Entity information:
Income Taxes
Income tax expense consisted of the following:
 
Years Ended December 31,
 
2017
 
2016
 
2015
 
(In Thousands)
Current income tax expense:
 
 
 
 
 
Federal
$
158,531

 
$
154,572

 
$
275,135

State
19,588

 
13,322

 
12,409

Total
178,119

 
167,894

 
287,544

Deferred income tax expense (benefit):
 
 
 
 
 
Federal
141,093

 
(19,973
)
 
(102,070
)
State
(3,136
)
 
(1,900
)
 
(8,972
)
Total
137,957

 
(21,873
)
 
(111,042
)
Total income tax expense
$
316,076

 
$
146,021

 
$
176,502


Income tax expense differed from the amount computed by applying the federal statutory income tax rate to pretax earnings for the following reasons:
 
Years Ended December 31,
 
2017
 
2016
 
2015
 
Amount
 
Percent of Pretax Earnings
 
Amount
 
Percent of Pretax Earnings
 
Amount
 
Percent of Pretax Earnings
 
(Dollars in Thousands)
Income tax expense at federal statutory rate
$
271,902

 
35.0
 %
 
$
181,140

 
35.0
 %
 
$
239,351

 
35.0
 %
Increase (decrease) resulting from:
 
 
 
 
 
 
 
 
 
 
 
Goodwill impairment

 

 
20,965

 
4.0

 
5,950

 
0.9

Tax-exempt interest income
(56,814
)
 
(7.3
)
 
(51,246
)
 
(9.9
)
 
(49,170
)
 
(7.2
)
Change in valuation allowance
(1,167
)
 
(0.2
)
 
402

 
0.1

 
(2,029
)
 
(0.3
)
Bank owned life insurance
(5,988
)
 
(0.8
)
 
(6,035
)
 
(1.2
)
 
(6,082
)
 
(0.9
)
Income tax credits
(25,635
)
 
(3.3
)
 
(11,257
)
 
(2.2
)
 
(10,238
)
 
(1.5
)
State income tax, net of federal income taxes
14,118

 
1.8

 
7,106

 
1.4

 
4,154

 
0.6

Revaluation of net deferred tax assets (1)
121,244

 
15.7

 

 

 

 

Other
(1,584
)
 
(0.2
)
 
4,946

 
1.0

 
(5,434
)
 
(0.8
)
Income tax expense
$
316,076

 
40.7
 %
 
$
146,021

 
28.2
 %
 
$
176,502

 
25.8
 %

(1) Includes approximately $40 million of expense related to items in accumulated other comprehensive income in which the related tax effects were originally recognized in other comprehensive income.
On December 22, 2017, President Trump signed the Tax Cuts and Jobs Act into legislation, which reduces the corporate tax rate from 35% to 21% effective January 1, 2018. ASC Topic 740, Income Taxes, requires the effect of a change in tax laws or rates to be recognized as of the date of enactment. The Company has recorded tax expense of $121.2 million, primarily due to the remeasurement of deferred tax assets and liabilities at the federal tax rate of 21%. At December 31, 2017, the Company has recorded the effects of the change in tax law for the deferred tax assets and tax liabilities for which the accounting is complete and reported provisional amounts for the effects of the tax law changes for the deferred tax assets and liabilities for which the accounting is not complete, but for which a reasonable estimate can be determined. The Company may have to adjust the provisional amounts when it obtains, prepares or analyzes additional information about facts and circumstances that existed at the enactment date when the Company files its federal tax return for the tax year 2018 but no later than the measurement period of one year.
The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are presented below.
 
December 31,
 
2017
 
2016
 
(In Thousands)
Deferred tax assets:
 
 
 
Allowance for loan losses
$
197,563

 
$
309,655

Accrued expenses
89,847

 
121,459

Loan valuation

 
48,880

Net unrealized losses on investment securities available for sale, hedging instruments and defined benefit plan adjustment
73,424

 
98,916

Other real estate owned
467

 
567

Nonaccrual interest
17,737

 
22,707

Federal net operating loss carryforwards
6,906

 
15,041

Other
35,416

 
57,216

Gross deferred taxes
421,360

 
674,441

Valuation allowance
(11,641
)
 
(14,639
)
Total deferred tax assets
409,719

 
659,802

Deferred tax liabilities:
 
 
 
Premises and equipment
147,542

 
243,113

Core deposit and other acquired intangibles
6,864

 
13,117

Capitalized loan costs
32,584

 
47,527

Loan valuation
1,648

 

Other
12,832

 
24,309

Total deferred tax liabilities
201,470

 
328,066

Net deferred tax asset
$
208,249

 
$
331,736

As of December 31, 2017 and 2016, the Company has approximately $14.1 million and $24.1 million of federal net operating loss carryforwards for future utilization, primarily attributable to Simple in 2017 and 2016. These losses begin to expire in 2034. The Company believes that it is more likely than not that the benefit from these deferred tax assets will be realized.
A real estate investment subsidiary of the Company has net operating loss carryforwards of approximately $18.8 million at both December 31, 2017 and 2016. These losses begin to expire in 2030.  The Company has determined that it is more likely than not the benefit from this deferred tax asset will not be realized in the carryforward period and has recorded a full valuation allowance of approximately $4.0 million and $6.6 million against the assets at December 31, 2017 and 2016, respectively.
Additionally, the Company has state net operating loss carryforwards of approximately $231.0 million and $238.0 million at December 31, 2017 and 2016, respectively.  These state net operating losses expire in years 2018 through 2034.  The Company believes it is more likely than not the benefit from certain state net operating loss carryforwards will not be realized, and, accordingly, has established a valuation allowance associated with these net operating loss carryforwards.  The Company had recorded a valuation allowance of approximately $7.7 million and $8.0 million at December 31, 2017 and 2016, respectively, related to these state net operating loss carryforwards.
The following is a tabular reconciliation of the total amounts of the gross unrecognized tax benefits.
 
Years Ended December 31,
 
2017
 
2016
 
2015
 
(In Thousands)
Unrecognized income tax benefits, at beginning of year
$
13,615

 
$
16,552

 
$
28,286

Increases for tax positions related to:
 
 
 
 
 
Prior years
414

 

 
58

Current year
2,196

 
1,933

 
1,537

Decreases for tax positions related to:
 
 
 
 
 
Prior years

 
(2,185
)
 
(85
)
Current year

 

 

Settlement with taxing authorities

 
(1,174
)
 
(583
)
Expiration of applicable statutes of limitation
(1,309
)
 
(1,511
)
 
(12,661
)
Unrecognized income tax benefits, at end of year
$
14,916

 
$
13,615

 
$
16,552


During the years ended December 31, 2017, 2016 and 2015, the Company recognized benefits of $(872) thousand, $(1.8) million and $(3.2) million, respectively, for interest and penalties related to the unrecognized tax benefits noted above. At December 31, 2017 and 2016, the Company had approximately $4.3 million and $5.1 million, respectively, of accrued interest and penalties recognized related to unrecognized tax benefits within accrued expenses and other liabilities. Included in the balance of unrecognized tax benefits at December 31, 2017, 2016 and 2015 were $14.9 million, $13.6 million and $16.6 million, respectively, of tax benefits that, if recognized after the balance sheet date, would affect the effective tax rate.
The Company and its subsidiaries are routinely examined by various taxing authorities. The following table summarizes the tax years that are either currently under examination or remain open under the statute of limitations and subject to examination by the major tax jurisdictions in which the Company operates:
Jurisdictions
 
Open Tax Years
Federal
 
2014-2017
Various states (1)
 
2006-2017
(1)Major state tax jurisdictions include Alabama, California, Texas and New York.
The Company believes that it has adequately reserved on federal and state issues and any variance on final resolution, whether over or under the reserve amount, would be immaterial to the financial statements.
It is reasonably possible that the above unrecognized tax benefits could be reduced by approximately $7 million in 2018 due to statute expiration and audit settlement.