $ 11,366 4.4 The following table represents phantom stock award and performance unit activity during the periods indicated. (Dollars in thousands) Number of share equivalents (1) Value of share equivalents (2) Balance, December 31, 2013 433,884 $ 27,270 Granted 146,166 9,479 Forfeited share equivalents (22,800 ) 1,479 Vested share equivalents (81,903 ) 5,512 Balance, December 31, 2014 475,347 $ 30,826 Granted 167,573 9,228 Forfeited share equivalents (34,681 ) 1,910 Vested share equivalents (145,809 ) 9,288 Balance, December 31, 2015 462,430 $ 25,466 Granted 215,745 18,069 Forfeited share equivalents (42,051 ) 3,522 Vested share equivalents (163,294 ) 8,509 Balance, December 31, 2016 472,830 $ 39,600 (1) Number of share equivalents includes all reinvested dividend equivalents for the years indicated. (2) Except for share equivalents at the beginning of each period, which are based on the value at that time, and vested share payments, which are based on the cash paid at the time of vesting, the value of share equivalents is calculated based on the market price of the Company’s stock at the end of the respective periods. The market price of the Company’s stock was $83.75 , $55.07 and $64.85 on December 31, 2016, 2015 and 2014, respectively.
Schedule of Stock Option Activity by Exercise Price Range	The following table represents weighted average remaining life as of December 31, 2016 for options outstanding within the stated exercise prices: Options Outstanding Options Exercisable Exercise Price Range Per Share Number of Options Weighted Average Exercise Price Weighted Average Remaining Life Number of Options Weighted Average Exercise Price $36.48 to $47.50 147,913 $ 47.27 8.9 years 5,849 $ 45.42 $47.51 to $52.35 151,527 51.56 4.9 years 113,328 51.51 $52.36 to $54.82 116,558 53.39 4.6 years 90,653 53.68 $54.83 to $59.81 68,683 56.33 3.7 years 64,387 56.17 $59.82 to $62.82 154,506 61.32 5.7 years 98,688 60.63 $62.83 to $111.71 82,351 67.83 7.1 years 42,471 69.81 Total options 721,538 $ 55.38 6.0 years 415,376 $ 56.66
Schedule of Valuation Assumptions	The following weighted-average assumptions were used for option awards issued during the years ended December 31: 2016 2015 2014 Expected dividends 2.8 % 2.2 % 2.1 % Expected volatility 29.0 % 35.6 % 35.8 % Risk-free interest rate 1.4 % 2.0 % 2.3 % Expected term (in years) 6.5 7.5 7.5 Weighted-average grant-date fair value $ 10.46 $ 19.57 $ 21.26
Schedule of Allocation for Share-based Compensation Expense	The following table represents the compensation expense that is included in non-interest expense and related income tax benefits in the accompanying consolidated statements of comprehensive income related to stock options for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Compensation expense related to stock options $ 2,010 $ 1,861 $ 2,053 Income tax benefit related to stock options 331 317 375 The following table represents the compensation expense that was included in non-interest expense and related income tax benefits in the accompanying consolidated statements of comprehensive income related to restricted stock awards and restricted share units for the years ended December 31: (Dollars in thousands) 2016 2015 2014 Compensation expense related to restricted stock awards and restricted share units $ 12,513 $ 12,045 $ 9,932 Income tax benefit related to restricted stock awards and restricted share units 4,380 4,215 3,476 The following table indicates compensation expense recorded for phantom stock and performance units based on the number of share equivalents vested at December 31 of the years indicated and the current market price of the Company’s stock at that time: (Dollars in thousands) 2016 2015 2014 Compensation expense related to phantom stock and performance units $ 12,933 $ 12,109 $ 5,496

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Summary of Financial Instruments Outstanding	At December 31, 2016 and 2015, respectively, the Company had the following financial instruments outstanding and related reserves, whose contract amounts represent credit risk: (Dollars in thousands) 2016 2015 Commitments to grant loans $ 355,558 $ 61,240 Unfunded commitments under lines of credit 4,899,930 4,617,802 Commercial and standby letters of credit 163,560 150,281 Reserve for unfunded lending commitments 11,241 14,145

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Financial Asset and Liabilities Measured at Fair Value on Recurring Basis	The Company has segregated all financial assets and liabilities that are measured at fair value on a recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to estimate the fair value at the measurement date in the tables below. See Note 1, Summary of Significant Accounting Policies, for a description of how fair value measurements are determined. December 31, 2016 (Dollars in thousands) Level 1 Level 2 Level 3 Total Assets Securities available for sale $ — $ 3,446,097 $ — $ 3,446,097 Mortgage loans held for sale — 157,041 — 157,041 Derivative instruments — 38,886 — 38,886 Total $ — $ 3,642,024 $ — $ 3,642,024 Liabilities Derivative instruments $ — $ 30,209 $ — $ 30,209 Total $ — $ 30,209 $ — $ 30,209 December 31, 2015 Level 1 Level 2 Level 3 Total Assets Securities available for sale $ — $ 2,800,286 $ — $ 2,800,286 Mortgage loans held for sale — 166,247 — 166,247 Derivative instruments — 30,486 — 30,486 Total $ — $ 2,997,019 $ — $ 2,997,019 Liabilities Derivative instruments $ — $ 25,002 $ — $ 25,002 Total $ — $ 25,002 $ — $ 25,002
Gains and Losses Included in Earnings Related to Asset and Liabilities Measured at Fair Value on Recurring Basis	Gains and losses (realized and unrealized) included in earnings (or accumulated other comprehensive income) during 2016 related to assets and liabilities measured at fair value on a recurring basis are reported in non-interest income or other comprehensive income as follows: (Dollars in thousands) Non-interest income Other comprehensive income (loss), net of tax Total gains (losses) included in earnings $ 5,567 $ — Change in unrealized gains (losses) relating to assets still held at December 31, 2016 — (24,450 )
Financial Asset and Liabilities Measured at Fair Value on Nonrecurring Basis	The Company has segregated all assets and liabilities that are measured at fair value on a non-recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to determine the fair value at the measurement date in the tables below. December 31, 2016 (Dollars in thousands) Level 1 Level 2 Level 3 Total Assets Loans $ — $ — $ 93,485 $ 93,485 OREO, net — — 185 185 Total $ — $ — $ 93,670 $ 93,670 December 31, 2015 (Dollars in thousands) Level 1 Level 2 Level 3 Total Assets Loans $ — $ — $ 31,669 $ 31,669 OREO, net — — 1,662 1,662 Total $ — $ — $ 33,331 $ 33,331
Summary of Difference Between the Aggregate Fair Value and the Aggregate Unpaid Principal Balance for Mortgage Loans Held for Sale	The following table summarizes the difference between the aggregate fair value and the aggregate unpaid principal balance for mortgage loans held for sale measured at fair value: December 31, 2016 December 31, 2015 (Dollars in thousands) Aggregate Fair Value Aggregate Unpaid Principal Aggregate Fair Value Less Unpaid Principal Aggregate Fair Value Aggregate Unpaid Principal Aggregate Fair Value Less Unpaid Principal Mortgage loans held for sale, at fair value $ 157,041 $ 153,801 $ 3,240 $ 166,247 $ 161,083 $ 5,164

Fair Value of Financial Instr52

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Estimated Fair Values and Carrying Amounts of Financial Instruments	The carrying amount and estimated fair values, as well as the level within the fair value hierarchy, of the Company’s financial instruments are included in the tables below. See Note 1, Summary of Significant Accounting Policies, for a description of how fair value measurements are determined. December 31, 2016 (Dollars in thousands) Carrying Amount Fair Value Level 1 Level 2 Level 3 Financial Assets Cash and cash equivalents $ 1,362,126 $ 1,362,126 $ 1,362,126 $ — $ — Investment securities 3,535,313 3,536,029 — 3,536,029 — Loans and loans held for sale, net of unearned income and allowance for loan losses 15,077,293 15,066,055 — 157,041 14,909,014 FDIC loss share receivables — — — — — Derivative instruments 38,886 38,886 — 38,886 — Financial Liabilities Deposits $ 17,408,283 $ 16,762,475 $ — $ — $ 16,762,475 Short-term borrowings 509,136 509,136 334,136 175,000 — Long-term debt 628,953 617,656 — — 617,656 Derivative instruments 30,209 30,209 — 30,209 — December 31, 2015 (Dollars in thousands) Carrying Amount Fair Value Level 1 Level 2 Level 3 Financial Assets Cash and cash equivalents $ 510,267 $ 510,267 $ 510,267 $ — $ — Investment securities 2,899,214 2,901,247 — 2,901,247 — Loans and loans held for sale, net of unearned income and allowance for loan losses 14,355,297 14,674,749 — 166,247 14,508,502 FDIC loss share receivables 39,878 9,163 — — 9,163 Derivative instruments 30,486 30,486 — 30,486 — Financial Liabilities Deposits $ 16,178,748 $ 15,696,245 $ — $ — $ 15,696,245 Short-term borrowings 326,617 326,617 216,617 110,000 — Long-term debt 340,447 309,847 — — 309,847 Derivative instruments 25,002 25,002 — 25,002 —

Business Segments (Tables)

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Schedule of Segment Reporting Information	The following tables present certain information regarding our operations by reportable segment, including a reconciliation of segment results to reported consolidated results for the periods presented. Reconciling items between segment results and reported results include: • Elimination of interest income and interest expense representing interest earned by IBERIABANK on interest-bearing checking accounts held by related companies, as well as the elimination of the related deposit balances at the IBERIABANK segment; • Elimination of investment in subsidiary balances on certain operating segments included in total and average segment assets; and • Elimination of intercompany due to and due from balances on certain operating segments that are included in total and average segment assets. Year Ended December 31, 2016 (Dollars in thousands) IBERIABANK IMC LTC Consolidated Interest and dividend income $ 707,676 $ 9,261 $ 2 $ 716,939 Interest expense 64,068 3,633 — 67,701 Net interest income 643,608 5,628 2 649,238 Provision for loan losses 44,336 88 — 44,424 Mortgage income 405 83,448 — 83,853 Title revenue — — 22,213 22,213 Other non-interest income 127,751 4 — 127,755 Allocated expenses (13,972 ) 10,686 3,286 — Non-interest expense 484,099 65,133 17,433 566,665 Income before income tax expense 257,301 13,173 1,496 271,970 Income tax expense 79,565 5,023 605 85,193 Net income $ 177,736 $ 8,150 $ 891 $ 186,777 Total loans and loans held for sale, net of unearned income $ 15,004,360 $ 217,652 $ — $ 15,222,012 Total assets 21,319,267 315,057 24,866 21,659,190 Total deposits 17,402,742 5,541 — 17,408,283 Average assets 19,959,261 335,913 26,060 20,321,234 Year Ended December 31, 2015 (Dollars in thousands) IBERIABANK IMC LTC Consolidated Interest and dividend income $ 639,793 $ 7,062 $ 3 $ 646,858 Interest expense 56,222 2,878 — 59,100 Net interest income 583,571 4,184 3 587,758 Provision for loan losses 30,908 — — 30,908 Mortgage income 966 79,696 — 80,662 Title revenue — — 22,837 22,837 Other non-interest income 116,903 (2 ) (7 ) 116,894 Allocated expenses (16,253 ) 12,036 4,217 — Non-interest expense 495,158 57,784 17,363 570,305 Income before income tax expense 191,627 14,058 1,253 206,938 Income tax expense 58,006 5,581 507 64,094 Net income $ 133,621 $ 8,477 $ 746 $ 142,844 Total loans and loans held for sale, net of unearned income $ 14,305,663 $ 188,012 $ — $ 14,493,675 Total assets 19,220,085 256,888 27,095 19,504,068 Total deposits 16,173,831 4,917 — 16,178,748 Average assets 18,146,216 230,819 25,671 18,402,706 Year Ended December 31, 2014 (Dollars in thousands) IBERIABANK IMC LTC Consolidated Interest and dividend income $ 498,820 $ 5,992 $ 3 $ 504,815 Interest expense 42,983 1,721 — 44,704 Net interest income 455,837 4,271 3 460,111 Provision for loan losses 18,966 94 — 19,060 Mortgage income 71 51,726 — 51,797 Title revenue — — 20,492 20,492 Other non-interest income 101,401 (61 ) (1 ) 101,339 Allocated expenses (11,602 ) 8,203 3,399 — Non-interest expense 412,165 44,761 16,688 473,614 Income before income tax expense 137,780 2,878 407 141,065 Income tax expense 34,352 1,148 183 35,683 Net income $ 103,428 $ 1,730 $ 224 $ 105,382 Total loans and loans held for sale, net of unearned income $ 11,415,973 $ 165,143 $ — $ 11,581,116 Total assets 15,537,731 194,156 26,017 15,757,904 Total deposits 12,515,329 5,196 — 12,520,525 Average assets 14,430,768 176,003 25,223 14,631,994

Condensed Parent Company Only54

Condensed Parent Company Only Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Balance Sheets	Condensed Balance Sheets (Dollars in thousands) December 31 2016 2015 Assets Cash in bank $ 436,792 $ 154,298 Investments in subsidiaries 2,635,682 2,449,325 Other assets 40,423 54,454 $ 3,112,897 $ 2,658,077 Liabilities and Shareholders’ Equity Liabilities $ 173,203 $ 159,242 Shareholders’ equity 2,939,694 2,498,835 $ 3,112,897 $ 2,658,077
Condensed Statements of Income	Condensed Statements of Income Year Ended December 31 (Dollars in thousands) 2016 2015 2014 Operating income Reimbursement of management expenses $ 65,104 $ 59,255 $ 46,433 Other income 829 (329 ) 437 Total operating income 65,933 58,926 46,870 Operating expenses Interest expense 3,948 3,393 3,224 Salaries and employee benefits expense 45,623 41,689 31,981 Other expenses 19,566 17,492 14,576 Total operating expenses 69,137 62,574 49,781 Income (loss) before income tax benefit and increase in equity in undistributed earnings of subsidiaries (3,204 ) (3,648 ) (2,911 ) Income tax expense (benefit) 530 800 (518 ) Income (loss) before equity in undistributed earnings of subsidiaries (3,734 ) (4,448 ) (2,393 ) Equity in undistributed earnings of subsidiaries 190,511 147,292 107,775 Net Income 186,777 142,844 105,382 Preferred stock dividends (7,977 ) — — Net Income Available to Common Shareholders $ 178,800 $ 142,844 $ 105,382
Condensed Statements of Cash Flows	Condensed Statements of Cash Flows (Dollars in thousands) Year Ended December 31 2016 2015 2014 Cash Flow from Operating Activities Net income $ 186,777 $ 142,844 $ 105,382 Adjustments to reconcile net income to net cash provided by operating activities: Depreciation and amortization 98 416 595 Net income of subsidiaries (190,511 ) (147,292 ) (107,775 ) Share-based compensation cost 14,523 13,906 11,985 Gain on sale of assets — (110 ) — Tax benefit associated with share-based payment arrangements (1,122 ) (580 ) (2,105 ) Other operating activities, net 12,417 82,105 (27,274 ) Net Cash Provided by (Used in) Operating Activities 22,182 91,289 (19,192 ) Cash Flow from Investing Activities Cash paid in excess of cash received for acquisitions — (5,054 ) 4,783 Proceeds from sale of premises and equipment — 12 — Purchases of premises and equipment — (2 ) (36 ) Return of capital from (Capital contributed to) subsidiary (6,000 ) 5,000 (14,600 ) Other investing activities, net (749 ) — — Net Cash (Used in) Investing Activities (6,749 ) (44 ) (9,853 ) Cash Flow from Financing Activities Cash dividends paid on common stock (56,793 ) (52,318 ) (43,070 ) Cash dividends paid on preferred stock (7,028 ) — — Net share-based compensation stock transactions 6,899 1,915 7,966 Payments to repurchase common stock (11,666 ) — — Net proceeds from issuance of common stock 279,242 — — Net proceeds from issuance of preferred stock 55,285 76,812 — Tax benefit associated with share-based payment arrangements 1,122 580 2,105 Net Cash Provided by (Used In) Financing Activities 267,061 26,989 (32,999 ) Net Increase (Decrease) in Cash and Cash Equivalents 282,494 118,234 (62,044 ) Cash and Cash Equivalents at Beginning of Period 154,298 36,064 98,108 Cash and Cash Equivalents at End of Period $ 436,792 $ 154,298 $ 36,064

Summary of Significant Accoun55

Summary of Significant Accounting Policies (Detail) $ / shares in Units, $ in Thousands	Dec. 20, 2016USD ($)agreement	Dec. 31, 2016USD ($)State	Dec. 31, 2015USD ($)$ / shares
Schedule Of Significant Accounting Policies
Past due status period		30 days
Number of days due to be considered for accrual interest on loans discontinued		90 days
Number of loss share agreements terminated | agreement	12
Cash received upon termination of loss-share agreements	$ 6,500
FDIC indemnification assets derecognized	20,400
After tax loss on termination of loss-share agreements	$ 11,200
Maximum loss exposure related to unconsolidated VIE's		$ 84,000	$ 160,000
Fair value adjustment period following acquisition (in years)		1 year
Cash and cash equivalents maturity period (in years, less than)		3 months
Rate lock period (in days)		60 days
Property write-downs		$ 3,400	4,000
Other assets		$ 651,229	650,907
Past due loans threshold period		120 days
Additional provision expense, effect of change in method			$ 10,000
Additional provision expense, effect of change in method, (usd per share) | $ / shares			$ 0.17
Software and Software Development Costs
Schedule Of Significant Accounting Policies
Other assets		$ 5,600	$ 6,200
Minimum | Buildings
Schedule Of Significant Accounting Policies
Weighted average useful life (in years)		10 years
Minimum | Furniture, Fixtures and Equipment
Schedule Of Significant Accounting Policies
Weighted average useful life (in years)		3 years
Maximum | Customer relationship intangible asset
Schedule Of Significant Accounting Policies
Amortized intangible assets average life (in years)		10 years
Maximum | Buildings
Schedule Of Significant Accounting Policies
Weighted average useful life (in years)		40 years
Maximum | Furniture, Fixtures and Equipment
Schedule Of Significant Accounting Policies
Weighted average useful life (in years)		20 years
Weighted Average | Software and Software Development Costs
Schedule Of Significant Accounting Policies
Weighted average useful life (in years)		3 years
IBERIABANK Corporation
Schedule Of Significant Accounting Policies
Number of operating states | State		7
Other assets		$ 40,423	$ 54,454
IMC
Schedule Of Significant Accounting Policies
Number of operating states | State		10
Commercial Loans
Schedule Of Significant Accounting Policies
Past due loans threshold period		90 days
Residential and Consumer Portfolio Segment [Member]
Schedule Of Significant Accounting Policies
Period to evaluate loans for charge-off		120 days

Acquisition Activity (Detail)

Acquisition Activity (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2016
Business Acquisition
Maximum period for subject to change estimated fair values after acquisition date (in years)		1 year
Goodwill adjustments during the year		$ 2,253
Florida Bank Group Inc. and Old Florida Bancshares Inc.
Business Acquisition
Goodwill adjustments during the year	$ 2,300

Acquisition Activity - Schedule

Acquisition Activity - Schedule of Business Acquisitions (Detail) - USD ($) shares in Thousands, $ in Thousands	May 31, 2015	Mar. 31, 2015	Feb. 28, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Non-Equity consideration
Goodwill				$ 726,856	$ 724,603	$ 517,526
Florida Bank Group, Inc.
Equity consideration
Common stock issued (shares)			752,493
Total equity consideration			$ 47,497
Non-Equity consideration
Cash			42,988
Total consideration paid			90,485
Net assets acquired			73,043
Goodwill			$ 17,442
Old Florida Bancshares, Inc.
Equity consideration
Common stock issued (shares)		3,839,554
Total equity consideration		$ 242,007
Non-Equity consideration
Cash		11,145
Total consideration paid		253,152
Net assets acquired		152,375
Goodwill		$ 100,777
Georgia Commerce Bancshares Inc.
Equity consideration
Common stock issued (shares)	2,882,357
Total equity consideration	$ 185,249
Non-Equity consideration
Cash	5,015
Total consideration paid	190,264
Net assets acquired	103,569
Goodwill	$ 86,695

Acquisition Activity - Schedu58

Acquisition Activity - Schedule of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Jun. 30, 2016	May 31, 2015	Mar. 31, 2015	Feb. 28, 2015
Florida Bank Group, Inc.
Assets
Cash and cash equivalents		$ 72,982			$ 72,982
Investment securities		107,372			107,236
Loans		307,531			312,902
Other real estate owned		423			498
Core deposit intangible		4,489			0
Deferred tax asset, net		26,720			18,151
Other assets		20,868			29,817
Total Assets		540,385			541,586
Liabilities
Interest-bearing deposits		282,680			282,417
Non-interest-bearing deposits		109,548			109,548
Borrowings		68,598			60,000
Other liabilities		6,516			1,898
Total Liabilities		467,342			$ 453,863
Florida Bank Group, Inc. | Preliminary Fair Value Adjustment
Assets
Cash and cash equivalents		0
Investment securities		136
Loans		(5,371)
Other real estate owned		(75)
Core deposit intangible		4,489
Deferred tax asset, net		8,569
Other assets		(8,949)
Total Assets		(1,201)
Liabilities
Interest-bearing deposits		263
Non-interest-bearing deposits		0
Borrowings		8,598
Other liabilities		4,618
Total Liabilities		13,479
Old Florida Bancshares, Inc.
Assets
Cash and cash equivalents		360,688		$ 360,688
Investment securities		67,209		67,209
Loans held for sale		5,952		5,952
Loans		1,062,951		1,073,773
Other real estate owned		5,964		4,515
Core deposit intangible		6,821		0
Deferred tax asset, net		13,878		9,490
Other assets		23,311		30,549
Total Assets		1,546,774		1,552,176
Liabilities
Interest-bearing deposits		1,048,888		1,048,765
Non-interest-bearing deposits		340,869		340,869
Borrowings		1,528		1,528
Other liabilities		3,114		3,038
Total Liabilities		1,394,399		$ 1,394,200
Old Florida Bancshares, Inc. | Preliminary Fair Value Adjustment
Assets
Cash and cash equivalents		0
Investment securities		0
Loans held for sale		0
Loans		(10,822)
Other real estate owned		1,449
Core deposit intangible		6,821
Deferred tax asset, net		4,388
Other assets		(7,238)
Total Assets		(5,402)
Liabilities
Interest-bearing deposits		123
Non-interest-bearing deposits		0
Borrowings		0
Other liabilities		76
Total Liabilities		$ 199
Georgia Commerce Bancshares Inc.
Assets
Cash and cash equivalents	$ 51,059		$ 51,059
Investment securities	134,903		135,710
Loans held for sale	1,249		1,249
Loans	792,119		807,726
Other real estate owned	5,588		9,795
Core deposit intangible	6,720		0
Deferred tax asset, net	9,055		3,603
Other assets	28,299		28,956
Total Assets	1,028,992		1,038,098
Liabilities
Interest-bearing deposits	658,309		658,133
Non-interest-bearing deposits	249,739		249,739
Borrowings	13,204		13,204
Other liabilities	4,171		4,171
Total Liabilities	925,423		$ 925,247
Georgia Commerce Bancshares Inc. | Preliminary Fair Value Adjustment
Assets
Cash and cash equivalents	0
Investment securities	(807)
Loans held for sale	0
Loans	(15,607)
Other real estate owned	(4,207)
Core deposit intangible	6,720
Deferred tax asset, net	5,452
Other assets	(657)
Total Assets	(9,106)
Liabilities
Interest-bearing deposits	176
Non-interest-bearing deposits	0
Borrowings	0
Other liabilities	0
Total Liabilities	$ 176

Investment Securities - Schedul

Investment Securities - Schedule of Amortized Cost and Fair Values of Investment Securities, with Gross Unrealized Gains and Losses (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities
Amortized cost	$ 3,486,274	$ 2,803,430
Gross unrealized gain	7,374	15,477
Gross unrealized losses	(47,551)	(18,621)
Estimated fair value	3,446,097	2,800,286
Schedule of Held-to-maturity Securities
Amortized cost	89,216	98,928
Gross unrealized gains	1,666	2,910
Gross unrealized losses	(950)	(877)
Estimated fair value	89,932	100,961
Fair value of securities held as collateral	1,500,000	1,400,000
U.S. Government-Sponsored Enterprise Obligations
Schedule of Available-for-sale Securities
Amortized cost	212,662	252,514
Gross unrealized gain	245	1,161
Gross unrealized losses	(549)	(1,592)
Estimated fair value	212,358	252,083
Obligations of State and Political Subdivisions
Schedule of Available-for-sale Securities
Amortized cost	286,458	182,541
Gross unrealized gain	1,948	5,429
Gross unrealized losses	(5,207)	(9)
Estimated fair value	283,199	187,961
Schedule of Held-to-maturity Securities
Amortized cost	64,726	69,979
Gross unrealized gains	1,609	2,803
Gross unrealized losses	(133)	(101)
Estimated fair value	66,202	72,681
Mortgage-Backed Securities
Schedule of Available-for-sale Securities
Amortized cost	2,888,180	2,272,879
Gross unrealized gain	4,820	8,457
Gross unrealized losses	(41,291)	(16,523)
Estimated fair value	2,851,709	2,264,813
Schedule of Held-to-maturity Securities
Amortized cost	24,490	28,949
Gross unrealized gains	57	107
Gross unrealized losses	(817)	(776)
Estimated fair value	23,730	28,280
Other Securities
Schedule of Available-for-sale Securities
Amortized cost	98,974	95,496
Gross unrealized gain	361	430
Gross unrealized losses	(504)	(497)
Estimated fair value	$ 98,831	$ 95,429

Investment Securities - Sched60

Investment Securities - Schedule of Securities with Gross Unrealized Losses Aggregated by Investment Category (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Gross Unrealized Losses
Less than twelve months	$ (44,874)	$ (13,448)
Over twelve months	(2,677)	(5,173)
Total	(47,551)	(18,621)
Estimated Fair Value
Less than twelve months	2,526,660	1,515,493
Over twelve months	102,762	213,830
Total	2,629,422	1,729,323
Gross Unrealized Losses
Less than twelve months	(463)	(54)
Over twelve months	(487)	(823)
Total	(950)	(877)
Estimated Fair Value
Less than twelve months	22,890	5,529
Over twelve months	10,960	21,735
Total	33,850	27,264
U.S. Government-Sponsored Enterprise Obligations
Gross Unrealized Losses
Less than twelve months	(549)	(1,214)
Over twelve months	0	(378)
Total	(549)	(1,592)
Estimated Fair Value
Less than twelve months	150,554	177,839
Over twelve months	0	28,116
Total	150,554	205,955
Obligations of State and Political Subdivisions
Gross Unrealized Losses
Less than twelve months	(5,207)	(9)
Over twelve months	0	0
Total	(5,207)	(9)
Estimated Fair Value
Less than twelve months	148,059	5,765
Over twelve months	0	0
Total	148,059	5,765
Mortgage-Backed Securities
Gross Unrealized Losses
Less than twelve months	(38,667)	(11,737)
Over twelve months	(2,624)	(4,786)
Total	(41,291)	(16,523)
Estimated Fair Value
Less than twelve months	2,191,563	1,279,914
Over twelve months	98,912	185,215
Total	2,290,475	1,465,129
Other Securities
Gross Unrealized Losses
Less than twelve months	(451)	(488)
Over twelve months	(53)	(9)
Total	(504)	(497)
Estimated Fair Value
Less than twelve months	36,484	51,975
Over twelve months	3,850	499
Total	40,334	52,474
Obligations of State and Political Subdivisions
Gross Unrealized Losses
Less than twelve months	(133)	(9)
Over twelve months	0	(92)
Total	(133)	(101)
Estimated Fair Value
Less than twelve months	10,602	1,999
Over twelve months	0	4,162
Total	10,602	6,161
Mortgage-Backed Securities
Gross Unrealized Losses
Less than twelve months	(330)	(45)
Over twelve months	(487)	(731)
Total	(817)	(776)
Estimated Fair Value
Less than twelve months	12,288	3,530
Over twelve months	10,960	17,573
Total	$ 23,248	$ 21,103

Investment Securities - Additio

Investment Securities - Additional Information on Securities in a Continuous Loss Position (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)Security	Dec. 31, 2015USD ($)Security
Schedule of Available-for-sale Securities
Number of debt securities with unrealized losses | Security	252	397
Debt securities with unrealized losses (percentage of amortized cost)	1.79%	1.10%
Number of securities | Security	31	43
Amortized cost basis	$ 116,886	$ 241,561
Unrealized loss	$ 3,164	$ 5,996
Fannie Mae, Freddie Mac, or Ginnie Mae
Schedule of Available-for-sale Securities
Number of securities | Security	28	40
Amortized cost basis	$ 112,983	$ 236,800
Unrealized loss	$ 3,111	$ 5,895
Political Subdivisions
Schedule of Available-for-sale Securities
Number of securities | Security	0	2
Amortized cost basis	$ 0	$ 4,253
Unrealized loss	$ 0	$ 92
Other
Schedule of Available-for-sale Securities
Number of securities | Security	3	1
Amortized cost basis	$ 3,903	$ 508
Unrealized loss	$ 53	$ 9

Investment Securities - Sched62

Investment Securities - Schedule of Amortized Cost and Estimated Fair Value of Investment Securities by Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Weighted Average Yield
Within one year or less	2.29%
One through five years	1.65%
After five through ten years	2.25%
Over ten years	2.05%
Weighted average yield	2.06%
Amortized Cost
Within one year or less	$ 15,540
One through five years	283,914
After five through ten years	703,768
Over ten years	2,483,052
Amortized cost	3,486,274
Estimated Fair Value
Within one year or less	15,477
One through five years	284,150
After five through ten years	697,829
Over ten years	2,448,641
Estimated fair value	$ 3,446,097	$ 2,800,286
Weighted Average Yield
Within one year or less	2.59%
One through five years	2.95%
After five through ten years	3.07%
Over ten years	2.81%
Weighted average yield	2.88%
Amortized Cost
Within one year or less	$ 2,551
One through five years	9,903
After five through ten years	18,181
Over ten years	58,581
Amortized cost	89,216	98,928
Estimated Fair Value
Within one year or less	2,570
One through five years	10,082
After five through ten years	18,569
Over ten years	58,711
Estimated fair value	$ 89,932	$ 100,961

Investment Securities - Sched63

Investment Securities - Schedule of Realized Gains and Losses from Sale of Securities Classified as Available for Sale (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Realized gains	$ 2,949	$ 1,834	$ 863
Realized losses	(948)	(259)	(92)
Net realized gains (losses)	$ 2,001	$ 1,575	$ 771

Investment Securities - Sched64

Investment Securities - Schedule of Securities in Other Assets on Company's Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Federal Home Loan Bank (FHLB) stock	$ 42,326	$ 16,265
Federal Reserve Bank Stock	48,584	48,584
Other Investments	2,808	1,159
Marketable Securities, Equity Securities	$ 93,718	$ 66,008

Loans - Schedule of Non-Covered

Loans - Schedule of Non-Covered Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	$ 15,064,971	$ 14,327,428
Commercial Loans
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	10,906,581	10,198,855
Commercial Loans | Real Estate
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	6,802,266	6,073,511
Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	3,543,122	3,444,578
Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	561,193	680,766
Residential Mortgage
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	1,267,400	1,195,319
Consumer and Other Loans
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	2,890,990	2,933,254
Consumer and Other Loans | Home Equity
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	2,155,926	2,066,167
Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	131,052	246,298
Consumer and Other Loans | Other
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	604,012	620,789
Legacy Loans
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	12,694,924	11,190,520
Legacy Loans | Commercial Loans
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	9,377,399	8,133,341
Legacy Loans | Commercial Loans | Real Estate
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	5,623,314	4,504,062
Legacy Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	3,194,796	2,952,102
Legacy Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	559,289	677,177
Legacy Loans | Residential Mortgage
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	854,216	694,023
Legacy Loans | Consumer and Other Loans
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	2,463,309	2,363,156
Legacy Loans | Consumer and Other Loans | Home Equity
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	1,783,421	1,575,643
Legacy Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	131,048	246,214
Legacy Loans | Consumer and Other Loans | Other
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	548,840	541,299
Acquired Loans
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	2,370,047	3,136,908
Acquired Loans | Commercial Loans
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	1,529,182	2,065,514
Acquired Loans | Commercial Loans | Real Estate
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	1,178,952	1,569,449
Acquired Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	348,326	492,476
Acquired Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	1,904	3,589
Acquired Loans | Residential Mortgage
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	413,184	501,296
Acquired Loans | Consumer and Other Loans
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	427,681	570,098
Acquired Loans | Consumer and Other Loans | Home Equity
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	372,505	490,524
Acquired Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	4	84
Acquired Loans | Consumer and Other Loans | Other
Accounts, Notes, Loans and Financing Receivable
Total loans, net of unearned income	$ 55,172	$ 79,490

Loans (Detail)

Loans (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)bank	Dec. 31, 2015USD ($)
Accounts, Notes, Loans and Financing Receivable
Failed banks acquired | bank	6
Covered loans receivable	$ 0	$ 229,217
Deferred loan origination fees	22,600	18,700
Deposit liabilities reclassified as loans receivable	4,200	5,100
Loans with carrying value pledged to secure public deposits and other borrowings	$ 4,500,000	3,900,000
Carrying amounts of loans acquired		2,200,000
Covered Loan
Accounts, Notes, Loans and Financing Receivable
Covered loans receivable		229,200
Residential Mortgage and Home Equity | Covered Loan
Accounts, Notes, Loans and Financing Receivable
Covered loans receivable		$ 191,700

Loans - Schedule of Aging of Lo

Loans - Schedule of Aging of Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable
Acquired Impaired Loans	$ 306,426	$ 67,987	$ 14,036
Total Loans	$ 15,064,971	14,098,211
Past due loans threshold period	120 days
Commercial Loans
Accounts, Notes, Loans and Financing Receivable
Acquired Impaired Loans	$ 284,409	63,132	13,271
Past due loans threshold period	90 days
Residential Mortgage
Accounts, Notes, Loans and Financing Receivable
Acquired Impaired Loans	$ 4,627	70	0
Consumer and Other Loans
Accounts, Notes, Loans and Financing Receivable
Acquired Impaired Loans	17,390	4,785	$ 765
Acquired Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	4,249	5,357
Non-accrual Loans	6,958	5,421
Discount/Premium	(12,811)	(23,856)
Acquired Impaired Loans	530,186	724,719
Total Loans	2,370,047	3,136,908
Acquired Loans | Commercial Loans
Accounts, Notes, Loans and Financing Receivable
Total Loans	1,529,182	2,065,514
Acquired Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	0	297
Non-accrual Loans	1,946	0
Discount/Premium	(243)	(358)
Acquired Impaired Loans	32,991	56,320
Total Loans	61,408	125,426
Acquired Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	803	1,566
Non-accrual Loans	1,221	1,491
Discount/Premium	(3,649)	(4,479)
Acquired Impaired Loans	247,677	354,757
Total Loans	1,117,544	1,444,023
Acquired Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	124	623
Non-accrual Loans	1,317	1,154
Discount/Premium	(837)	(2,517)
Acquired Impaired Loans	32,732	50,762
Total Loans	348,326	492,476
Acquired Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Non-accrual Loans	0	170
Discount/Premium	(6)	2
Acquired Impaired Loans	0	1,231
Total Loans	1,904	3,589
Acquired Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	1,317	947
Non-accrual Loans	719	1,109
Discount/Premium	(1,835)	(6,601)
Acquired Impaired Loans	122,952	140,580
Total Loans	413,184	501,296
Acquired Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	1,517	1,329
Non-accrual Loans	1,395	1,291
Discount/Premium	(5,237)	(7,333)
Acquired Impaired Loans	88,419	114,130
Total Loans	372,505	490,524
Acquired Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Non-accrual Loans	0	0
Discount/Premium	0	0
Acquired Impaired Loans	4	65
Total Loans	4	84
Acquired Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Non-accrual Loans	0	0
Discount/Premium	0	0
Acquired Impaired Loans	0	582
Total Loans	468	582
Acquired Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	488	595
Non-accrual Loans	360	206
Discount/Premium	(1,004)	(2,570)
Acquired Impaired Loans	5,411	6,292
Total Loans	54,704	78,908
Legacy Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	26,006	20,733
Non-accrual Loans	221,543	50,928
Total Loans	12,694,924	11,190,520
Legacy Loans | Commercial Loans
Accounts, Notes, Loans and Financing Receivable
Total Loans	9,377,399	8,133,341
Legacy Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	0	801
Non-accrual Loans	0	120
Total Loans	740,761	636,481
Legacy Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	2,212	3,575
Non-accrual Loans	16,439	15,422
Total Loans	4,882,553	3,867,581
Legacy Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	4,869	2,034
Non-accrual Loans	31,227	6,659
Total Loans	3,194,796	2,952,102
Legacy Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	1,526	15
Non-accrual Loans	150,329	7,081
Total Loans	559,289	677,177
Legacy Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	4,693	4,002
Non-accrual Loans	13,014	13,674
Total Loans	854,216	694,023
Legacy Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	6,679	4,419
Non-accrual Loans	7,979	5,628
Total Loans	1,783,421	1,575,643
Legacy Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	2,956	2,705
Non-accrual Loans	1,038	1,181
Total Loans	131,048	246,214
Legacy Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	298	507
Non-accrual Loans	624	394
Total Loans	82,524	77,261
Legacy Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	2,773	2,675
Non-accrual Loans	893	769
Total Loans	466,316	464,038
Current or Less Than 30 days past due | Acquired Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	1,841,465	2,425,267
Current or Less Than 30 days past due | Acquired Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	26,714	69,167
Current or Less Than 30 days past due | Acquired Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	871,492	1,090,688
Current or Less Than 30 days past due | Acquired Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	314,990	442,454
Current or Less Than 30 days past due | Acquired Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	1,910	2,186
Current or Less Than 30 days past due | Acquired Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	290,031	365,261
Current or Less Than 30 days past due | Acquired Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	286,411	381,107
Current or Less Than 30 days past due | Acquired Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	0	19
Current or Less Than 30 days past due | Acquired Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	468	0
Current or Less Than 30 days past due | Acquired Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	49,449	74,385
Current or Less Than 30 days past due | Legacy Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	12,447,375	11,118,859
Current or Less Than 30 days past due | Legacy Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	740,761	635,560
Current or Less Than 30 days past due | Legacy Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	4,863,902	3,848,584
Current or Less Than 30 days past due | Legacy Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	3,158,700	2,943,409
Current or Less Than 30 days past due | Legacy Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	407,434	670,081
Current or Less Than 30 days past due | Legacy Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	836,509	676,347
Current or Less Than 30 days past due | Legacy Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	1,768,763	1,565,596
Current or Less Than 30 days past due | Legacy Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	127,054	242,328
Current or Less Than 30 days past due | Legacy Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	81,602	76,360
Current or Less Than 30 days past due | Legacy Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	462,650	460,594
30-59 days | Acquired Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	2,586	2,761
30-59 days | Acquired Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	0	180
30-59 days | Acquired Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	716	861
30-59 days | Acquired Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	73	623
30-59 days | Acquired Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
30-59 days | Acquired Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	328	7
30-59 days | Acquired Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	1,078	622
30-59 days | Acquired Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
30-59 days | Acquired Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
30-59 days | Acquired Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	391	468
30-59 days | Legacy Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	18,026	13,839
30-59 days | Legacy Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	0	801
30-59 days | Legacy Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	1,861	2,687
30-59 days | Legacy Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	3,999	1,208
30-59 days | Legacy Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	0	15
30-59 days | Legacy Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	2,012	1,075
30-59 days | Legacy Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	5,249	3,549
30-59 days | Legacy Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	2,551	2,187
30-59 days | Legacy Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	199	394
30-59 days | Legacy Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	2,155	1,923
60-89 days | Acquired Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	1,381	2,305
60-89 days | Acquired Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	0	117
60-89 days | Acquired Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	55	705
60-89 days | Acquired Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	51	0
60-89 days | Acquired Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
60-89 days | Acquired Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	989	940
60-89 days | Acquired Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	189	416
60-89 days | Acquired Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
60-89 days | Acquired Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
60-89 days | Acquired Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	97	127
60-89 days | Legacy Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	6,876	6,270
60-89 days | Legacy Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
60-89 days | Legacy Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	351	793
60-89 days | Legacy Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	870	739
60-89 days | Legacy Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	1,526	0
60-89 days | Legacy Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	1,577	2,485
60-89 days | Legacy Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	1,430	870
60-89 days | Legacy Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	405	518
60-89 days | Legacy Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	99	113
60-89 days | Legacy Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	618	752
Greater than 90 days | Acquired Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	282	291
Greater than 90 days | Acquired Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Acquired Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	32	0
Greater than 90 days | Acquired Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Acquired Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Acquired Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Acquired Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	250	291
Greater than 90 days | Acquired Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Acquired Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Acquired Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Legacy Loans
Accounts, Notes, Loans and Financing Receivable
Accruing	1,104	624
Greater than 90 days | Legacy Loans | Commercial Loans | Commercial real estate - Construction
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Legacy Loans | Commercial Loans | Commercial real estate - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	0	95
Greater than 90 days | Legacy Loans | Commercial Loans | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Accruing	0	87
Greater than 90 days | Legacy Loans | Commercial Loans | Energy-related
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Legacy Loans | Residential Mortgage | Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Accruing	1,104	442
Greater than 90 days | Legacy Loans | Consumer and Other Loans | Consumer - Home equity
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Legacy Loans | Consumer and Other Loans | Consumer - Indirect automobile
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Legacy Loans | Consumer and Other Loans | Consumer - Credit card
Accounts, Notes, Loans and Financing Receivable
Accruing	0	0
Greater than 90 days | Legacy Loans | Consumer and Other Loans | Consumer - Other
Accounts, Notes, Loans and Financing Receivable
Accruing	$ 0	$ 0

Loans - Schedule of Carrying Am

Loans - Schedule of Carrying Amount of Loans Acquired (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable
Carrying amounts of loans acquired		$ 2,200,000
Florida Bank Group, Inc.
Accounts, Notes, Loans and Financing Receivable
Acquired loans		300,000
Old Florida Bancshares, Inc.
Accounts, Notes, Loans and Financing Receivable
Acquired loans		1,100,000
Georgia Commerce
Accounts, Notes, Loans and Financing Receivable
Acquired loans		800,000
Loans Acquired Without Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable
Carrying amounts of loans acquired		2,100,000
Loans Acquired With Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable
Carrying amounts of loans acquired		$ 57,800
Florida Bank Group, Inc., Old Florida Bancshares, Inc., Georgia Commerce Bancshares, Inc. | ASC Topic 310-30
Accounts, Notes, Loans and Financing Receivable
Contractually required principal and interest at acquisition	$ 2,384,114
Expected losses and foregone interest	(15,539)
Cash flows expected to be collected at acquisition	2,368,575
Acquired loans at acquisition	2,105,466
Florida Bank Group, Inc., Old Florida Bancshares, Inc., Georgia Commerce Bancshares, Inc. | Acquired Impaired Loans | Receivables Acquired with Deteriorated Credit Quality
Accounts, Notes, Loans and Financing Receivable
Contractually required principal and interest at acquisition	76,445
Expected losses and foregone interest	(11,867)
Cash flows expected to be collected at acquisition	64,578
Accretable yield	(6,823)
Acquired loans at acquisition	$ 57,755

Loans - Summary of Changes in A

Loans - Summary of Changes in Accretable Yields of Acquired Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Balance at beginning of period	$ 227,502	$ 287,651	$ 354,892
Additions	0	6,823	13,848
Transfers from non-accretable difference to accretable yield	5,490	9,916	25,844
Accretion	(68,211)	(80,479)	(103,233)
Changes in expected cash flows not affecting non-accretable differences	10,273	3,591	(3,700)
Balance at end of period	$ 175,054	$ 227,502	$ 287,651

Loans - Schedule of Modified TD

Loans - Schedule of Modified TDRs (Detail) - Troubled Debt Restructurings - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Modifications
Extended maturities	$ 75,315	$ 15,594
Interest rate adjustment	193	0
Maturity and interest rate adjustment	2,470	23,374
Movement to or extension of interest-rate only payments	27,931	241
Forbearance	76,819	122
Other concession(s)	39,708	17,710
Total	222,436	57,041
Total TDRs	222,400	57,000
TDRs in accrual status	85,900	34,500
TDRs in non-accrual status	$ 136,500	$ 22,500

Loans - Schedule of Subsequentl

Loans - Schedule of Subsequently Defaulted TDRs (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)SecurityLoan	Dec. 31, 2015USD ($)SecurityLoan
Accounts, Notes, Loans and Financing Receivable
Threshold period for loans in default (in days)	30 days
Non-Covered TDRs | TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of loans | SecurityLoan	523	113
Pre-modification outstanding recorded investment	$ 223,640	$ 62,631
Post-modification outstanding recorded investment	$ 222,436	$ 57,041
Number of loans | SecurityLoan	124	62
Recorded investment	$ 21,225	$ 35,793
Non-Covered TDRs | Commercial Loans | Real Estate | TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of loans | SecurityLoan	44	11
Pre-modification outstanding recorded investment	$ 30,844	$ 26,764
Post-modification outstanding recorded investment	$ 24,997	$ 25,250
Number of loans | SecurityLoan	9	6
Recorded investment	$ 467	$ 22,075
Non-Covered TDRs | Commercial Loans | Commercial and industrial | TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of loans | SecurityLoan	59	26
Pre-modification outstanding recorded investment	$ 36,379	$ 21,233
Post-modification outstanding recorded investment	$ 34,415	$ 18,114
Number of loans | SecurityLoan	21	20
Recorded investment	$ 12,996	$ 8,970
Non-Covered TDRs | Commercial Loans | Energy-related | TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of loans | SecurityLoan	24	2
Pre-modification outstanding recorded investment	$ 133,933	$ 9,797
Post-modification outstanding recorded investment	$ 141,848	$ 9,484
Number of loans | SecurityLoan	2	1
Recorded investment	$ 5,034	$ 3,120
Non-Covered TDRs | Residential Mortgage | Residential mortgage | TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of loans | SecurityLoan	43	1
Pre-modification outstanding recorded investment	$ 5,141	$ 70
Post-modification outstanding recorded investment	$ 4,946	$ 68
Number of loans | SecurityLoan	8	0
Recorded investment	$ 405	$ 0
Non-Covered TDRs | Consumer and Other Loans | Consumer - Home equity | TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of loans | SecurityLoan	158	50
Pre-modification outstanding recorded investment	$ 13,273	$ 4,440
Post-modification outstanding recorded investment	$ 12,568	$ 3,865
Number of loans | SecurityLoan	25	20
Recorded investment	$ 1,379	$ 1,547
Non-Covered TDRs | Consumer and Other Loans | Consumer - Indirect Automobile | TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of loans | SecurityLoan	79	6
Pre-modification outstanding recorded investment	$ 983	$ 79
Post-modification outstanding recorded investment	$ 792	$ 79
Number of loans | SecurityLoan	37	6
Recorded investment	$ 338	$ 79
Non-Covered TDRs | Consumer and Other Loans | Consumer - Other | TDRs Occurring during the Period
Accounts, Notes, Loans and Financing Receivable
Number of loans | SecurityLoan	116	17
Pre-modification outstanding recorded investment	$ 3,087	$ 248
Post-modification outstanding recorded investment	$ 2,870	$ 181
Number of loans | SecurityLoan	22	9
Recorded investment	$ 606	$ 2

Allowance for Credit Losses a72

Allowance for Credit Losses and Credit Quality - Schedule of Allowance for Loan Losses for Covered and Non-Covered Loan Portfolios (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for credit losses
Allowance for loan losses at beginning of period	$ 138,378	$ 130,131	$ 143,074
Provision for loan losses before benefit attributable to FDIC loss share agreements	42,927	29,548	14,800
Adjustment attributable to FDIC loss share arrangements	(1,497)	(1,360)	(4,260)
Net provision for loan losses	44,424	30,908	19,060
Transfer of balance to OREO and other	(2,781)	(10,419)	(22,157)
Loans charged off	(39,839)	(17,301)	(11,983)
Recoveries	6,034	6,419	6,397
Allowance for loan losses at end of period	144,719	138,378	130,131
Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	14,145	11,801	11,147
Provision for (Reversal of) unfunded lending commitments	(2,904)	2,344	654
Reserve for unfunded commitments at end of period	11,241	14,145	11,801
Allowance for credit losses at end of period	155,960	152,523	141,932
Legacy Loans
Allowance for credit losses
Allowance for loan losses at beginning of period	93,808	76,174	67,342
Provision for loan losses before benefit attributable to FDIC loss share agreements	44,791	27,711	14,274
Adjustment attributable to FDIC loss share arrangements	0	0	0
Net provision for loan losses	44,791	27,711	14,274
Transfer of balance to OREO and other	(9)	0	0
Loans charged off	(38,055)	(15,778)	(11,312)
Recoveries	5,034	5,701	5,870
Allowance for loan losses at end of period	105,569	93,808	76,174
Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	14,145	11,801	11,147
Provision for (Reversal of) unfunded lending commitments	(2,904)	2,344	654
Reserve for unfunded commitments at end of period	11,241	14,145	11,801
Allowance for credit losses at end of period	116,810	107,953	87,975
Acquired Loans
Allowance for credit losses
Allowance for loan losses at beginning of period	44,570	53,957	75,732
Provision for loan losses before benefit attributable to FDIC loss share agreements	(1,864)	1,837	526
Adjustment attributable to FDIC loss share arrangements	(1,497)	(1,360)	(4,260)
Net provision for loan losses	(367)	3,197	4,786
Transfer of balance to OREO and other	(2,772)	(10,419)	(22,157)
Loans charged off	(1,784)	(1,523)	(671)
Recoveries	1,000	718	527
Allowance for loan losses at end of period	39,150	44,570	53,957
Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	0	0	0
Provision for (Reversal of) unfunded lending commitments	0	0	0
Reserve for unfunded commitments at end of period	0	0	0
Allowance for credit losses at end of period	$ 39,150	$ 44,570	$ 53,957

Allowance for Credit Losses a73

Allowance for Credit Losses and Credit Quality - Schedule of Allowance for Loan Losses for Legacy and Acquired Loans, by Loan Portfolio (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	$ 138,378	$ 130,131	$ 143,074
Transfer of balance to OREO and other	(2,781)	(10,419)	(22,157)
Loans charged off	(39,839)	(17,301)	(11,983)
Recoveries	6,034	6,419	6,397
Allowance for loan losses at end of period	144,719	138,378	130,131
Financing Receivable, Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	14,145	11,801	11,147
Reserve for unfunded commitments at end of period	11,241	14,145	11,801
Loans, net of unearned income:
Loans, net of unearned income	0	229,217
Legacy Loans
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	93,808	76,174	67,342
Provision for (Reversal of) loan losses	44,791	27,711	14,274
Transfer of balance to OREO and other	(9)	0	0
Loans charged off	(38,055)	(15,778)	(11,312)
Recoveries	5,034	5,701	5,870
Allowance for loan losses at end of period	105,569	93,808	76,174
Financing Receivable, Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	14,145	11,801	11,147
Provision for (Reversal of) unfunded commitments	(2,904)	2,344	654
Reserve for unfunded commitments at end of period	11,241	14,145	11,801
Allowance on loans individually evaluated for impairment	22,776	3,993	430
Allowance on loans collectively evaluated for impairment	82,793	89,815	75,744
Loans, net of unearned income:
Loans, net of unearned income	12,694,924	11,190,520	9,668,714
Balance at end of period individually evaluated for impairment	292,645	66,641	11,700
Balance at end of period collectively evaluated for impairment	12,402,279	11,123,879	9,657,014
Legacy Loans | Commercial Loans | Real Estate
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	24,658	26,752	22,872
Provision for (Reversal of) loan losses	4,042	(1,466)	2,171
Transfer of balance to OREO and other	0
Loans charged off	(4,316)	(2,525)	(1,164)
Recoveries	1,024	1,897	2,873
Allowance for loan losses at end of period	25,408	24,658	26,752
Financing Receivable, Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	4,160	3,370	3,071
Provision for (Reversal of) unfunded commitments	(954)	790	299
Reserve for unfunded commitments at end of period	3,206	4,160	3,370
Allowance on loans individually evaluated for impairment	641	1,246	20
Allowance on loans collectively evaluated for impairment	24,767	23,412	26,732
Loans, net of unearned income:
Loans, net of unearned income	5,623,314	4,504,062	3,676,811
Balance at end of period individually evaluated for impairment	34,031	28,857	7,036
Balance at end of period collectively evaluated for impairment	5,589,283	4,475,205	3,669,775
Legacy Loans | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	23,283	24,455	20,839
Provision for (Reversal of) loan losses	15,476	(103)	4,971
Transfer of balance to OREO and other	0
Loans charged off	(3,720)	(1,276)	(1,400)
Recoveries	395	207	45
Allowance for loan losses at end of period	35,434	23,283	24,455
Financing Receivable, Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	3,448	3,733	1,814
Provision for (Reversal of) unfunded commitments	87	(285)	1,919
Reserve for unfunded commitments at end of period	3,535	3,448	3,733
Allowance on loans individually evaluated for impairment	10,864	272	407
Allowance on loans collectively evaluated for impairment	24,570	23,011	24,048
Loans, net of unearned income:
Loans, net of unearned income	3,194,796	2,952,102	2,452,521
Balance at end of period individually evaluated for impairment	41,518	20,086	3,965
Balance at end of period collectively evaluated for impairment	3,153,278	2,932,016	2,448,556
Legacy Loans | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	23,863	5,949	6,878
Provision for (Reversal of) loan losses	14,776	17,917	(929)
Transfer of balance to OREO and other	0
Loans charged off	(16,993)	(3)	0
Recoveries	840	0	0
Allowance for loan losses at end of period	22,486	23,863	5,949
Financing Receivable, Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	2,665	1,596	3,043
Provision for (Reversal of) unfunded commitments	(1,662)	1,069	(1,447)
Reserve for unfunded commitments at end of period	1,003	2,665	1,596
Allowance on loans individually evaluated for impairment	9,769	2,122	0
Allowance on loans collectively evaluated for impairment	12,717	21,741	5,949
Loans, net of unearned income:
Loans, net of unearned income	559,289	677,177	872,866
Balance at end of period individually evaluated for impairment	196,327	13,020	0
Balance at end of period collectively evaluated for impairment	362,962	664,157	872,866
Legacy Loans | Residential Mortgage
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	3,947	2,678	2,546
Provision for (Reversal of) loan losses	64	1,493	566
Transfer of balance to OREO and other	(9)
Loans charged off	(313)	(291)	(578)
Recoveries	146	67	144
Allowance for loan losses at end of period	3,835	3,947	2,678
Financing Receivable, Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	830	168	72
Provision for (Reversal of) unfunded commitments	(173)	662	96
Reserve for unfunded commitments at end of period	657	830	168
Allowance on loans individually evaluated for impairment	144	1	0
Allowance on loans collectively evaluated for impairment	3,691	3,946	2,678
Loans, net of unearned income:
Loans, net of unearned income	854,216	694,023	527,694
Balance at end of period individually evaluated for impairment	4,312	70	0
Balance at end of period collectively evaluated for impairment	849,904	693,953	527,694
Legacy Loans | Consumer and Other Loans
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	18,057	16,340	14,207
Provision for (Reversal of) loan losses	10,433	9,870	7,495
Transfer of balance to OREO and other	0
Loans charged off	(12,713)	(11,683)	(8,170)
Recoveries	2,629	3,530	2,808
Allowance for loan losses at end of period	18,406	18,057	16,340
Financing Receivable, Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	3,042	2,934	3,147
Provision for (Reversal of) unfunded commitments	(202)	108	(213)
Reserve for unfunded commitments at end of period	2,840	3,042	2,934
Allowance on loans individually evaluated for impairment	1,358	352	3
Allowance on loans collectively evaluated for impairment	17,048	17,705	16,337
Loans, net of unearned income:
Loans, net of unearned income	2,463,309	2,363,156	2,138,822
Balance at end of period individually evaluated for impairment	16,457	4,608	699
Balance at end of period collectively evaluated for impairment	2,446,852	2,358,548	2,138,123
Acquired Loans
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	44,570	53,957	75,732
Provision for (Reversal of) loan losses	(367)	3,197	4,786
Increase (Decrease) in FDIC loss share receivable	(1,497)	(1,360)	(4,260)
Transfer of balance to OREO and other	(2,772)	(10,419)	(22,157)
Loans charged off	(1,784)	(1,523)	(671)
Recoveries	1,000	718	527
Allowance for loan losses at end of period	39,150	44,570	53,957
Financing Receivable, Reserve For Unfunded Commitments
Reserve for unfunded commitments at beginning of period	0	0	0
Reserve for unfunded commitments at end of period	0	0	0
Allowance on loans individually evaluated for impairment	1,517	86	0
Allowance on loans collectively evaluated for impairment	37,633	44,484	53,957
Loans, net of unearned income:
Loans, net of unearned income	2,370,047	3,136,908	1,772,330
Balance at end of period individually evaluated for impairment	10,135	1,342	0
Balance at end of period collectively evaluated for impairment	1,829,726	2,410,847	905,179
Acquired Loans | Commercial Loans | Real Estate
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	25,979	29,949	42,026
Provision for (Reversal of) loan losses	(1,598)	2,182	665
Increase (Decrease) in FDIC loss share receivable	(34)	757	227
Transfer of balance to OREO and other	(868)	(6,849)	(13,117)
Loans charged off	(22)	(281)	0
Recoveries	117	221	148
Allowance for loan losses at end of period	23,574	25,979	29,949
Financing Receivable, Reserve For Unfunded Commitments
Allowance on loans individually evaluated for impairment	737		0
Allowance on loans collectively evaluated for impairment	22,837	25,979	29,949
Loans, net of unearned income:
Loans, net of unearned income	1,178,952	1,569,449	684,968
Balance at end of period individually evaluated for impairment	8,246	720	0
Balance at end of period collectively evaluated for impairment	890,038	1,157,652	169,338
Acquired Loans | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	2,819	3,265	6,641
Provision for (Reversal of) loan losses	1,645	(122)	536
Increase (Decrease) in FDIC loss share receivable	(50)	(49)	509
Transfer of balance to OREO and other	(519)	(275)	(4,421)
Loans charged off	(932)	0	0
Recoveries	267	0	0
Allowance for loan losses at end of period	3,230	2,819	3,265
Financing Receivable, Reserve For Unfunded Commitments
Allowance on loans individually evaluated for impairment	780	41	0
Allowance on loans collectively evaluated for impairment	2,450	2,778	3,265
Loans, net of unearned income:
Loans, net of unearned income	348,326	492,476	119,174
Balance at end of period individually evaluated for impairment	1,879	164	0
Balance at end of period collectively evaluated for impairment	313,715	441,550	60,584
Acquired Loans | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	125	51	0
Provision for (Reversal of) loan losses	(86)	74	51
Increase (Decrease) in FDIC loss share receivable	0	0	0
Transfer of balance to OREO and other	0	0	0
Loans charged off	0	0	0
Recoveries	0	0	0
Allowance for loan losses at end of period	39	125	51
Financing Receivable, Reserve For Unfunded Commitments
Allowance on loans individually evaluated for impairment	0	0	0
Allowance on loans collectively evaluated for impairment	39	125	51
Loans, net of unearned income:
Loans, net of unearned income	1,904	3,589	7,742
Balance at end of period individually evaluated for impairment	0	0	0
Balance at end of period collectively evaluated for impairment	1,904	2,358	7,742
Acquired Loans | Residential Mortgage
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	7,841	6,484	10,889
Provision for (Reversal of) loan losses	759	2,126	1,296
Increase (Decrease) in FDIC loss share receivable	(1,090)	(235)	(3,854)
Transfer of balance to OREO and other	(132)	(491)	(1,914)
Loans charged off	0	(71)	(35)
Recoveries	34	28	102
Allowance for loan losses at end of period	7,412	7,841	6,484
Financing Receivable, Reserve For Unfunded Commitments
Allowance on loans individually evaluated for impairment	0	0	0
Allowance on loans collectively evaluated for impairment	7,412	7,841	6,484
Loans, net of unearned income:
Loans, net of unearned income	413,184	501,296	552,603
Balance at end of period individually evaluated for impairment	0	0	0
Balance at end of period collectively evaluated for impairment	290,232	360,716	402,347
Acquired Loans | Consumer and Other Loans
Financing Receivable, Allowance for Credit Losses
Allowance for loan losses at beginning of period	7,806	14,208	16,176
Provision for (Reversal of) loan losses	(1,087)	(1,063)	2,238
Increase (Decrease) in FDIC loss share receivable	(323)	(1,833)	(1,142)
Transfer of balance to OREO and other	(1,253)	(2,804)	(2,705)
Loans charged off	(830)	(1,171)	(636)
Recoveries	582	469	277
Allowance for loan losses at end of period	4,895	7,806	14,208
Financing Receivable, Reserve For Unfunded Commitments
Allowance on loans individually evaluated for impairment	0	45	0
Allowance on loans collectively evaluated for impairment	4,895	7,761	14,208
Loans, net of unearned income:
Loans, net of unearned income	427,681	570,098	407,843
Balance at end of period individually evaluated for impairment	10	458	0
Balance at end of period collectively evaluated for impairment	333,837	448,571	265,168
Receivables Acquired with Deteriorated Credit Quality | Acquired Loans
Loans, net of unearned income:
Balance at end of period acquired with deteriorated credit quality	530,186	724,719	867,151
Receivables Acquired with Deteriorated Credit Quality | Acquired Loans | Commercial Loans | Real Estate
Loans, net of unearned income:
Balance at end of period acquired with deteriorated credit quality	280,668	411,077	515,630
Receivables Acquired with Deteriorated Credit Quality | Acquired Loans | Commercial Loans | Commercial and industrial
Loans, net of unearned income:
Balance at end of period acquired with deteriorated credit quality	32,732	50,762	58,590
Receivables Acquired with Deteriorated Credit Quality | Acquired Loans | Commercial Loans | Energy-related
Loans, net of unearned income:
Balance at end of period acquired with deteriorated credit quality	0	1,231	0
Receivables Acquired with Deteriorated Credit Quality | Acquired Loans | Residential Mortgage
Loans, net of unearned income:
Balance at end of period acquired with deteriorated credit quality	122,952	140,580	150,256
Receivables Acquired with Deteriorated Credit Quality | Acquired Loans | Consumer and Other Loans
Loans, net of unearned income:
Balance at end of period acquired with deteriorated credit quality	$ 93,834	$ 121,069	$ 142,675

Allowance for Credit Losses a74

Allowance for Credit Losses and Credit Quality - Investment in Legacy and Acquired Loans by Credit Quality Indicator (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	$ (22,600)	$ (18,700)
Total Loans	15,064,971	14,098,211
Acquired Loans
Financing Receivable, Allowance for Credit Losses
Total Loans	2,370,047	3,136,908
Acquired Loans | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(38,153)	(60,088)
Total Loans	1,529,182	2,065,514
Acquired Loans | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	8,759	10,107
Total Loans	61,408	125,426
Acquired Loans | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(42,419)	(63,295)
Total Loans	1,117,544	1,444,023
Acquired Loans | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(4,487)	(6,900)
Total Loans	348,326	492,476
Acquired Loans | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(6)	0
Total Loans	1,904	3,589
Acquired Loans | Residential and Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(53,753)	(60,768)
Current	859,474	1,089,542
30 or more days past due	35,144	42,620
Total Loans	840,865	1,071,394
Acquired Loans | Residential Mortgage | Residential mortgage
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(32,030)	(29,559)
Current	424,300	506,103
30 or more days past due	20,914	24,752
Total Loans	413,184	501,296
Acquired Loans | Consumer and Other Loans | Consumer - Home equity
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(17,323)	(29,492)
Current	377,021	503,635
30 or more days past due	12,807	16,381
Total Loans	372,505	490,524
Acquired Loans | Consumer and Other Loans | Consumer - Indirect Automobile
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(8)	0
Current	12	72
30 or more days past due	0	12
Total Loans	4	84
Acquired Loans | Consumer and Other Loans | Consumer - Credit Card
Financing Receivable, Allowance for Credit Losses
Total Loans	468	582
Acquired Loans | Consumer and Other Loans | Consumer - Other
Financing Receivable, Allowance for Credit Losses
Premium/(Discount)	(4,392)	(1,717)
Current	58,141	79,732
30 or more days past due	1,423	1,475
Total Loans	55,172	79,490
Acquired Loans | Consumer and Other Loans | Consumer - Other
Financing Receivable, Allowance for Credit Losses
Total Loans	54,704	78,908
Acquired Loans | Pass | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	1,461,625	1,975,355
Acquired Loans | Pass | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	46,498	104,064
Acquired Loans | Pass | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	1,090,063	1,395,884
Acquired Loans | Pass | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	323,154	473,241
Acquired Loans | Pass | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	1,910	2,166
Acquired Loans | Special Mention | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	21,159	36,192
Acquired Loans | Special Mention | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	459	1,681
Acquired Loans | Special Mention | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	19,284	26,080
Acquired Loans | Special Mention | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	1,416	8,376
Acquired Loans | Special Mention | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	0	55
Acquired Loans | Substandard | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	80,003	104,602
Acquired Loans | Substandard | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	3,118	8,803
Acquired Loans | Substandard | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	49,136	79,119
Acquired Loans | Substandard | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	27,749	16,510
Acquired Loans | Substandard | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	0	170
Acquired Loans | Doubtful | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	4,525	9,299
Acquired Loans | Doubtful | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	2,574	771
Acquired Loans | Doubtful | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	1,457	6,124
Acquired Loans | Doubtful | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	494	1,206
Acquired Loans | Doubtful | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	0	1,198
Acquired Loans | Loss | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	23	154
Acquired Loans | Loss | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	0	0
Acquired Loans | Loss | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	23	111
Acquired Loans | Loss | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	0	43
Acquired Loans | Loss | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	0	0
Legacy Loans
Financing Receivable, Allowance for Credit Losses
Total Loans	12,694,924	11,190,520
Legacy Loans | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Total Loans	9,377,399	8,133,341
Legacy Loans | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Total Loans	740,761	636,481
Legacy Loans | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Total Loans	4,882,553	3,867,581
Legacy Loans | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Total Loans	3,194,796	2,952,102
Legacy Loans | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Total Loans	559,289	677,177
Legacy Loans | Residential and Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Losses
Current	3,276,578	3,021,225
30 or more days past due	40,947	35,954
Total Loans	3,317,525	3,057,179
Legacy Loans | Residential Mortgage | Residential mortgage
Financing Receivable, Allowance for Credit Losses
Current	836,509	676,347
30 or more days past due	17,707	17,676
Total Loans	854,216	694,023
Legacy Loans | Consumer and Other Loans | Consumer - Home equity
Financing Receivable, Allowance for Credit Losses
Current	1,768,763	1,565,596
30 or more days past due	14,658	10,047
Total Loans	1,783,421	1,575,643
Legacy Loans | Consumer and Other Loans | Consumer - Indirect Automobile
Financing Receivable, Allowance for Credit Losses
Current	127,054	242,328
30 or more days past due	3,994	3,886
Total Loans	131,048	246,214
Legacy Loans | Consumer and Other Loans | Consumer - Credit Card
Financing Receivable, Allowance for Credit Losses
Current	81,602	76,360
30 or more days past due	922	901
Total Loans	82,524	77,261
Legacy Loans | Consumer and Other Loans | Consumer - Other
Financing Receivable, Allowance for Credit Losses
Current	462,650	460,594
30 or more days past due	3,666	3,444
Total Loans	466,316	464,038
Legacy Loans | Pass | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	8,890,604	7,884,470
Legacy Loans | Pass | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	734,687	634,889
Legacy Loans | Pass | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	4,801,494	3,806,528
Legacy Loans | Pass | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	3,112,300	2,911,396
Legacy Loans | Pass | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	242,123	531,657
Legacy Loans | Special Mention | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	138,209	104,800
Legacy Loans | Special Mention | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	2,203	160
Legacy Loans | Special Mention | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	26,159	21,877
Legacy Loans | Special Mention | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	29,763	14,826
Legacy Loans | Special Mention | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	80,084	67,937
Legacy Loans | Substandard | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	319,694	132,593
Legacy Loans | Substandard | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	3,871	1,432
Legacy Loans | Substandard | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	54,900	37,001
Legacy Loans | Substandard | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	35,199	19,888
Legacy Loans | Substandard | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	225,724	74,272
Legacy Loans | Doubtful | Commercial Loans
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	28,892	11,478
Legacy Loans | Doubtful | Commercial Loans | Commercial Real Estate - Construction
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	0	0
Legacy Loans | Doubtful | Commercial Loans | Commercial Real Estate - Other
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	0	2,175
Legacy Loans | Doubtful | Commercial Loans | Commercial and industrial
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	17,534	5,992
Legacy Loans | Doubtful | Commercial Loans | Energy-related
Financing Receivable, Allowance for Credit Losses
Loans and Leases Receivable before Fees, Gross	$ 11,358	$ 3,311

Allowance for Credit Losses a75

Allowance for Credit Losses and Credit Quality - Schedule of Investment in Legacy Impaired Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired
Acquired Impaired Loans	$ 306,426	$ 67,987	$ 14,036
Unpaid principal balance	292,645	66,641	11,700
Related allowance	(22,776)	(3,993)	(430)
Average recorded investment	261,850	70,714	12,246
Interest income recognized	8,680	2,868	239
Commercial Loans
Financing Receivable, Impaired
Acquired Impaired Loans	284,409	63,132	13,271
Unpaid principal balance	271,876	61,963	11,001
Related allowance	(21,274)	(3,640)	(427)
Average recorded investment	244,821	67,562	11,532
Interest income recognized	7,934	2,760	218
Residential Mortgage
Financing Receivable, Impaired
Acquired Impaired Loans	4,627	70	0
Unpaid principal balance	4,312	70	0
Related allowance	(144)	(1)	0
Average recorded investment	4,377	70	0
Interest income recognized	161	5	0
Consumer and Other Loans
Financing Receivable, Impaired
Acquired Impaired Loans	17,390	4,785	765
Unpaid principal balance	16,457	4,608	699
Related allowance	(1,358)	(352)	(3)
Average recorded investment	12,652	3,082	714
Interest income recognized	585	103	21
With No Related Allowance Recorded | Commercial Loans | Real Estate
Financing Receivable, Impaired
Acquired Impaired Loans	17,299	17,002	7,615
Unpaid principal balance	16,507	16,145	6,680
Average recorded investment	21,133	15,864	6,703
Interest income recognized	948	315	132
With No Related Allowance Recorded | Commercial Loans | Commercial and industrial
Financing Receivable, Impaired
Acquired Impaired Loans	14,202	14,571	3,710
Unpaid principal balance	13,189	14,340	2,483
Average recorded investment	15,492	18,839	2,602
Interest income recognized	805	1,148	39
With No Related Allowance Recorded | Commercial Loans | Energy-related
Financing Receivable, Impaired
Acquired Impaired Loans	152,424	0
Unpaid principal balance	143,239	0
Average recorded investment	114,623	0
Interest income recognized	2,903	0
With No Related Allowance Recorded | Consumer and Other Loans | Consumer - Home equity
Financing Receivable, Impaired
Acquired Impaired Loans	0	730	748
Unpaid principal balance	0	730	682
Average recorded investment	0	533	696
Interest income recognized	0	22	19
With No Related Allowance Recorded | Consumer and Other Loans | Consumer - Other
Financing Receivable, Impaired
Acquired Impaired Loans	0	66
Unpaid principal balance	0	66
Average recorded investment	0	66
Interest income recognized	0	5
With An Allowance Recorded | Commercial Loans | Real Estate
Financing Receivable, Impaired
Acquired Impaired Loans	17,688	12,765	356
Unpaid principal balance	17,524	12,712	356
Related allowance	(641)	(1,246)	(20)
Average recorded investment	16,771	12,985	378
Interest income recognized	494	530	23
With An Allowance Recorded | Commercial Loans | Commercial and industrial
Financing Receivable, Impaired
Acquired Impaired Loans	28,829	5,748	1,590
Unpaid principal balance	28,329	5,746	1,482
Related allowance	(10,864)	(272)	(407)
Average recorded investment	29,333	5,975	1,849
Interest income recognized	1,107	313	24
With An Allowance Recorded | Commercial Loans | Energy-related
Financing Receivable, Impaired
Acquired Impaired Loans	53,967	13,046
Unpaid principal balance	53,088	13,020
Related allowance	(9,769)	(2,122)
Average recorded investment	47,469	13,899
Interest income recognized	1,677	454
With An Allowance Recorded | Residential Mortgage | Residential mortgage
Financing Receivable, Impaired
Acquired Impaired Loans	4,627	70
Unpaid principal balance	4,312	70
Related allowance	(144)	(1)
Average recorded investment	4,377	70
Interest income recognized	161	5
With An Allowance Recorded | Consumer and Other Loans | Consumer - Home equity
Financing Receivable, Impaired
Acquired Impaired Loans	13,906	3,859
Unpaid principal balance	13,257	3,683
Related allowance	(993)	(337)
Average recorded investment	10,227	2,453
Interest income recognized	434	73
With An Allowance Recorded | Consumer and Other Loans | Consumer - Indirect Automobile
Financing Receivable, Impaired
Acquired Impaired Loans	1,037
Unpaid principal balance	758
Related allowance	(114)
Average recorded investment	956
Interest income recognized	49
With An Allowance Recorded | Consumer and Other Loans | Consumer - Other
Financing Receivable, Impaired
Acquired Impaired Loans	2,447	130	17
Unpaid principal balance	2,442	129	17
Related allowance	(251)	(15)	(3)
Average recorded investment	1,469	30	18
Interest income recognized	$ 102	$ 3	$ 2

Loss Sharing Agreements and F76

Loss Sharing Agreements and FDIC Loss Share Receivable (Detail) $ in Millions	Dec. 20, 2016USD ($)	Dec. 31, 2010bank
Loss Sharing Agreements and FDIC Loss Share Receivable [Abstract]
Number of acquisitions | bank		6
Cash received upon termination of loss-share agreements	$ 6.5
Loss on termination of loss-share agreements	$ 17.8

Loss Sharing Agreements and F77

Loss Sharing Agreements and FDIC Loss Share Receivable - Schedule of FDIC Loss Share Receivables (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
FDIC Indemnification Asset
Balance at beginning of period	$ 39,878	$ 69,627
Reversal of loan loss provision recorded on FDIC covered loans	(1,497)	(1,360)	$ (4,260)
Amortization	(16,024)	(23,500)	(74,617)
Submission of reimbursable losses to the FDIC	(1,945)	(2,444)
Impairment	(20,402)	0
Changes due to a change in cash flow assumptions on OREO and other changes	(10)	(2,445)
Balance at end of period	$ 0	$ 39,878	$ 69,627

Transfers and Servicing of Fi78

Transfers and Servicing of Financial Assets (Including Mortgage Banking Activity) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Transfers and Servicing [Abstract]
Unpaid principal balances of loans serviced	$ 1,000,000	$ 888,400
Mortgage loans transferred to held for investment	$ (14,017)	$ 0	$ 0

Transfers and Servicing of Fi79

Transfers and Servicing of Financial Assets (including Mortgage Banking Activity) - Changes in Carrying Amount of Mortgage Loans Held-for-sale (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Loans Receivable Held-for-sale, Net, Reconciliation to Cash Flow [Roll Forward]
Balance at beginning of period	$ 166,247	$ 140,072	$ 128,442
Originations and purchases	2,460,033	2,464,588	1,675,538
Sales, net of gains	(2,451,459)	(2,432,979)	(1,657,409)
Mortgage loans transferred to held for investment	(14,017)	0	0
Other	(3,763)	(5,434)	(6,499)
Balance at end of period	$ 157,041	$ 166,247	$ 140,072

Transfers and Servicing of Fi80

Transfers and Servicing of Financial Assets (including Mortgage Banking Activity) - Components of Mortgage Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Participating Mortgage Loans
Gains on sales	$ 74,486	$ 83,957	$ 63,034
Total mortgage income	83,853	80,662	51,797
Mortgage income
Participating Mortgage Loans
Mortgage loans held for sale and derivatives	1,361	2,216	631
Derivative settlements, net	(6,640)	(5,017)	(8,743)
Gains on sales	87,925	82,671	59,156
Servicing and other income, net	1,207	792	753
Total mortgage income	$ 83,853	$ 80,662	$ 51,797

- Schedule of Mortgage Servicin

- Schedule of Mortgage Servicing Rights at Carrying Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	$ 75,412	$ 75,654
Accumulated Amortization	(53,251)	(45,134)
Net Carrying Amount	22,161	30,520
Mortgage servicing rights
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	7,202	6,104
Accumulated Amortization	(3,144)	(2,320)
Net Carrying Amount	$ 4,058	$ 3,784

Premises and Equipment - Schedu

Premises and Equipment - Schedule of Premises and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Land	$ 84,616	$ 84,438
Buildings	239,626	245,934
Furniture, fixtures and equipment	115,775	140,031
Total premises and equipment	440,017	470,403
Accumulated depreciation	(133,644)	(146,501)
Total premises and equipment, net	$ 306,373	$ 323,902

Premises and Equipment (Detail)

Premises and Equipment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment
Depreciation expense	$ 20.8	$ 22.2	$ 19.4
Maximum lease term	16 years
Average lease income (in usd per month)	$ 0.2
Total lease income	2.8	2.4	1.6
Rent expense	$ 16.6	15.4	$ 10.9
Minimum
Property, Plant and Equipment
Operating lease term (in years)	1 year
Maximum
Property, Plant and Equipment
Operating lease term (in years)	50 years
Buildings
Property, Plant and Equipment
Total allocated cost of portion of buildings held for lease	$ 8.7	8.2
Accumulated depreciation	$ 3.1	$ 2.6

Premises and Equipment - Sche84

Premises and Equipment - Schedule of Minimum Future Annual Rent Commitments (Detail) $ in Thousands	Dec. 31, 2016USD ($)
Property, Plant and Equipment [Abstract]
2,017	$ 15,927
2,018	14,981
2,019	13,980
2,020	12,742
2,021	10,906
2022 and thereafter	37,527
Total	$ 106,063

Goodwill and Other Acquired I85

Goodwill and Other Acquired Intangible Assets - Schedule of Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill
Balance at beginning of the period	$ 724,603	$ 517,526
Goodwill acquired during the year		207,077
Goodwill adjustments during the year	2,253
Balance at end of the period	726,856	724,603
Operating Segments | IBERIABANK
Goodwill
Balance at beginning of the period	696,260	489,183
Goodwill acquired during the year		207,077
Goodwill adjustments during the year	2,253
Balance at end of the period	698,513	696,260
Operating Segments | IMC
Goodwill
Balance at beginning of the period	23,178	23,178
Goodwill acquired during the year		0
Goodwill adjustments during the year	0
Balance at end of the period	23,178	23,178
Operating Segments | LTC
Goodwill
Balance at beginning of the period	5,165	5,165
Goodwill acquired during the year		0
Goodwill adjustments during the year	0
Balance at end of the period	$ 5,165	$ 5,165

Goodwill and Other Acquired I86

Goodwill and Other Acquired Intangible Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Title plant assets	$ 6.7	$ 6.7

Goodwill and Other Acquired I87

Goodwill and Other Acquired Intangible Assets - Schedule of Definite-Lived Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	$ 75,412	$ 75,654
Accumulated Amortization	(53,251)	(45,134)
Net Carrying Amount	22,161	30,520
Core deposit intangibles
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	74,001	74,001
Accumulated Amortization	(52,165)	(43,957)
Net Carrying Amount	21,836	30,044
Customer relationship intangible asset
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	1,348	1,348
Accumulated Amortization	(1,064)	(984)
Net Carrying Amount	284	364
Non-compete agreement
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	63	100
Accumulated Amortization	(22)	(79)
Net Carrying Amount	41	21
Other intangible assets
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	0	205
Accumulated Amortization	0	(114)
Net Carrying Amount	$ 0	$ 91

Goodwill and Other Acquired I88

Goodwill and Other Acquired Intangible Assets - Schedule of Amortization Expense of Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Aggregate amortization expense	$ 8,415	$ 7,811	$ 5,807
Estimated amortization expense for the years ended December 31:
2,017	6,733
2,018	5,740
2,019	5,019
2,020	3,513
2,021	1,066
2022 and thereafter	$ 90

Derivative Instruments and Ot89

Derivative Instruments and Other Hedging Activities - Schedule of Outstanding Derivative Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value of Derivatives
Derivative Asset	$ 38,886	$ 30,486
Derivative Liability	30,209	25,002
Notional Amount of Derivatives
Derivative assets	1,565,509	1,255,277
Derivative liabilities	1,528,184	993,274
Designated as Hedging Instruments
Fair Value of Derivatives
Derivative Asset	0	58
Derivative Liability	525	0
Notional Amount of Derivatives
Derivative assets	0	108,500
Derivative liabilities	108,500	0
Designated as Hedging Instruments | Interest rate contracts
Notional Amount of Derivatives
Derivative assets	0	108,500
Derivative liabilities	108,500	0
Designated as Hedging Instruments | Interest rate contracts | Other Assets
Fair Value of Derivatives
Derivative Asset	0	58
Designated as Hedging Instruments | Interest rate contracts | Other Liabilities
Fair Value of Derivatives
Derivative Liability	525	0
Not Designated as Hedging Instruments
Notional Amount of Derivatives
Derivative assets	1,565,509	1,146,777
Derivative liabilities	1,419,684	993,274
Not Designated as Hedging Instruments | Other Assets
Fair Value of Derivatives
Derivative Asset	38,886	30,428
Not Designated as Hedging Instruments | Other Liabilities
Fair Value of Derivatives
Derivative Liability	29,684	25,002
Not Designated as Hedging Instruments | Interest rate contracts
Notional Amount of Derivatives
Derivative assets	1,033,955	590,334
Derivative liabilities	1,033,955	590,334
Not Designated as Hedging Instruments | Interest rate contracts | Other Assets
Fair Value of Derivatives
Derivative Asset	20,719	18,077
Not Designated as Hedging Instruments | Interest rate contracts | Other Liabilities
Fair Value of Derivatives
Derivative Liability	20,719	18,077
Not Designated as Hedging Instruments | Foreign exchange contracts
Notional Amount of Derivatives
Derivative assets	4,474	4,392
Derivative liabilities	4,474	4,392
Not Designated as Hedging Instruments | Foreign exchange contracts | Other Assets
Fair Value of Derivatives
Derivative Asset	27	156
Not Designated as Hedging Instruments | Foreign exchange contracts | Other Liabilities
Fair Value of Derivatives
Derivative Liability	26	134
Not Designated as Hedging Instruments | Forward sales contracts
Notional Amount of Derivatives
Derivative assets	229,181	223,841
Derivative liabilities	120,567	173,430
Not Designated as Hedging Instruments | Forward sales contracts | Other Assets
Fair Value of Derivatives
Derivative Asset	6,014	1,588
Not Designated as Hedging Instruments | Forward sales contracts | Other Liabilities
Fair Value of Derivatives
Derivative Liability	794	474
Not Designated as Hedging Instruments | Written and purchased options
Notional Amount of Derivatives
Derivative assets	289,115	328,210
Derivative liabilities	154,170	181,949
Not Designated as Hedging Instruments | Written and purchased options | Other Assets
Fair Value of Derivatives
Derivative Asset	12,125	10,607
Not Designated as Hedging Instruments | Written and purchased options | Other Liabilities
Fair Value of Derivatives
Derivative Liability	8,098	6,254
Not Designated as Hedging Instruments | Other contracts
Notional Amount of Derivatives
Derivative assets	8,784	0
Derivative liabilities	106,518	43,169
Not Designated as Hedging Instruments | Other contracts | Other Assets
Fair Value of Derivatives
Derivative Asset	1	0
Not Designated as Hedging Instruments | Other contracts | Other Liabilities
Fair Value of Derivatives
Derivative Liability	$ 47	$ 63

Derivative Instruments and Ot90

Derivative Instruments and Other Hedging Activities (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Notional amount of derivative liabilities	$ 1,528,184,000	$ 993,274,000
Cash as collateral for derivative transactions	1,900,000	10,900,000
Not Designated as Hedging Instruments
Derivative [Line Items]
Notional amount of derivative liabilities	1,419,684,000	993,274,000
Not Designated as Hedging Instruments | Other contracts
Derivative [Line Items]
Notional amount of derivative liabilities	$ 106,518,000	43,169,000
Exposure if third parties default		$ 0

Derivative Instruments and Ot91

Derivative Instruments and Other Hedging Activities - Reconciliation of Gross Amounts in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivative assets
Gross derivative assets	$ 28,804	$ 24,596
Gross amounts not offset in the Balance Sheet, derivatives	(9,677)	(162)
Gross amounts not offset in the Balance Sheet, collateral	0	0
Net derivative assets	19,127	24,434
Derivative liabilities
Gross derivative liabilities	21,244	18,284
Gross amounts not offset in the Balance Sheet, derivatives	(9,677)	(162)
Gross amounts not offset in the Balance Sheet, collateral	(1,892)	(10,877)
Net derivative liabilities	9,675	7,245
Written and purchased options
Derivative assets
Gross derivative assets	8,085	6,255
Gross amounts not offset in the Balance Sheet, derivatives	0	0
Gross amounts not offset in the Balance Sheet, collateral	0	0
Net derivative assets	8,085	6,255
Designated as Hedging Instruments | Interest rate contracts
Derivative assets
Gross derivative assets	20,719	100
Gross amounts not offset in the Balance Sheet, derivatives	(9,677)	(43)
Gross amounts not offset in the Balance Sheet, collateral	0	0
Net derivative assets	11,042	57
Derivative liabilities
Gross derivative liabilities	525	43
Gross amounts not offset in the Balance Sheet, derivatives	0	(43)
Gross amounts not offset in the Balance Sheet, collateral	(181)	0
Net derivative liabilities	344	0
Not Designated as Hedging Instruments | Interest rate contracts
Derivative assets
Gross derivative assets		18,241
Gross amounts not offset in the Balance Sheet, derivatives		(119)
Gross amounts not offset in the Balance Sheet, collateral		0
Net derivative assets		18,122
Derivative liabilities
Gross derivative liabilities	20,719	18,241
Gross amounts not offset in the Balance Sheet, derivatives	(9,677)	(119)
Gross amounts not offset in the Balance Sheet, collateral	(1,711)	(10,877)
Net derivative liabilities	$ 9,331	$ 7,245

Derivative Instruments and Ot92

Derivative Instruments and Other Hedging Activities - Effect of Hedging Instruments on Consolidated Financial Statements (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Designated as Hedging Instruments | Cash Flow Hedging | Interest rate contracts | Interest expense
Derivative Instruments and Hedging Activities Disclosures
Amount of Gain (Loss) Recognized in OCI net of taxes (Effective Portion)	$ (428)	$ 38	$ 0
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income net of taxes (Effective Portion)	50	0	0
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0	0	(1)
Not Designated as Hedging Instruments
Derivative Instruments and Hedging Activities Disclosures
Amount of Gain (Loss) Recognized in Income on Derivatives	6,804	1,492	(6,451)
Not Designated as Hedging Instruments | Interest rate contracts | Other income
Derivative Instruments and Hedging Activities Disclosures
Amount of Gain (Loss) Recognized in Income on Derivatives	8,830	4,143	2,513
Not Designated as Hedging Instruments | Foreign exchange contracts | Other income
Derivative Instruments and Hedging Activities Disclosures
Amount of Gain (Loss) Recognized in Income on Derivatives	15	22	0
Not Designated as Hedging Instruments | Forward sales contracts | Mortgage income
Derivative Instruments and Hedging Activities Disclosures
Amount of Gain (Loss) Recognized in Income on Derivatives	(1,731)	(2,947)	(3,225)
Not Designated as Hedging Instruments | Written and purchased options | Mortgage income
Derivative Instruments and Hedging Activities Disclosures
Amount of Gain (Loss) Recognized in Income on Derivatives	(327)	274	(5,739)
Not Designated as Hedging Instruments | Other contracts | Other income
Derivative Instruments and Hedging Activities Disclosures
Amount of Gain (Loss) Recognized in Income on Derivatives	$ 17	$ 0	$ 0

Derivative Instruments and Ot93

Derivative Instruments and Other Hedging Activities - Outstanding Interest Rate Swap Agreements Not Designated as Hedging Instruments (Detail) - Not Designated as Hedging Instruments - Interest Rate Swap - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Weighted average pay rate	4.10%	3.20%	2.90%
Weighted average receive rate	2.50%	0.90%	0.40%
Weighted average maturity in years	7 years 4 months 24 days	7 years 6 months	7 years 8 months 12 days
Unrealized gain (loss) relating to interest rate swaps	$ 0	$ 0	$ 0

Deposits - Schedule of Deposits

Deposits - Schedule of Deposits by Type (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Banking and Thrift [Abstract]
Non-interest-bearing deposits	$ 4,928,878	$ 4,352,229
Negotiable order of withdrawal (NOW)	3,314,281	2,974,176
Money market deposits accounts (MMDA)	6,219,532	6,010,882
Savings deposits	814,385	716,838
Certificates of deposit and other time deposits	2,131,207	2,124,623
Total deposits	$ 17,408,283	$ 16,178,748	$ 12,520,525

Deposits - Schedule of Time Dep

Deposits - Schedule of Time Deposits (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Banking and Thrift [Abstract]
Time Deposits, Less than $250,000	$ 1,661,631	$ 1,456,804
Time Deposits, $250,000 or More	469,576	667,819
Total time deposits	$ 2,131,207	$ 2,124,623

Deposits - Schedule of Maturiti

Deposits - Schedule of Maturities of Certificates of Deposit (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Banking and Thrift [Abstract]
2,017	$ 1,335,041
2,018	507,162
2,019	96,509
2,020	83,623
2,021	60,468
2022 and thereafter	48,404
Total time deposits	$ 2,131,207	$ 2,124,623

Short-Term Borrowings - Summary

Short-Term Borrowings - Summary of Short-Term Borrowings (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Federal Home Loan Bank advances	$ 175,000	$ 110,000
Securities sold under agreements to repurchase	334,136	216,617
Total short-term borrowings	509,136	326,617	$ 845,742
Short-term Debt, Other Disclosures
Outstanding at December 31	509,136	326,617	845,742
Maximum month-end outstanding balance	807,993	798,933	1,034,741
Average daily outstanding balance	$ 614,073	$ 426,011	$ 782,033
Average rate during the year	0.39%	0.18%	0.17%
Average rate at year end	0.30%	0.20%	0.18%

Long-Term Debt - Schedule of Lo

Long-Term Debt - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument
Long-term debt	$ 628,953	$ 340,447
IBERIABANK
Debt Instrument
Long-term debt	508,843	220,337
IBERIABANK | Federal Home Loan Bank Notes
Debt Instrument
Long-term debt	$ 480,118	$ 136,628
IBERIABANK | Federal Home Loan Bank Notes | Minimum
Debt Instrument
Interest rate	0.864%	0.903%
IBERIABANK | Federal Home Loan Bank Notes | Maximum
Debt Instrument
Interest rate	7.04%	7.04%
IBERIABANK | Notes Payable
Debt Instrument
Long-term debt	$ 28,725	$ 83,709
IBERIABANK | Notes Payable | Minimum
Debt Instrument
Interest rate	0.50%	0.50%
Debt Instrument term	7 years	7 years
IBERIABANK | Notes Payable | Maximum
Debt Instrument
Interest rate	3.00%	5.00%
Debt Instrument term	40 years	40 years
IBERIABANK Corporation | Junior Subordinated Debt
Debt Instrument
Long-term debt	$ 120,110	$ 120,110
Debt Instrument term	30 years
IBERIABANK Corporation | Junior Subordinated Debt | Statutory Trust I, 3 month LIBOR, plus 3.25%
Debt Instrument
Long-term debt	$ 10,310	10,310
IBERIABANK Corporation | Junior Subordinated Debt | Statutory Trust II, 3 month LIBOR, plus 3.15%
Debt Instrument
Long-term debt	10,310	10,310
IBERIABANK Corporation | Junior Subordinated Debt | Statutory Trust III, 3 month LIBOR, plus 2.00%
Debt Instrument
Long-term debt	10,310	10,310
IBERIABANK Corporation | Junior Subordinated Debt | Statutory Trust IV, 3 month LIBOR, plus 1.60%
Debt Instrument
Long-term debt	15,464	15,464
IBERIABANK Corporation | Junior Subordinated Debt | American Horizons Statutory Trust I, 3 month LIBOR, plus 3.15%
Debt Instrument
Long-term debt	6,186	6,186
IBERIABANK Corporation | Junior Subordinated Debt | Statutory Trust V, 3 month LIBOR, plus 1.435%
Debt Instrument
Long-term debt	10,310	10,310
IBERIABANK Corporation | Junior Subordinated Debt | Statutory Trust VI, 3 month LIBOR, plus 2.75%
Debt Instrument
Long-term debt	12,372	12,372
IBERIABANK Corporation | Junior Subordinated Debt | Statutory Trust VII, 3 month LIBOR, plus 2.54%
Debt Instrument
Long-term debt	13,403	13,403
IBERIABANK Corporation | Junior Subordinated Debt | Statutory Trust VIII, 3 month LIBOR, plus 3.50%
Debt Instrument
Long-term debt	7,217	7,217
IBERIABANK Corporation | Junior Subordinated Debt | OMNI Trust I, 3 month LIBOR, plus 3.30%
Debt Instrument
Long-term debt	8,248	8,248
IBERIABANK Corporation | Junior Subordinated Debt | OMNI Trust II, 3 Month LIBOR, plus 2.79%
Debt Instrument
Long-term debt	7,732	7,732
IBERIABANK Corporation | Junior Subordinated Debt | GA Commerce Trust II, 3 Month LIBOR, plus 1.64%
Debt Instrument
Long-term debt	$ 8,248	$ 8,248
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate
Debt Instrument
Three month LIBOR rate during period	1.00%	0.61%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | Statutory Trust I, 3 month LIBOR, plus 3.25%
Debt Instrument
Basis spread on variable rate	3.25%	3.25%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | Statutory Trust II, 3 month LIBOR, plus 3.15%
Debt Instrument
Basis spread on variable rate	3.15%	3.15%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | Statutory Trust III, 3 month LIBOR, plus 2.00%
Debt Instrument
Basis spread on variable rate	2.00%	2.00%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | Statutory Trust IV, 3 month LIBOR, plus 1.60%
Debt Instrument
Basis spread on variable rate	1.60%	1.60%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | American Horizons Statutory Trust I, 3 month LIBOR, plus 3.15%
Debt Instrument
Basis spread on variable rate	3.15%	3.15%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | Statutory Trust V, 3 month LIBOR, plus 1.435%
Debt Instrument
Basis spread on variable rate	1.435%	1.435%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | Statutory Trust VI, 3 month LIBOR, plus 2.75%
Debt Instrument
Basis spread on variable rate	2.75%	2.75%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | Statutory Trust VII, 3 month LIBOR, plus 2.54%
Debt Instrument
Basis spread on variable rate	2.54%	2.54%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | Statutory Trust VIII, 3 month LIBOR, plus 3.50%
Debt Instrument
Basis spread on variable rate	3.50%	3.50%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | OMNI Trust I, 3 month LIBOR, plus 3.30%
Debt Instrument
Basis spread on variable rate	3.30%	3.30%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | OMNI Trust II, 3 Month LIBOR, plus 2.79%
Debt Instrument
Basis spread on variable rate	2.79%	2.79%
IBERIABANK Corporation | Junior Subordinated Debt | 3 Month LIBOR Rate | GA Commerce Trust II, 3 Month LIBOR, plus 1.64%
Debt Instrument
Basis spread on variable rate	1.64%	1.64%

Long-Term Debt (Detail)

Long-Term Debt (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument
Long-term debt	$ 628,953	$ 340,447
IBERIABANK
Debt Instrument
Long-term debt	$ 508,843	220,337
IBERIABANK | Federal Home Loan Bank Notes
Debt Instrument
Minimum FHLB advance amortization period	1 year 6 months
Maximum FHLB advance amortization period	30 years
Long-term debt	$ 480,118	136,628
IBERIABANK | Federal Home Loan Bank Notes | Blanket Floating Lien
Debt Instrument
Additional advances available from FHLB	4,900,000
IBERIABANK | Federal Home Loan Bank Notes | Pledge of Investment Securities
Debt Instrument
Additional advances available from FHLB	1,500,000
IBERIABANK Corporation | Junior Subordinated Debt
Debt Instrument
Long-term debt	$ 120,110	$ 120,110
Debt Instrument term	30 years
Earliest call date after issue	5 years
Earliest interest payment deferral date (in years or 20 consecutive quarters)	5 years
Percent of subordinate debt excluded from Tier 1 regulatory capital requirements	100.00%	75.00%
Increase in percent of subordinate debt excluded from Tier 1 regulatory capital requirements	25.00%
Weighted Average | IBERIABANK | Federal Home Loan Bank Notes
Debt Instrument
Weighted average advance rate on FHLB advances	1.76%	3.79%

Long-Term Debt - Maturities of

Long-Term Debt - Maturities of Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Disclosure [Abstract]
2,017	$ 55,516
2,018	233,667
2,019	97,042
2,020	15,263
2,021	55,564
2022 and thereafter	171,901
Total long-term debt	$ 628,953	$ 340,447

- Schedule of Provision for Inc

- Schedule of Provision for Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Current expense	$ 103,335	$ 67,025	$ 69,612
Deferred expense (benefit)	(16,654)	4,551	(25,027)
Tax credits	(7,112)	(11,268)	(12,012)
Amortization on qualified affordable housing tax credits	4,185	2,023	1,005
Tax benefits attributable to items charged to equity and goodwill	1,439	1,763	2,105
Total income tax expense	$ 85,193	$ 64,094	$ 35,683

Income Taxes (Detail)

Income Taxes (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Taxes payable	$ 2,000,000
Tax receivable, federal and state income taxes		$ 13,000,000
Federal statutory income tax rate	35.00%
Net tax benefit from other items	$ 6,886,000	2,024,000	$ 792,000
Decrease related to prior year taxes	6,500,000
Other discrete items	200,000
Business Acquisition
Basis difference in acquired assets	$ 32,923,000	48,256,000
Expiration period for net operating loss carryforwards (in years)	20 years
Valuation allowance	$ 0	0
Retained earnings of prior period	21,900,000	$ 21,900,000
Florida Bank Group, Inc.
Business Acquisition
Basis difference in acquired assets	$ 6,500,000

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Effective Tax Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Federal tax based on statutory rate	$ 95,189	$ 72,428	$ 49,373
Effect of tax-exempt income	(8,203)	(6,919)	(7,064)
Interest and other nondeductible expenses	3,250	5,899	2,642
State taxes, net of federal benefit	4,770	3,955	2,531
Tax credits	(7,112)	(11,268)	(12,012)
Amortization on qualified affordable housing tax credits	4,185	2,023	1,005
Other	(6,886)	(2,024)	(792)
Total income tax expense	$ 85,193	$ 64,094	$ 35,683
Effective tax rate	31.30%	31.00%	25.30%

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax asset:
NOL carryforward	$ 19,584	$ 17,258
Allowance for credit losses	58,036	56,446
Deferred compensation	10,852	7,528
Basis difference in acquired assets	32,923	48,256
Unrealized loss on securities available for sale	14,019	854
OREO	4,498	6,210
Other	14,754	10,438
Deferred tax assets	154,666	146,990
Deferred tax liability:
Basis difference in acquired assets	(13,150)	(31,975)
Gain on acquisition	0	(212)
FHLB stock	(270)	(122)
Premises and equipment	(6,132)	(1,658)
Acquisition intangibles	(8,134)	(7,648)
Deferred loan costs	(4,702)	(4,610)
Investments acquired	0	(167)
Other	(9,196)	(16,694)
Deferred tax liabilities	(41,584)	(63,086)
Net deferred tax asset	$ 113,082	$ 83,904

Shareholders' Equity, Capita105

Shareholders' Equity, Capital Ratios and Other Regulatory Matters - Shareholders' Equity (Details)	Dec. 07, 2016USD ($)$ / sharesshares	May 09, 2016USD ($)$ / sharesshares	Aug. 05, 2015USD ($)$ / sharesshares	Jun. 30, 2016$ / sharesshares	Dec. 31, 2016USD ($)$ / shares	Dec. 31, 2015USD ($)$ / shares	Dec. 31, 2014USD ($)
Class of Stock [Line Items]
Proceeds from common stock issued | $					$ 279,242,000	$ 0	$ 0
Preferred stock, par value (in usd per share)					$ 1	$ 1
Liquidation preference (per share)					$ 10,000	$ 10,000
Liquidation preference value | $		$ 137,500,000
Carrying Amount | $					$ 132,097,000	$ 76,812,000
Number of shares authorized to be repurchased | shares				950,000
Common stock repurchases (in shares) | shares				(202,506)
Average price per share of common stock repurchased				$ 57.61
Series B Depositary Shares
Class of Stock [Line Items]
Common stock issued (in shares) | shares			3,200,000
Depository shares to preferred stock ratio			0.0025
Liquidation preference per depositary share			25
Series B Preferred Stock
Class of Stock [Line Items]
Ownership per share			6.625%
Preferred stock, par value (in usd per share)			$ 1
Liquidation preference (per share)			$ 10,000
Liquidation preference value | $			$ 80,000,000
Carrying Amount | $					76,812,000	76,812,000
Series C Depository Shares
Class of Stock [Line Items]
Common stock issued (in shares) | shares		2,300,000
Depository shares to preferred stock ratio		0.0025
Liquidation preference per depositary share		25
Series C Preferred Stock
Class of Stock [Line Items]
Ownership per share		6.60%
Preferred stock, par value (in usd per share)		$ 1
Liquidation preference (per share)		$ 10,000
Liquidation preference value | $		$ 57,500,000
Carrying Amount | $					$ 55,285,000	$ 0
Common Stock
Class of Stock [Line Items]
Common stock issued (in shares) | shares	3,593,750
Price per share of stock of issued	$ 81.50
Proceeds from common stock issued | $	$ 279,200,000
3 Month LIBOR Rate | Series B Preferred Stock
Class of Stock [Line Items]
Variable dividend rate			4.262%
3 Month LIBOR Rate | Series C Preferred Stock
Class of Stock [Line Items]
Variable dividend rate		4.92%

Shareholders' Equity, Capita106

Shareholders' Equity, Capital Ratios and Other Regulatory Matters - Actual Capital Amounts and Ratios (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Consolidated
Tier 1 Leverage
Minimum amount	$ 818,440	$ 751,798
Minimum ratio	4.00%	4.00%
Actual amount	$ 2,221,528	$ 1,790,034
Actual ratio	10.86%	9.52%
Common Equity Tier 1 (CET1)
Minimum amount	$ 794,334	$ 750,616
Minimum ratio	4.50%	4.50%
Actual amount	$ 2,089,431	$ 1,684,097
Actual ratio	11.84%	10.10%
Tier 1 Risk-Based Capital (1)
Minimum amount	$ 1,059,112	$ 1,000,822
Minimum ratio	6.00%	6.00%
Actual amount	$ 2,221,528	$ 1,790,034
Actual ratio	12.59%	10.73%
Total Risk-Based Capital (1)
Minimum amount	$ 1,412,149	$ 1,334,429
Minimum ratio	8.00%	8.00%
Actual amount	$ 2,493,988	$ 2,029,932
Actual ratio	14.13%	12.17%
IBERIABANK
Tier 1 Leverage
Minimum amount	$ 816,152	$ 749,226
Minimum ratio	4.00%	4.00%
Well capitalized amount	$ 1,020,190	$ 936,532
Well capitalized ratio	5.00%	5.00%
Actual amount	$ 1,878,703	$ 1,691,022
Actual ratio	9.21%	9.03%
Common Equity Tier 1 (CET1)
Minimum amount	$ 792,111	$ 748,667
Minimum ratio	4.50%	4.50%
Well capitalized amount	$ 1,144,160	$ 1,081,408
Well capitalized ratio	6.50%	6.50%
Actual amount	$ 1,878,703	$ 1,691,022
Actual ratio	10.67%	10.16%
Tier 1 Risk-Based Capital (1)
Minimum amount	$ 1,056,147	$ 998,223
Minimum ratio	6.00%	6.00%
Well capitalized amount	$ 1,408,197	$ 1,330,964
Well capitalized ratio	8.00%	8.00%
Actual amount	$ 1,878,703	$ 1,691,022
Actual ratio	10.67%	10.16%
Total Risk-Based Capital (1)
Minimum amount	$ 1,408,197	$ 1,330,964
Minimum ratio	8.00%	8.00%
Well capitalized amount	$ 1,760,246	$ 1,663,705
Well capitalized ratio	10.00%	10.00%
Actual amount	$ 2,034,663	$ 1,843,545
Actual ratio	11.56%	11.08%
Dividend payable restriction	$ 191,000
Funds available for loans or advances to the parent	$ 187,900

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Calculation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings per common share - basic
Net income	$ 186,777	$ 142,844	$ 105,382
Preferred stock dividends	(7,977)	0	0
Dividends and undistributed earnings allocated to unvested restricted shares	(1,872)	(1,680)	(1,651)
Net income allocated to common shareholders - basic	$ 176,928	$ 141,164	$ 103,731
Weighted average common shares outstanding	40,948	38,214	31,307
Earnings per common share - basic (in usd per share)	$ 4.32	$ 3.69	$ 3.31
Earnings per common share - diluted
Net income allocated to common shareholders - basic	$ 176,928	$ 141,164	$ 103,731
Dividends and undistributed earnings allocated to unvested restricted shares	(37)	(48)	(34)
Earnings Allocated to Common Shareholders	$ 176,891	$ 141,116	$ 103,697
Weighted average common shares outstanding	40,948	38,214	31,307
Dilutive potential common shares	158	96	126
Weighted average common shares outstanding - diluted	41,106	38,310	31,433
Earnings per common share - diluted (in usd per share)	$ 4.30	$ 3.68	$ 3.30

Earnings Per Share (Detail)

Earnings Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share
Weighted average number of shares held by Recognition and Retention Plan excluded from the calculation for basic shares outstanding	447,818	607,608	625,555
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share
Antidilutive securities excluded from the computation of earnings per share	155,969	159,236	13,101

Share-Based Compensation (Detai

Share-Based Compensation (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Future awards shares under approved incentive compensation plans	2,456,052
Share-based compensation maximum option term (in years)	10 years
Contributions made by the company to 401(k) plan	$ 1.9	$ 1.7	$ 1.5
Stock Option Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned share-based compensation associated with awards	$ 2.1
Unrecognized compensation cost related to stock options expected to be recognized over a weighted-average period	2 years 7 months 6 days
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned share-based compensation associated with awards	$ 16	$ 19.5
Unrecognized compensation cost related to stock options expected to be recognized over a weighted-average period	2 years 2 months 12 days
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Phantom Stock Awards | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	5 years
Phantom Stock Awards | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	7 years

Share-Based Compensation - Acti

Share-Based Compensation - Activity Related to Stock Options (Detail) - Stock Option Awards - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number of shares
Balance at beginning of the period (in shares)	813,777	867,682	1,072,829
Granted (in shares)	160,624	82,001	77,434
Exercised (in shares)	(196,769)	(119,917)	(267,421)
Forfeited or expired (in shares)	(56,094)	(15,989)	(15,160)
Balance at end of the period (in shares)	721,538	813,777	867,682
Exercisable at period end (in shares)	415,376	546,842	562,752
Weighted Average Exercise Price
Balance at beginning of the period (in usd per share)	$ 56.99	$ 55.92	$ 53.47
Granted (in usd per share)	48.65	62.50	65.31
Exercised (in usd per share)	55.39	51.71	48.57
Forfeited or expired (in usd per share)	59.49	66.52	60.38
Balance at end of the period (in usd per share)	55.38	56.99	55.92
Exercisable at period end (in usd per share)	$ 56.66	$ 56.54	$ 55.92
Aggregate Intrinsic Value (Dollars in thousands)
Exercised	$ 3,597	$ 1,516	$ 4,612
Balance at end of period	20,583
Exercisable at period end	$ 11,366
Weighted Average Remaining Contract Life (in years)
Weighted average remaining contract life at period end	6 years
Exercisable at period end	4 years 4 months 24 days

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of Weighted Average Remaining Life of Options Outstanding within Stated Exercise Prices (Detail) - Stock Option Awards	12 Months Ended
	Dec. 31, 2016$ / sharesshares
Options Outstanding
Number of options (in shares) | shares	721,538
Weighted average exercise price (in usd per share)	$ 55.38
Weighted average remaining contract life	6 years
Options Exercisable
Number of Options (in shares) | shares	415,376
Weighted average exercise price (in usd per share)	$ 56.66
$36.48 to $47.50
Options Outstanding
Number of options (in shares) | shares	147,913
Weighted average exercise price (in usd per share)	$ 47.27
Weighted average remaining contract life	8 years 10 months 24 days
Options Exercisable
Number of Options (in shares) | shares	5,849
Weighted average exercise price (in usd per share)	$ 45.42
Minimum exercise price (in usd per share)	36.48
Maximum exercise price (in usd per share)	$ 47.50
$47.51 to $52.35
Options Outstanding
Number of options (in shares) | shares	151,527
Weighted average exercise price (in usd per share)	$ 51.56
Weighted average remaining contract life	4 years 10 months 24 days
Options Exercisable
Number of Options (in shares) | shares	113,328
Weighted average exercise price (in usd per share)	$ 51.51
Minimum exercise price (in usd per share)	47.51
Maximum exercise price (in usd per share)	$ 52.35
$52.36 to $54.82
Options Outstanding
Number of options (in shares) | shares	116,558
Weighted average exercise price (in usd per share)	$ 53.39
Weighted average remaining contract life	4 years 7 months 6 days
Options Exercisable
Number of Options (in shares) | shares	90,653
Weighted average exercise price (in usd per share)	$ 53.68
Minimum exercise price (in usd per share)	52.36
Maximum exercise price (in usd per share)	$ 54.82
$54.83 to $59.81
Options Outstanding
Number of options (in shares) | shares	68,683
Weighted average exercise price (in usd per share)	$ 56.33
Weighted average remaining contract life	3 years 8 months 12 days
Options Exercisable
Number of Options (in shares) | shares	64,387
Weighted average exercise price (in usd per share)	$ 56.17
Minimum exercise price (in usd per share)	54.83
Maximum exercise price (in usd per share)	$ 59.81
$59.82 to $62.82
Options Outstanding
Number of options (in shares) | shares	154,506
Weighted average exercise price (in usd per share)	$ 61.32
Weighted average remaining contract life	5 years 8 months 12 days
Options Exercisable
Number of Options (in shares) | shares	98,688
Weighted average exercise price (in usd per share)	$ 60.63
Minimum exercise price (in usd per share)	59.82
Maximum exercise price (in usd per share)	$ 62.82
$62.83 to $111.71
Options Outstanding
Number of options (in shares) | shares	82,351
Weighted average exercise price (in usd per share)	$ 67.83
Weighted average remaining contract life	7 years 1 month 6 days
Options Exercisable
Number of Options (in shares) | shares	42,471
Weighted average exercise price (in usd per share)	$ 69.81
Minimum exercise price (in usd per share)	62.83
Maximum exercise price (in usd per share)	$ 111.71

Share-Based Compensation - Esti

Share-Based Compensation - Estimate Fair Value of Stock Option Awards with Weighted-Average Assumptions (Detail) - Stock Option Awards - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividends	2.80%	2.20%	2.10%
Expected volatility	29.00%	35.60%	35.80%
Risk-free interest rate	1.40%	2.00%	2.30%
Expected term (in years)	6 years 6 months	7 years 6 months	7 years 6 months
Weighted-average grant-date fair value	$ 10.46	$ 19.57	$ 21.26

Share-Based Compensation - Comp

Share-Based Compensation - Compensation Expense Included in Non-Interest Expense and Related Income Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock Option Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 2,010	$ 1,861	$ 2,053
Income tax benefit	331	317	375
Restricted Stock And Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	12,513	12,045	9,932
Income tax benefit	4,380	4,215	3,476
Phantom Stock and Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 12,933	$ 12,109	$ 5,496

Share-Based Compensation - Unve

Share-Based Compensation - Unvested Restricted Stock Award Activity (Detail) - Restricted Stock And Restricted Stock Units - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at beginning of the period (in shares)	507,130	506,289	523,756
Granted (in shares)	254,276	207,575	168,254
Forfeited (in shares)	(28,855)	(26,970)	(18,171)
Earned and issued (in shares)	(189,290)	(179,764)	(167,550)
Balance at end of the period (in shares)	543,261	507,130	506,289
Weighted average grant date fair value (in usd per share)	$ 48.84	$ 63.16	$ 65.11
Fair value of restricted stock and restricted share units vested during the period	$ 10.7	$ 11.3	$ 10.9

Share-Based Compensation - S115

Share-Based Compensation - Schedule of Share and Dividend Equivalent Share Award Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Value of share equivalents
Market price of Company's stock	$ 83.75	$ 55.07	$ 64.85
Phantom Stock and Performance Stock Units
Number of share equivalents
Balance at beginning of the period (in shares)	462,430	475,347	433,884
Granted (in shares)	215,745	167,573	146,166
Forfeited share equivalents (in shares)	(42,051)	(34,681)	(22,800)
Vested share equivalents (in shares)	(163,294)	(145,809)	(81,903)
Balance at end of the period (in shares)	472,830	462,430	475,347
Value of share equivalents
Balance at beginning of the period (in shares)	$ 25,466	$ 30,826	$ 27,270
Granted (in shares)	18,069	9,228	9,479
Forfeited share equivalents (in shares)	(3,522)	(1,910)	(1,479)
Vested share equivalents (in shares)	(8,509)	(9,288)	(5,512)
Balance at end of the period (in shares)	$ 39,600	$ 25,466	$ 30,826

Commitments and Contingencie116

Commitments and Contingencies (Detail) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Fair value of guarantees under commercial and standby letters of credit	$ 1.6	$ 1.5

Commitments and Contingencies -

Commitments and Contingencies - Summary of Financial Instruments Outstanding (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]
Commitments to grant loans	$ 355,558	$ 61,240
Unfunded commitments under lines of credit	4,899,930	4,617,802
Commercial and standby letters of credit	163,560	150,281
Reserve for unfunded lending commitments	$ 11,241	$ 14,145	$ 11,801	$ 11,147

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Assets
Securities available for sale, at fair value	$ 3,446,097,000	$ 2,800,286,000
Mortgage loans held for sale	157,041,000	166,247,000
Derivative instruments	28,804,000	24,596,000
Liabilities
Derivative instruments	21,244,000	18,284,000
Fair value assets transferred from Level 1 to Level 2	0	0
Recurring
Assets
Securities available for sale, at fair value	3,446,097,000	2,800,286,000
Mortgage loans held for sale	157,041,000	166,247,000
Derivative instruments	38,886,000	30,486,000
Total, Assets	3,642,024,000	2,997,019,000
Liabilities
Derivative instruments	30,209,000	25,002,000
Total	30,209,000	25,002,000
Recurring | Level 1
Assets
Securities available for sale, at fair value	0	0
Mortgage loans held for sale	0	0
Derivative instruments	0	0
Total, Assets	0	0
Liabilities
Derivative instruments	0	0
Total	0	0
Recurring | Level 2
Assets
Securities available for sale, at fair value	3,446,097,000	2,800,286,000
Mortgage loans held for sale	157,041,000	166,247,000
Derivative instruments	38,886,000	30,486,000
Total, Assets	3,642,024,000	2,997,019,000
Liabilities
Derivative instruments	30,209,000	25,002,000
Total	30,209,000	25,002,000
Recurring | Level 3
Assets
Securities available for sale, at fair value	0	0
Mortgage loans held for sale	0	0
Derivative instruments	0	0
Total, Assets	0	0
Liabilities
Derivative instruments	0	0
Total	$ 0	$ 0

Fair Value Measurements - Gains

Fair Value Measurements - Gains and Losses Included in Earnings Related to Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Non-interest Income
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation
Total gains (losses) included in earnings	$ 5,567
Change in unrealized gains (losses) relating to assets still held at December 31, 2016	0
Other Comprehensive Income (loss) net of tax
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation
Total gains (losses) included in earnings	0
Change in unrealized gains (losses) relating to assets still held at December 31, 2016	$ (24,450)

Fair Value Measurements - Fi120

Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Nonrecurring Basis (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets
Unpaid principal balance	$ 292,645,000	$ 66,641,000	$ 11,700,000
Related allowance	22,776,000	3,993,000	430,000
Nonrecurring
Assets
Loans	93,485,000	31,669,000
OREO, net	185,000	1,662,000
Total	93,670,000	33,331,000
Fair value of liabilities	0	0	$ 0
Nonrecurring | Level 1
Assets
Loans	0	0
OREO, net	0	0
Total	0	0
Nonrecurring | Level 2
Assets
Loans	0	0
OREO, net	0	0
Total	0	0
Nonrecurring | Level 3
Assets
Loans	93,485,000	31,669,000
OREO, net	185,000	1,662,000
Total	93,670,000	33,331,000
Fair Value
Assets
Unpaid principal balance	125,500,000	40,200,000
Related allowance	$ 32,000,000	$ 8,500,000

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Difference Between the Aggregate Fair Value and the Aggregate Unpaid Principal Balance for Mortgage Loans Held for Sale (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Loans held fro investment at fair value	$ 12,700
Mortgages Held For Sale at Fair Value
Aggregate fair value	157,041	$ 166,247
Aggregate unpaid principal	153,801	161,083
Aggregate fair value less unpaid principal	3,240	5,164
Total mortgage income (loss) in the Consolidated Statement of Comprehensive Income	$ 2,100	$ 1,000

Fair Value of Financial Inst122

Fair Value of Financial Instruments - Estimated Fair Values and Carrying Amounts of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financial Assets
Cash and cash equivalents	$ 1,362,126	$ 510,267	$ 548,095	$ 391,396
Loans and loans held for sale, net of unearned income and allowance for loan losses	15,222,012	14,493,675	11,581,116
FDIC loss share receivables	0	39,878	69,627
Derivative instruments	38,886	30,486
Financial Liabilities
Deposits	17,408,283	16,178,748	12,520,525
Short-term borrowings	509,136	326,617	$ 845,742
Long-term debt	628,953	340,447
Derivative instruments	30,209	25,002
Level 1
Financial Assets
Cash and cash equivalents	1,362,126	510,267
Investment securities	0	0
Loans and loans held for sale, net of unearned income and allowance for loan losses	0	0
FDIC loss share receivables	0	0
Derivative instruments	0	0
Financial Liabilities
Deposits	0	0
Short-term borrowings	334,136	216,617
Long-term debt	0	0
Derivative instruments	0	0
Level 2
Financial Assets
Cash and cash equivalents	0	0
Investment securities	3,536,029	2,901,247
Loans and loans held for sale, net of unearned income and allowance for loan losses	157,041	166,247
FDIC loss share receivables	0	0
Derivative instruments	38,886	30,486
Financial Liabilities
Deposits	0	0
Short-term borrowings	175,000	110,000
Long-term debt	0	0
Derivative instruments	30,209	25,002
Level 3
Financial Assets
Cash and cash equivalents	0	0
Investment securities	0	0
Loans and loans held for sale, net of unearned income and allowance for loan losses	14,909,014	14,508,502
FDIC loss share receivables	0	9,163
Derivative instruments	0	0
Financial Liabilities
Deposits	16,762,475	15,696,245
Short-term borrowings	0	0
Long-term debt	617,656	309,847
Derivative instruments	0	0
Carrying Amount
Financial Assets
Cash and cash equivalents	1,362,126	510,267
Investment securities	3,535,313	2,899,214
Loans and loans held for sale, net of unearned income and allowance for loan losses	15,077,293	14,355,297
FDIC loss share receivables	0	39,878
Derivative instruments	38,886	30,486
Financial Liabilities
Deposits	17,408,283	16,178,748
Short-term borrowings	509,136	326,617
Long-term debt	628,953	340,447
Derivative instruments	30,209	25,002
Fair Value
Financial Assets
Cash and cash equivalents	1,362,126	510,267
Investment securities	3,536,029	2,901,247
Loans and loans held for sale, net of unearned income and allowance for loan losses	15,066,055	14,674,749
FDIC loss share receivables	0	9,163
Derivative instruments	38,886	30,486
Financial Liabilities
Deposits	16,762,475	15,696,245
Short-term borrowings	509,136	326,617
Long-term debt	617,656	309,847
Derivative instruments	$ 30,209	$ 25,002

Related Party Transactions (Det

Related Party Transactions (Details) $ in Thousands	Feb. 15, 2017USD ($)	Dec. 31, 2016USD ($)bank	Dec. 31, 2015USD ($)
Related Party Transaction [Line Items]
Total debt outstanding to all lenders		$ 628,953	$ 340,447
Affiliated Entity | Stone Energy Corporation | Credit Facility
Related Party Transaction [Line Items]
Number of banks party to facility | bank		12
Total debt outstanding to all lenders		$ 341,500
Borrowing base		$ 360,000
Affiliated Entity | Stone Energy Corporation | IBERIABANK | Credit Facility
Related Party Transaction [Line Items]
Percent of commitments held under facility		6.00%
Outstanding balance to IBERIABANK		$ 20,300
Subsequent Event | Affiliated Entity | Stone Energy Corporation | Exit Facility
Related Party Transaction [Line Items]
Debt Instrument term	4 years
Borrowing base	$ 200,000
Subsequent Event | Affiliated Entity | Stone Energy Corporation | IBERIABANK | Exit Facility
Related Party Transaction [Line Items]
Outstanding balance to IBERIABANK	$ 20,300

Business Segments (Detail)

Business Segments (Detail)	12 Months Ended
	Dec. 31, 2016Segment
Segment Reporting [Abstract]
Number of business segments	3

Business Segments - Schedule of

Business Segments - Schedule of Segment Reporting Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information
Interest and dividend income	$ 716,939	$ 646,858	$ 504,815
Interest expense	67,701	59,100	44,704
Net interest income	649,238	587,758	460,111
Provision for loan losses	44,424	30,908	19,060
Mortgage income	83,853	80,662	51,797
Title revenue	22,213	22,837	20,492
Other non-interest income	127,755	116,894	101,339
Allocated expenses	0	0	0
Non-interest expense	566,665	570,305	473,614
Income before income tax expense	271,970	206,938	141,065
Income tax expense	85,193	64,094	35,683
Net income	186,777	142,844	105,382
Total loans and loans held for sale, net of unearned income	15,222,012	14,493,675	11,581,116
Total assets	21,659,190	19,504,068	15,757,904
Total deposits	17,408,283	16,178,748	12,520,525
Average assets	20,321,234	18,402,706	14,631,994
Operating Segments | IBERIABANK
Segment Reporting Information
Interest and dividend income	707,676	639,793	498,820
Interest expense	64,068	56,222	42,983
Net interest income	643,608	583,571	455,837
Provision for loan losses	44,336	30,908	18,966
Mortgage income	405	966	71
Title revenue	0	0	0
Other non-interest income	127,751	116,903	101,401
Allocated expenses	(13,972)	(16,253)	(11,602)
Non-interest expense	484,099	495,158	412,165
Income before income tax expense	257,301	191,627	137,780
Income tax expense	79,565	58,006	34,352
Net income	177,736	133,621	103,428
Total loans and loans held for sale, net of unearned income	15,004,360	14,305,663	11,415,973
Total assets	21,319,267	19,220,085	15,537,731
Total deposits	17,402,742	16,173,831	12,515,329
Average assets	19,959,261	18,146,216	14,430,768
Operating Segments | IMC
Segment Reporting Information
Interest and dividend income	9,261	7,062	5,992
Interest expense	3,633	2,878	1,721
Net interest income	5,628	4,184	4,271
Provision for loan losses	88	0	94
Mortgage income	83,448	79,696	51,726
Title revenue	0	0	0
Other non-interest income	4	(2)	(61)
Allocated expenses	10,686	12,036	8,203
Non-interest expense	65,133	57,784	44,761
Income before income tax expense	13,173	14,058	2,878
Income tax expense	5,023	5,581	1,148
Net income	8,150	8,477	1,730
Total loans and loans held for sale, net of unearned income	217,652	188,012	165,143
Total assets	315,057	256,888	194,156
Total deposits	5,541	4,917	5,196
Average assets	335,913	230,819	176,003
Operating Segments | LTC
Segment Reporting Information
Interest and dividend income	2	3	3
Interest expense	0	0	0
Net interest income	2	3	3
Provision for loan losses	0	0	0
Mortgage income	0	0	0
Title revenue	22,213	22,837	20,492
Other non-interest income	0	(7)	(1)
Allocated expenses	3,286	4,217	3,399
Non-interest expense	17,433	17,363	16,688
Income before income tax expense	1,496	1,253	407
Income tax expense	605	507	183
Net income	891	746	224
Total loans and loans held for sale, net of unearned income	0	0	0
Total assets	24,866	27,095	26,017
Total deposits	0	0	0
Average assets	$ 26,060	$ 25,671	$ 25,223

Condensed Parent Company Onl126

Condensed Parent Company Only Financial Statements - Condensed Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assets
Cash in bank	$ 295,896	$ 241,650
Other assets	651,229	650,907
Total Assets	21,659,190	19,504,068	$ 15,757,904
Liabilities and Shareholders’ Equity
Liabilities	18,719,496	17,005,233
Shareholders’ equity	2,939,694	2,498,835	$ 1,852,148	$ 1,530,346
Total Liabilities and Shareholders’ Equity	21,659,190	19,504,068
IBERIABANK Corporation
Assets
Cash in bank	436,792	154,298
Investments in subsidiaries	2,635,682	2,449,325
Other assets	40,423	54,454
Total Assets	3,112,897	2,658,077
Liabilities and Shareholders’ Equity
Liabilities	173,203	159,242
Shareholders’ equity	2,939,694	2,498,835
Total Liabilities and Shareholders’ Equity	$ 3,112,897	$ 2,658,077

Condensed Parent Company Onl127

Condensed Parent Company Only Financial Statements - Condensed Statements of Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating income
Other income	$ 34,629	$ 26,510	$ 18,998
Operating expenses
Interest expense	67,701	59,100	44,704
Salaries and employee benefits expense	331,686	322,586	259,086
Other expenses	45,737	52,856	47,913
Income (loss) before income tax benefit and increase in equity in undistributed earnings of subsidiaries	271,970	206,938	141,065
Income tax benefit	85,193	64,094	35,683
Net Income	186,777	142,844	105,382
Preferred stock dividends	(7,977)	0	0
Net Income Available to Common Shareholders	178,800	142,844	105,382
IBERIABANK Corporation
Operating income
Reimbursement of management expenses	65,104	59,255	46,433
Other income	829	(329)	437
Total operating income	65,933	58,926	46,870
Operating expenses
Interest expense	3,948	3,393	3,224
Salaries and employee benefits expense	45,623	41,689	31,981
Other expenses	19,566	17,492	14,576
Total operating expenses	69,137	62,574	49,781
Income (loss) before income tax benefit and increase in equity in undistributed earnings of subsidiaries	(3,204)	(3,648)	(2,911)
Income tax benefit	530	800	(518)
Income (loss) before equity in undistributed earnings of subsidiaries	(3,734)	(4,448)	(2,393)
Equity in undistributed earnings of subsidiaries	190,511	147,292	107,775
Net Income	186,777	142,844	105,382
Preferred stock dividends	(7,977)	0	0
Net Income Available to Common Shareholders	$ 178,800	$ 142,844	$ 105,382

Condensed Parent Company Onl128

Condensed Parent Company Only Financial Statements - Condensed Statements of Cash Flows (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash Flow from Operating Activities
Net income	$ 186,777	$ 142,844	$ 105,382
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	5,332	15,457	15,791
Gain on sale of assets	(58)	(2,539)	(14)
Tax benefit associated with share-based payment arrangements	(1,122)	(580)	(2,105)
Other operating activities, net	64,460	26,798	(10,354)
Net Cash Provided by Operating Activities	306,966	196,123	119,363
Cash Flow from Investing Activities
Cash paid in excess of cash received for acquisitions	0	425,581	188,803
Proceeds from sale of premises and equipment	1,941	13,309	5,129
Purchases of premises and equipment, net of premises and equipment acquired	(12,840)	(19,502)	(29,841)
Other investing activities, net	3,450	30,134	19,950
Net Cash Used in Investing Activities	(1,424,397)	(570,972)	(712,755)
Cash Flow from Financing Activities
Cash dividends paid on common stock	(56,793)	(52,318)	(43,070)
Cash dividends paid on preferred stock	(7,028)	0	0
Net share-based compensation stock transactions	6,899	1,915	7,966
Payments to repurchase common stock	(11,666)	0	0
Net proceeds from issuance of common stock	279,242	0	0
Net proceeds from issuance of preferred stock	55,285	76,812	0
Tax benefit associated with share-based payment arrangements	1,122	580	2,105
Net Cash Provided by Financing Activities	1,969,290	337,021	750,091
Net Increase (Decrease) In Cash and Cash Equivalents	851,859	(37,828)	156,699
Cash and Cash Equivalents at Beginning of Period	510,267	548,095	391,396
Cash and Cash Equivalents at End of Period	1,362,126	510,267	548,095
IBERIABANK Corporation
Cash Flow from Operating Activities
Net income	186,777	142,844	105,382
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	98	416	595
Net income of subsidiaries	(190,511)	(147,292)	(107,775)
Share-based compensation cost	14,523	13,906	11,985
Gain on sale of assets	0	(110)	0
Tax benefit associated with share-based payment arrangements	(1,122)	(580)	(2,105)
Other operating activities, net	12,417	82,105	(27,274)
Net Cash Provided by Operating Activities	22,182	91,289	(19,192)
Cash Flow from Investing Activities
Cash paid in excess of cash received for acquisitions	0	(5,054)	4,783
Proceeds from sale of premises and equipment	0	12	0
Purchases of premises and equipment, net of premises and equipment acquired	0	(2)	(36)
Return of capital from (Capital contributed to) subsidiary	(6,000)	5,000	(14,600)
Other investing activities, net	(749)	0	0
Net Cash Used in Investing Activities	(6,749)	(44)	(9,853)
Cash Flow from Financing Activities
Cash dividends paid on common stock	(56,793)	(52,318)	(43,070)
Cash dividends paid on preferred stock	(7,028)	0	0
Net share-based compensation stock transactions	6,899	1,915	7,966
Payments to repurchase common stock	(11,666)	0	0
Net proceeds from issuance of common stock	279,242	0	0
Net proceeds from issuance of preferred stock	55,285	76,812	0
Tax benefit associated with share-based payment arrangements	1,122	580	2,105
Net Cash Provided by Financing Activities	267,061	26,989	(32,999)
Net Increase (Decrease) In Cash and Cash Equivalents	282,494	118,234	(62,044)
Cash and Cash Equivalents at Beginning of Period	154,298	36,064	98,108
Cash and Cash Equivalents at End of Period	$ 436,792	$ 154,298	$ 36,064